Our HAP and lung health in women study enrolled 790 women in rural and urban households in Zimbabwe between March 2018 and December 2019. Here, we report data from 148 rural households using solid fuel as the primary source of fuel for cooking and heating and where indoor air samples were collected. Data on kitchen characteristics and practices were collected cross-sectionally using an indoor walk-through survey and a modified interviewer-administered questionnaire. An Air metrics miniVol Sampler was utilized to collect PM2.5 samples from the 148 kitchens over a 24 h period. To identify the kitchen features and practices that would likely influence PM2.5 concentration levels, we applied a multiple linear regression model. The measured PM2.5 ranged from 1.35 μg/m3 to 1940 μg/m3 (IQR: 52.1–472). The PM2.5 concentration levels in traditional kitchens significantly varied from the townhouse type kitchens, with the median for each kitchen being 291.7 μg/m3 (IQR: 97.2–472.2) and 1.35 μg/m3 (IQR: 1.3–97.2), respectively. The use of wood mixed with other forms of biomass was found to have a statistically significant association (p < 0.001) with increased levels of PM2.5 concentration. In addition, cooking indoors was strongly associated with higher PM2.5 concentrations (p = 0.012). Presence of smoke deposits on walls and roofs of the kitchens was significantly associated with increased PM2.5 concentration levels (p = 0.044). The study found that kitchen type, energy type, cooking place, and smoke deposits were significant predictors of increased PM2.5 concentrations in the rural households. Concentrations of PM2.5 were high as compared to WHO recommended exposure limits for PM2.5. Our findings highlight the importance of addressing kitchen characteristics and practices associated with elevated PM2.5 concentrations in settings where resources are limited and switching to cleaner fuels may not be an immediate feasible option.Household air pollution (HAP) from biomass fuels significantly contributes to cardio-respiratory morbidity and premature mortality globally. Particulate matter (PM), one of the pollutants generated, remains the most accurate indicator of household air pollution. Determining indoor air concentration levels and factors influencing these levels at the household level is of prime importance, as it objectively guides efforts to reduce household air pollution. This paper describes household factors associated with increased PM An estimated 2.6 billion people worldwide are at risk of ill health and premature deaths annually due to household air pollution (HAP) from domestic use of biomass fuel   is an important metric to estimate the risk of respiratory illness since these very small particles have the capacity to penetrate deep into the lungs when inhaled [3 24 h mean for PM2.5 [Inefficient burning cookstoves used with biomass fuels generate a wide range of air pollutants , includi inhaled . The Woror PM2.5 .2.5 concentration levels in diverse environments [2.5 concentrations, whilst the presence of a chimney did not [2.5 and concluded that stove type, heating fuel, and presence of a chimney partially explained the variation of PM2.5 kitchen concentrations [2.5 concentrations [Indoor concentrations of pollutants are affected by several household-level factors , which mronments ,17,18. P did not . Shuplertrations . In all trations . Anothertrations . In theitrations . From th2.5, it is necessary to understand a number of factors at the household level [2.5 concentration levels in rural Zimbabwean households.In Zimbabwe, about 67.7% of people live in rural regions , and mosld level , includi2.5 in 148 of the 790 households recruited for the Biomass smoke and lung health in adult women in Zimbabwean families study.In the rural district of Goromonzi in the Mashonaland East province of Zimbabwe, a community-based, cross-sectional study was conducted among women aged 18 years and older who use biomass as their primary source of fuel. We evaluated the 24 h kitchen area concentrations of PMn = 466 out of the 790 households in the parent study) were using biomass as their primary source of fuel. However, for this paper, we selected only those households (n = 148) where indoor air samples had been collected , construction material used , as well as evidence of exposure to biomass smoke . Kitchen types were categorized into traditional (thatched kitchens) and townhouse (brick under asbestos/tile/corrugated iron kitchens), while cooking areas were categorized as separate kitchen indoors and hut/detached building and outdoors. We further categorized stoves as traditional solid fuel stoves and improved solid fuel stoves. For this study, a traditional solid fuel stove is one with an open fire and no smoke exhaust. An improved solid fuel stove is one that has an exhaust, such as a chimney or a hole in the side of the stove, which channels smoke outside of the room. 2.5) over a 24 h period continuously using a calibrated battery-operated Air Metrics Minivol model TAS 5.0 portable air sampler equipped with a 47 mm PTFE (Teflon/polytetrafluoroethylene) filter with 2.0 μm pore size [2.5, and we analyzed gravimetrically as part of quality control. We recorded activities done during the sampling period at the end of the sampling time to determine any other possible sources of PM2.5 during the sampling period.The primary use of solid fuel for cooking was used as an indicator of HAP exposure among rural participants. We measured the indoor (kitchen area) concentration of airborne particulate matter with an aerodynamic diameter < 2.5 µm ;M2 = filter mass after sampling (mg);MB = average mass change of blanks (mg);S = volume of air sampled (m3) [Vled (m3) .Weighing of filters was done using a micrometric balance  with accuracy of 0.001 mg in a laboratory with controlled humidity of 36% to 41% and temperature of 18–23 °C. Prior to the pre-sampling and post-sampling weighing sessions, all filters were equilibrated for 24 h. The filters were pre-weighed until the 0.01st milligram was stable according to the American Society for Testing and Materials (ASTM) D 1739. Filters were then stored in filter cassettes in a box and transported to the field at room temperature. The flow rate of the sampler was calibrated during deployment, and at the conclusion of the sampling time, the flow rate was once more measured using a rotameter. The change in mass at the end of the sampling period minus the blank mass change was simply divided by the volume of air sampled, and a concentration level was produced, as indicated in Equation (1). The measured PM3) throughout the course of a 24 h period. The ultimate mass concentration was estimated in mg/m3. The limit of detection (LOD) of the weighing procedure was determined from three times the standard deviation of the weight changes of field blank filters [3 [3.It was calculated using the typical sample flow rate, the sampling duration, and the surrounding pressure and temperature. As a result, each household had its air tested for about 7200 L .Samples from 148 kitchens that used biomass as their primary source of fuel were analyzed for this work. The median PM2.5 concentration between traditional kitchens and townhouse-type kitchens, with median concentration levels being 291.7 μg/m3 (IQR = 97.2–472.2 μg/m3) and 1.35 μg/m3 (IQR = 1.3–97.2 μg/m3), respectively (p = 0.008). In addition, it was observed that kitchens that had mud walls had increased PM2.5 concentration levels compared to kitchens that had walls made of tile, asbestos, or corrugated iron (p = 0.134). However, this discrepancy did not reach statistical significance. A limited number of kitchens (22.3%) included in the study were found to have chimneys. These kitchens exhibited elevated levels of PM2.5 concentration in comparison to those without chimneys (p = 0.102). However, the observed difference was not statistically significant. The study findings indicate that a minority of the participants (38.4%) reported preparing meals more than three times a day, and their kitchens had lower PM2.5 concentration levels compared to those who prepared less than three meals per day, but the observed difference was not statistically significant (p = 0.100).p = 0.286), roof type (p = 0.618), floor type (p = 0.944), having ever stayed with a smoker (p = 0.656), biomass use duration (p = 0.898), time spent cooking per day (p = 0.902), window opening frequency (p = 0.944), and monthly income (p = 0.966) had no statistically significant associations with the PM2.5 concentration levels in the sampled households  compared to 263.9 μg/m3 (IQR (1.3–97.2) in the kitchens of those who did not report it. The most used type of stove in this study was the traditional solid fuel stove (87.8%), and its use was significantly associated with increased PM2.5 concentration levels as compared to the improved solid fuel stove (p = 0.072). Most of the participants in this study (87.8%) used wood in combination with other biomass fuels to enhance the fire during cooking times. Comparing use of wood only and use of wood mixed with other types of biomass fuels such as cow dung and crop residues, using wood only was associated with decreased PM2.5 concentration levels (p = 0.001). Most participants (70.3%) reported cooking inside the hut, while the rest of the respondents reported that they cooked outdoors or in other separate rooms. Cooking indoors was significantly associated with increased PM2.5 concentration levels, with the median being 333.3 μg/m3 compared to 118.1 μg/m3 among those who did not cook indoors. More than half (53.4%) of the kitchens that were sampled had heavy smoke deposits on the walls and roof. These kitchens were significantly associated with increased PM2.5 levels (p = 0.018) as compared to the kitchen that had none to modest smoke deposits.Evidence of tobacco smoking was reported by few participants (4.7%); however, it was significantly associated with an increase in PMp = 0.786), incense use (p = 0.263), and use of a space heater (p = 0.632) had no significant association with PM2.5 levels in the sampled households  between the traditional kitchen type and elevated levels of PM2.5 in comparison to the townhouse kitchen type. The study also found a significant correlation between increased levels of PM2.5 concentration and the energy type, cooking in a hut, and heavy smoke deposits. In addition, the use of wood in combination with other forms of biomass such as cow dung and crop residue were found to be correlated with heightened levels of PM2.5. 2.5 concentration levels. Preparing meals more than three times was found to have a statistically significant correlation with low PM2.5 concentration levels (p = 0.054). Compared to households that had none to modest smoke deposits on the kitchen roofs and windows, heavy smoke deposits in the kitchen were associated with increased PM2.5 concentration levels, and the difference was statistically significant (p = 0.043). There was a positive correlation between households that had evidence of tobacco smoking and elevated levels of PM2.5 (p = 0.056), but it was not statistically significant. Having a chimney (p = 0.622) and cement/wood/corrugated iron wall type (p = 0.251) were not associated with the PM2.5 concentration levels.Contrary to the univariate analysis findings, use of traditional solid fuel stoves was associated with decreased PM2.5 concentration levels as determined by the stepwise multiple linear regression model. The statistical model exhibited a superior fit, as evidenced by a significant overall goodness-of-fit  and an adjusted R2 value of 0.355. The findings of the study indicate a statistically significant association between traditional kitchens and elevated levels of PM2.5 as compared to townhouse kitchens (p = 0.033). Statistically significant correlations were also noted between elevated levels of PM2.5 concentration levels and energy type (p = 0.001), cooking in a hut (p = 0.001), and heavy smoke deposits (p = 0.044). Furthermore, the use of wood in conjunction with other types of biomass such as cow dung and crop residue was associated with increased PM2.5 concentration (p = 0.001) compared to the use of wood only. 2.5 (p = 0.056), the relationship was not statistically significant. Even though use of traditional solid fuel stove was initially found to be associated with increased PM2.5, it became significantly associated with reduced PM2.5 concentration levels after the multivariate analysis (p = 0.006). Comparing the number of meals prepared per day, those who prepared more than three meals per day had decreased PM2.5 concentration levels compared to those who prepared less than three meals per day; however, the difference was not statistically significant (p = 0.056).Whilst there was a positive correlation between households with evidence of tobacco smoking and elevated levels of PM2.5 concentration levels in Zimbabwean rural households are high, with most of them having levels above the WHO-recommended exposure limits for PM2.5. This is congruent with previous studies done in Zimbabwe, where levels of >40 μg/m3 have been reported [2.5 concentration after stepwise regression model were kitchen type, energy type, cooking place, and smoke deposits. Our study showed that PMreported ,37,38, areported ,18,23,392.5 [2.5 concentration levels in the univariate analysis. The energy ladder depicts socioeconomic status as an important determinant of fuel preferences at the household level [Consistent with previous studies, traditional type of kitchens had significantly higher levels of PM2.5 . These k2.5 . It is ald level ,41,42. 2.5 exposure among people who used biomass as the primary source of fuel [Additionally, income influences other factors such as kitchen characteristics, stove type, and food preparation frequency. Fandiño-Del-Rio et al. (2020) also reported that higher kitchen PM concentrations were likewise related to lower levels of wealth in Peru . The ass of fuel .2.5 concentration levels compared to those households that use the improved solid fuel stoves. This finding is opposed to what Clark et al. (2016) found, where improved cooking stoves were associated with reduced indoor air concentration levels [2.5 concentrations associated with each type [2.5 were lower in improved solid fuel stoves than in traditional solid fuel stoves [A significant percentage of the study participants (88.4%) indicated that they used traditional solid fuel stoves. Contrary to what other studies have found, these households exhibited lower PMn levels . Howeverach type . Yip et l stoves . 2.5 concentration levels. This could be because the other types of biomass are regarded as the least-efficient burning types of biomass fuels on the energy ladder [When compared to the use of wood alone, the use of wood combined with other types of biomass such as cow dung and crop residues resulted in a significant increase in PMy ladder . Researcy ladder . It is t2.5 concentrations in kitchens where cooking occurred inside. When cooking is done inside, the released smoke remains suspended in the atmosphere for prolonged periods of time mainly due to poor ventilation, exposing residents to home air pollution. The element of cooking inside is connected to kitchen type since it determines whether or not indoor air pollutants will accumulate; it all relies on the type of the kitchen.It is well known that using biomass fuels indoors for cooking causes HAP, especially when the area is not well ventilated. Throughout this study, we detected higher PM2.5 concentration levels are linked to the presence of smoke deposits in the kitchen or cooking area. Previous studies have highlighted how certain contaminants are deposited on kitchen walls before leaving the kitchens [In this investigation, there were smoke deposits in around 53.4% of the kitchens, and this was statistically significant. It is widely known that higher PMkitchens . This phkitchens ,46.2.5 concentration levels compared to those who prepared less than three meals per day. It may be difficult to use this variable as a proxy for indoor PM2.5 concentration levels unless there are more details about the types of meals that were prepared and the duration it took to prepare each meal. There are many contextual differences in the way that meals are prepared in one household or another. Therefore, it is difficult to interpret the association between the measured PM2.5 concentration levels and the number of prepared meals per day. A person may report making one or two meals per day but may spend more time doing so than someone who prepares more than three meals per day.Approximately 38.4% of the study participants reported that they prepared more than three meals per day, and their kitchens recorded lower PM2.5 concentrations in rural areas, as in the case of our context, are unlikely to significantly contribute to the exposures experienced by individuals who cook with biomass [2.5 was the most significant predictor for indoor concentration levels [While previous studies have demonstrated that monitoring both indoor and outdoor air sampling is necessary for characterizing HAP, such monitoring was not possible in this investigation due limited resources and logistical constraints. However, some studies have argued that the background ambient PM biomass , while t biomass . In a din levels  such than levels . The majn levels .However, there are important strengths in our study; for instance, we used the gravimetric sampling technique, which is considered the gold standard in air sampling because it is precise and accurate. Furthermore, we were able to collect detailed data from the households and carried out indoor walk-through assessments to aid with gathering adequate information about the households.2.5, the PM2.5 concentrations in this study were excessive. Significant predictors of PM2.5 concentrations included kitchen type, energy type, cooking place, and smoke deposits. Our findings underscore the need to educate the public on the impact of HAP exposure and the best practices for minimizing exposure in the home as a means of lowering pollution levels. A coordinated effort including all stakeholders might produce encouraging outcomes. An acceptable strategy would include a nationwide public awareness campaign on the link between indoor air pollution and poor health and practical action. It is important to look at how the traditional kitchens are designed and aim to improve kitchen design to reduce indoor accumulation of smoke. There is a need to instill behavior change among the at-risk population by adopting low-cost methods to prevent HAP. Policymakers can also play a role by enacting measures to ensure that kitchens are built to a certain standard using materials that may not promote accumulation of pollutants indoors. To reduce the indoor PM2.5 levels in rural kitchens in Zimbabwe, alterations to the kitchen’s physical characteristics to ensure that it allows air exchange during cooking times may be of benefit. When compared to the WHO-recommended exposure limits for PM


A. baumannii, has become a globally challenge. The increasing hospital outbreaks by multi-drug resistant (MDR) A. baumannii strains, shows the necessity of continuous monitoring to find sources of resistant strains in hospitals. This study aimed to identify the presence of class 1 integrons and metallo-β-lactamase (MBL) related genes in A. baumannii isolates from hospital environment.The emergence and widespread dissemination of antibiotic resistance in A. baumannii isolates, a total of 297 environmental samples were collected from burn wards and intensive care units (ICUs) of two university hospitals. Resistance to common antibiotics was studied by disk diffusion method and microbroth dilution assay was used to determine the minimum inhibitory concentrations (MICs) of imipenem, colistin and tigecycline. The A. baumannii isolates were studied by polymerase chain reaction (PCR) for the presence of class 1 integrons  and metallo-β-lactamases (MBLs)  genes.In order to identify A. baumannii was identified in 68/297 (22.9%) of hospital environment. All A. baumannii strains were multidrug-resistant (MDR), but none of them were resistant to colistin, tigecycline and ampicillin-sulbactam. All (100%) and 38 (95.0%) of A. baumannii isolates from ICUs and burn wards were imipenem resistant respectively. Class 1 integrons was identified in 30/40 (75.0%) and 23/28 (82.1%) isolates from burn wards and ICUs respectively. Two different types of gene cassettes were identified, which included: arr-2, ereC, aadA1, cmlA5 and arr2, cmlA5. MBL genes including blaVIM and blaIMP were detected in 26/28 (92.8%), 27/28(96.4%) and 39/40 (97.5%) and 31/40 (77.5%) of the isolates from the ICUs and the burn wards respectively. None of the isolates contained the blaNDM−1 gene.A. baumannii (CRAB) was relatively high in the environmental surface of burn wards and ICUs, which can be considered as a potential source of outbreaks in hospitalized patients.The findings of the present study showed that the isolation rate of MBL producing carbapenem-resistant  Acinetobacter baumannii (CRAB) is considered as a dangerous hospital pathogen  between April and September 2021. For sample collection moistened sterile cotton swabs were used, which was rolled over the surfaces. The collected environmental swabs were individually transferred to Brain Heart Infusion broth  media and incubated overnight at 37oC. Then the swabs were cultured on MacConkey agar and blood agar  plates at 37oC for 24 h. A. baumannii isolates were identified by standard biochemical tests and confirmed using PCR amplification of the rpoB, blaOXA-51 and gluconolactonase genes [A total of 297 environmental samples, were collected from burn wards and ICUs of two university hospitals [Shahid Motahari Hospital  [A. baumannii isolate was defined as MDR if it was resistant to three or more antimicrobial classes.Resistance patterns of e (CLSI) , using ae (CLSI) . The A. Escherichia coli ATCC 25,922 and Pseudomonas aeruginosa ATCC 27,853, were obtained from Pasteur Institute of Iran, used as the quality control strains.The minimum inhibitory concentrations (MICs) of imipenem, colistin and tigecycline were determined by microbroth dilution method. Susceptibility interpretation was done according to antimicrobial breakpoints organized by CLSI and European Committee on Antimicrobial Susceptibility Testing (EUCAST) . FurtherintI1, intl CS) and MBLs genes  was assessed by PCR using specific primers , 40 cycles of , followed with 5 min at 72ºC. The amplification programs of the blaVIM, and blaIMP genes were as follows: one cycle of 95 °C for 5 min; 35 cycles of 95 °C for 45 s; 55 °C for 45 s and 72 °C for 1 min, ending with a final extension temperature of 72ºC for 10 min [blaNDM− 1 gene were programmed as follows: initial denaturation at 94 °C for 10 min, 36 cycles of denaturation , annealing  and primer extension , with a final extension at 72 °C for 10 min [A. baumannii strains carrying the studied genes, which were previously confirmed by sequencing, were used as positive controls.The presence of class 1 integrons genes . Comparison between variables was done using Chi-square or Fisher’s exact tests. A. baumannii isolates were identified in different environmental surface of Shahid Motahari Hospital in Tehran and 15/57 (26.3%) A. baumannii isolates from different environment of Shahid Madani Hospital in Karaj  % A. baumA. baumannii isolates from the hospital environment were MDR and showed resistance to three or more antimicrobial classes. In addition, none of the isolates were resistant to colistin, tigecycline and ampicillin-sulbactam. The highest level of resistance was obtained to trimethoprim/sulphamethoxazole and ceftazidime and 100% A. baumannii isolates from burn wards and ICUs were resistant to the mentioned antibiotics. In addition, resistance rates to imipenem in ICUs and burn wards were 100% and 95% respectively. All 28/28(100%), 33/40 (82.5%), 26/28(92.9%), 33/40 (82.5%) of A. baumannii isolates from ICUs and burn wards, were resistant to ciprofloxacin, and gentamicin respectively. The study of the resistance pattern also indicated that 4/28 (14.3%), 2/28 (7.1%) and 2/28 (7.1%) of A. baumannii isolates from ICUs were resistant to doxycycline, ampicillin-sulbactam and minocycline respectively, while none of the isolates from the burn wards were resistant to the mentioned antibiotics. Class 1 integrons integrase gene (intI1), was detected in 53/68 (77.9%) of A. baumannii isolates including 30/40 (75.0%) isolates from burn wards and 23/28 (82.1%) isolates from ICUs. All the intI1-positive A. baumannii strains were also positive for the intl CS gene  of intI1-positive A. baumannii strains. MBL genes including blaVIM and blaIMP were detected in 65/68 (95.6%) and 58/68 (85.3%) of A. baumannii isolates respectively, out of which 26/28 (92.8%) and 27/28(96.4%) % of the isolates from ICUs and 39/40 (97.5%) and 31/40 (77.5%) of the isolates from the burn wards contained blaVIM and blaIMP genes respectively  and 29/40 (72.5%) of isolates from the ICUs and the burn wards respectively (Table The results of resistance pattern investigation revealed all A. baumannii in the hospital environment leads to this bacterium facing selective pressure caused by antibiotics [A. baumannii strains in the hospital environment. MDR A. baumannii causes life-threatening infections with high mortality, especially in immunocompromised patients admitted to the ICUs [A. baumannii, which is somewhat higher compared to other similar studies [A. baumannii in the present study may be related to the mentioned factors or it may be due to the lack of accurate knowledge of the characteristics of this bacterium during the disinfection of the hospital environment. In a study investigating the persistence characteristics of A. baumannii, it was shown that after four rounds of manual disinfection with a bleach solution, 25% of the rooms were still contaminated with A. baumannii [A. baumannii isolates from burn wards and ICUs were MDR and the resistance rate to imipenem in ICUs was also 100%. In a study in Brazil, 80% of A. baumannii isolates from ICU environment and 80.4% of isolates from ICU patients at the same hospital were imipenem resistance [A. baumannii isolates from clinical and environmental samples in ICUs were MDR, and resistance to carbapenems has been reported with high frequency [A. baumannii were sensitive to colistin, and tigecycline. Since the environmental isolates of A. baumannii are considered as the source of outbreaks in hospitalized patients, the susceptibility of these strains to last resort antibiotics such as colistin and tigecycline is of great importance. In some studies, conducted in Iran, resistance to the above antibiotics has been reported among clinical resistant A. baumannii isolates from ICUs [A. baumannii isolates from the environment of the ICUs [A. baumannii and is usually carried out by carbapenemases, which are commonly associated with transmissible genetic elements such as integrons [A. baumannii [blaVIM and blaIMP genes were highly prevalent in the studied isolates although blaNDM−1 was not detected in the mentioned isolates. In agreement with our results, in study conducted by Amin et al. in Ahvaz in the southwest of Iran blaVIM has been reported as the most common MBL encoding gene followed by blaIMP, among clinical isolates of A. baumannii [A. baumannii isolates from burn wound infection, also indicated blaVIM was the most common MBL [A. baumannii isolates from the hospital wards and ICUs carried blaVIM gene, and the blaNDM−1 has been reported as the most common MBL gene in the mentioned isolates [blaNDM−1 has also been reported as the predominant MBL in A. baumannii strains isolated from neonatal sepsis in India [A. baumannii strains in various geographical regions and distinct clinical settings is different from each other. Various studies have identified integrons as one of the most important factors in the acquisition of antibiotic resistance genes in A. baumannii strains [A. baumannii strains [A. baumannii isolates, especially strains isolated from ICUs, carried class 1 integron. Compared to the results obtained in the study conducted in Africa on the A. baumannii isolates from the extra-hospital environment which lacked integrons class 1, this finding shows the very high potential of our studied strains to acquire and expand antibiotic resistance genes [The persistence of ibiotics . This fethe ICUs . Our stu studies , 26. The studies . The higaumannii . The stusistance . Consistrequency . Likewisrom ICUs . In addintegrons . MBLs anaumannii . Our premmon MBL . Althougisolates . The blain India . The fin strains . In part strains . In the ce genes .A. baumannii in the hospitals.The findings of the present study showed that the isolation rate of MBL producing CRAB was relatively high in the environmental surface of burn wards and ICUs, which can be considered as a potential source of outbreaks in hospitalized patients. Applying standard hospital infection prevention and control measures including hand hygiene, intense monitoring and better environmental disinfection can be the effective activities to prevent the outbreak of MDR A. baumannii strains isolated from clinical samples and comparison with environmental isolates in the studied hospitals.The most important limitation that can be expressed in this study is the lack of investigation of


CAR is one of the poorest countries in the world. While UN statistics suggest that there is no health emergency in the country, two recently published mortality surveys contradict this. Moreover, recent accusations of massive scale human rights abuses by mercenaries suggested the need for a nationwide mortality survey.Two stage cluster surveys were conducted in two different strata: one in the roughly half of the country within the Government’s control, and one in the areas mostly outside of the Government’s control. We randomly selected 40 clusters of 10 households in each stratum. The survey included questions on vital events with open-ended questions about health and household challenges at the beginning and end of each interview.70 of 80 selected clusters were successfully visited. We interviewed 699 households, containing 5070 people. 11 households (1.6%) refused to be interviewed and approximately 18.3% of households were absent at the time of visitation, mainly in the safer Government controlled areas. Interviewed households had a birth rate of 42.6 /1000 / year (95%CI 35.4–59.7) and a crude mortality rate (CMR) of 1.57 /10,000/day (95%CI: 1.36–1.78). The birth rate was lower and the death rate markedly higher in the strata outside of Government control. Families described malaria or fever, and diarrhea as the primary reported causes of death with violence accounting for 6% of all deaths.CAR is experiencing a severe health emergency, with the highest measured nationwide mortality in the world to our knowledge. UN published death rate estimates appear to be less than one fourth of reality. There is a desperate need for food aid in the form of general distributions in CAR, along with the accompanying work programs, seed and tool distributions needed to restart local economies. This is of particular importance in rural areas outside of the Government control. While some humanitarian actors are doing their best to respond, the crisis level mortality rate suggests that the needs in CAR are being largely unmet. The Central African Republic has a gross national income of $425 per person, a life expectancy of 54, and is ranked fourth from last on the Human Development Index , 2. For Following the publishing of 1992 Centers for Disease Control guidelines for public health emergencies, an acute health crisis has been widely accepted as occurring when the baseline mortality has either doubled or exceeded the rate of 1/10,000/day , 7. WhilTwo surveys published over the last two years have suggested that large areas of the country were experiencing mortality above the emergency threshold , 10. In To increase the precision of our mortality estimate, the national population was divided into two strata. The first, included the 52.5% of the population living in areas served and controlled by the national Government (GC). These included: the city of Bangui, and Ombella-M'Poko, Lobaye, Mambéré-Kadeï, Nana-Mambéré, Sangha-Mbaéré, Kémo Prefectures. The second strata included the remaining prefectures which were assessed by the national team members to be less stable, less supported by Governmental services, and partially out of the Government’s control , hereafter referred to as non-GC. This assessment of government control aligned with the assessment of a July 2021 map drawn by Political Geography Now .The survey sample size estimate was based on assumptions that: the baseline mortality was 1.0/1000/mo.  , each stThe survey was conducted in each stratum as a two-stage cluster design . In stagWe sought approval from Bangui and local administrative officials before visiting households in the clusters. We asked village or neighbourhood leaders if there had been any general population food distributions, and if there had been fighting between armed groups within 10 km of the village in 2022. We used GPS devices, phones, or in the riskiest areas, hand-drawn maps to identify the starting point of a cluster. Interviewers approached the 10 households nearest to the starting point. At each household, interviewers sought informed consent, by describing the purpose of the study, indicating there would be no direct rewards or benefits to participants and specifying that participation was completely voluntary. Interviewers sought verbal consent due to the low levels of literacy in most of CAR and the potential risk posed to interviewees if we sought written consent. If the interviewee agreed to participate, the interviewer signed a consent line on the data form.To be eligible for the study, the consenting individual needed to be 18 years of age and a resident in the visited household. A household was defined as a group of people who slept under the same roof or ate their meals together. Interviewers confirmed with respondents that household members had been present most of the last 30 nights. Those members who did not meet the criteria were excluded. No identifying information was collected on the data forms beyond household demographics. If a household refused to be interviewed, or was absent at the time of the visit, it was passed over and the next nearest household to the starting point was visited. We replaced empty households because past surveys found that rural villages had more empty households than urban and corrective weighting of clusters would have introduced bias. Because of logistical barriers, clusters were not revisited after the initial visit. In some areas, interviewers used local moto-taxis to access clusters as local drivers were less likely be attacked by armed groups. In such visits, no team leader was present and proper absentee data was not recorded, though refusal data was.The questionnaire consisted of 15 questions beginning with an open-ended question about the health challenges facing the household. This was followed by questions adopted from Medecins Sans Frontieres (MSF)’s mortality survey protocol on household demographics, pregnancies, births, deaths, household migration, and duration of residence. Finally, households were asked if they had received food in distributions of any kind in 2022. The survey concluded with an open-ended question asking if there was anything else they wanted to share. The inclusion of the open-ended questions provided households with an opportunity to raise concerns that may not have been anticipated in the pre-developed questionnaire. Interviews took approximately 15 min. We trained interviewers on the survey methods, the informed consent process, and all segments of the questionnaire, including household responses to open ended questions. The questionnaire was translated and back translated from French to Sango. Interviewers conducted the interviews in whatever language provided the best communication with respondents.Interviewers recorded answers on paper forms that were quality checked by team leaders in the field. Data was entered using Kobo Toolbox  and 10% The study was funded by an anonymous donor who had no communication with the team about study design, fieldwork undertaken, or results. IRB approval was obtained from The Comite National D’ethique de la Sante of the DRC Ministry of Health, CNES 001/DPSK/195PM/2022.We collected data from 70 of the 80 selected clusters, covering 14 of 17 prefectures. Seven clusters were missed because of security concerns (n = 6 in non-GC areas) and three because of logistical concerns (n = 2 in GC areas). Of the sampled clusters, 37 were in GC areas and 33 in non-GC areas. We substituted the nearest accessible village in eight clusters, five in GC areas, all due to logistic barriers and three in non-GC areas, all due to security concerns. The median distance of the substitutes was 16 km (range 15–45 km) to the selected cluster in GC areas and 10 km (range 9–25 km) in the non-GC areas. Active combat between armed groups was reported in 22 of 33 (66.7%) non-GC clusters and 0 of the GC clusters. Of the 22 non-GC clusters with active combat, 19 local chiefs reported involvement with “Russian” groups.We visited 856 households, of which 699 (81.6%) were included in the study. Of 352 households visited in the non-GC areas with a team leader, we recorded 22 (6.3%) absent and 0 refusals. Of 504 households visited in the GC areas with a team leader, we recorded 124 (24.6%) absent and 11 (2.2%) refusals. The median non-GC household size was 6 people . The median GC household size was 7 people . Interviewed households included 5,070 individuals present at some point in 2022, 2,168 in the non-GC areas and 2,902 in the GC areas.p-value < 0.001). Females made up 50.8% (95%CI: 49.4–52.2) of the total population, 50.5% (95%CI: 48.4–52.6) in the non-GC areas and 51.0% (95%CI: 49.1–52.8) in the GC areas . Children < 5 years old comprised 17.1% (95%CI 16.1–18.2) of the total population, 18.0% (95%CI 16.4–19.7) in the non-GC areas, and 16.3% (95%CI: 15.0–17.7) in the GC areas . Figure The median age of the study population was 15 (IQR: 6–30). See Fig. p-value: 0.06). The remaining pregnancies resulted in a birth (Table There were 157 reported pregnancies in the non-GC areas and171 in the GC areas in 2022. The crude birth rate was 39.0 (95%CI: 28.6–49.3) per 1000 per year in the non-GC areas and 46.1 (95%CI: 36.2–55.9) in the GC areas. The overall birth rate was 42.6 (95%CI 35.4–59.7). Of the population surveyed, 4.0% (n = 79) of females were currently pregnant in the non-GC areas and 2.4% (n = 64) in the GC areas. Of the reported pregnancy outcomes, 25.5%  resulted in a pregnancy loss across the survey (32.1% (95%CI: 22.5–43.4) in the non-GC areas and 19.6% (95%CI: 13.1–28.4) in the GC areas, p-value 0.48).There were 115 deaths in the non-GC areas and 105 deaths in the GC areas Table . We estip-value: 0.14). Of deaths, 50.0% (95%CI: 43.3–56.7) were reported to have sought care, without significant differences between the strata .The leading reported cause of death overall in both strata was malaria/fever, comprising 18.6% (95%CI 14.0–24.4) of all deaths: 18.3% (95%CI: 12.2–26.5) in non-GC areas and 19.0% (95%CI: 12.6–27.8) in GC areas. In the non-GC areas, the second and third leading reported causes of death were diarrhea/vomiting (9.6% (95%CI: 5.3–16.5) and hernia (8.7% (95%CI: 4.7–15.5). In the GC areas general pain/sickness was the second leading reported cause of death (9.5% (95%CI: 5.2–16.9) with diarrhea/vomiting and non-communicable diseases tied for third (7.6% (95%CI: 3.8–14.6). Of all deaths, 47.5% (95%CI: 40.8–54.3) died at home, 44.8% (95%CI 38.1–51.6) died at a health facility, 2.3% (95%CI 1.0–5.5) died en route to a health facility, and 5.4% (95%CI: 3.1–9.3) died in another location. These proportions were similar for non-GC and GC areas in Table p-value: < 0.001) and children . Of all households, 82.3% (95%CI: 79.4–84.9) reported ≤ 1 meals a day for adults and 72.6% (95%CI: 69.4–75.6) reported ≤ 1 meals a day for children. When households were asked if they would like to share any additional information, the most mentioned subjects were needs related to health (26.9%), food (25.2%), and lack of money (11.3%).Households reported a reduction in the number of meals eaten per day before versus after the crisis for adults  estimate off by four-fold, is this survey measurement incorrect, and is the extremely high mortality caused by recent events?Keuhne et al. described a large body of work suggesting that the UN mortality estimate is implausibly low . Table 4Table The 2010 MICS survey done jointly with UNICEF and the Bangui Government, which produced the last official UN CMR national estimates we have seen, sampled only areas controlled by the government, and only from villages reachable by vehicle. In rural areas of our survey, teams with motorcycles were 2.6 times more likely to reach the sampled location than a vehicle. Further undermining the 2010 MICS survey’s credibility are reports that in some places interviewers were accompanied by armed military escort, an act which would refute any claim of neutrality in the findings. . Given the significance that measures of mortality play in identifying humanitarian emergencies, this survey, conducted by a small, regional NGO with a total budget of $50,000, raises the question: are there better ways to bring global health crises to the world’s attention?There are several major limitations to our survey. We missed 10 of 80 clusters selected, three in the GC areas, seven in the non-GC. Most of these were missed due to insecurity, meaning the most at-risk populations were not included. Secondly, a similar survey in DRC documented survivor bias from deaths in households that had dissolved, which we would have missed . A largeIn answer to the last question posed above: the evidence suggests things may indeed have gotten worse over the last two years. When speaking of the present crisis, respondents referred to one of two things that developed in 2020. In the GC areas, many associate the present crisis with the arrival of COVID and its associated disruptions as well as the efforts of  the Wagner Group to regain national territory after a decades-long hold by rebel groups. , 5. TherIt is difficult to articulate the suffering associated with this elevated mortality. Many indicators aside from the death rate confirmed or validated the severity of the crisis. We ended each interview with an open-ended inquiry asking if respondents had additional information to share. Most people expressed that they were desperate for assistance, asking for health care 26.9%) and food (25.2%). In this region, it is unusual to have more deaths reported in households than births as  we measured in this survey. A disturbing 82.3% of households reported adults ate ≤ 1 meals per day at the time of interview. Similarly, 72.6% of children, who have greater nutritional needs and are at higher risk for malnutrition and its associated morbidities, ate ≤ 1 meals per day at the time of interview. The demographic profile of children under 10 (see Fig. 6.9% and Humanitarian actors have been raising the alarm of the severity of the situation in CAR for over a decade . The UN Given the United Nations’ apparent gross under-estimate of deaths in CAR, there is a need for an independent, experienced group with no direct association with the UN or warring parties to confirm this mortality finding.There is a desperate need for food aid in the form of general distributions in CAR, along with the accompanying work programs, seed and tool distributions needed to restart local economies. This is of particular importance in rural areas outside of the Government control. WFP and several NGO’s have been doing this well. Their efforts were greatly appreciated by the 18% households that received aid in 2022. Despite this, the crisis level mortality rate suggests that the needs in CAR are being largely unmet.This study cannot distinguish the relative importance of decades of ongoing conflict, extreme poverty, the economic disruptions since 2020, or the widespread disruption efforts of the Wagner Group in causing the extreme mortality observed in CAR. Thus, the following measures seem paramount, with little chance of regret.


Neonatal deaths account for the majority of deaths in the first year of life. Life-threatening apnoea or cardiovascular collapse needs cardiopulmonary resuscitation. Technological advancements, such as the administration of antepartum steroids, replacement of surfactants, nasal continuous positive airway pressure, and mechanical ventilation have led to improved neonatal survival, especially for premature neonates. The aim of this study was to find out the mean duration of mechanical ventilation among newborns admitted to the Neonatal Intensive Care Unit in a tertiary care centre.A descriptive cross-sectional study was conducted from 15 November 2020 to 15 April 2021 in a tertiary care centre. Ethical approval was taken from Institutional Review Committee (Reference number: F-NMC|504|076|077). The neonates of gestational age between 27-37 weeks of gestation admitted to the Neonatal care unit were included in the study. Neonates with birth weight <500 g and those babies having major, surgically uncorrectable lethal anomalies were excluded from the study. Convenience sampling method was used. Point estimate and 95% Confidence Interval were calculated.Among 86 neonates, the mean duration of mechanical ventilation was 2.19±1.42 days. The mean weight of neonates was 2.63±0.81 kg. A total of 71 (82.56%) were male and 15 (17.44%) were female.The mean duration of mechanical ventilation among newborns admitted to the neonatal intensive care unit in a tertiary care centre was lower than in other studies conducted in similar settings. According to the Nepal Demographic and health survey 2016 (NDHS 2016), neonatal mortality has decreased from 33 per 1000 live births to 21 per 1000.2 Technologic advancements, such as the administration of antepartum steroids, replacement of surfactant, nasal continuous positive airway pressure (nCPAP), and mechanical ventilation have led to improved neonatal survival, especially for premature neonates.3 Improving intensive care facilities for neonates in the country could be one of the effective interventions to achieve the global target of reducing under-five mortality by two thirds.2Critically sick neonates, who develop life-threatening apnoea or cardiovascular collapse, need cardiopulmonary resuscitation. Infants with progressive respiratory distress with impending respiratory failure or tiring respiratory muscles can be supported and saved by assisted ventilation facilities.The aim of this study was to find out the mean duration of mechanical ventilation among newborns admitted to the Neonatal Intensive Care Unit in a tertiary care centre.This descriptive cross-sectional study was conducted from 15 January 2021 to 15 April 2021 at the neonatal intensive care unit of National Medical College, Bhediyahi, Birgunj, Nepal after obtaining ethical approval from the Institutional Review Committee (Reference number: F-NMC|504|076|077). The neonates of gestational age between 27-37 weeks of gestation admitted to the Neonatal care unit were included in the study. Neonates with birth weight <500 g and those babies having major, surgically uncorrectable lethal anomalies were excluded from the study. Convenience sampling method was used. The sample size was calculated using the following formula:Where,n = minimum required sample sizeZ = 1.96 at 95% Confidence Interval (CI)4p = standard deviation is taken as from published literatureq = 1-pe = margin of error, 1%The minimum required sample size was 36. However, the final sample size taken was 86. The available demographic and clinical parameters were recorded as per the proforma.Data were entered and analysed using Microsoft Excel 2016. Point estimate and 95% Confidence Interval were calculated.Among 86 neonates, the mean duration of mechanical ventilation was 2.19±1.42 days. The mean weight of neonates was 2.63±0.81 kg. The majority 71 (82.56%) were male and 15 (17.44%) were female. The mortality was 28 (32.56%) .5 In our study total of 71 (82.56%) were male and 15 (17.44%) were female, and other similar studies found that 78 (55.3%) were male and 63 (44.7%) were female.5 The mean weight of neonates was 2.63±0.81 kg in our study. Similar to our study, the mean birth weight was found to be 2779.37±827.06 g in another study,5 and weight was 2000±690 g in another similar study.6In this study, the mean duration of mechanical ventilation was 2.19±1.42 days which is lower than the other similar study.6 similarly 6.83% of neonates required mechanical ventilation in another similar study.7 In addition to this another study found 30.7% of neonates were ventilated,8 and another study found 72 neonates required mechanical ventilation.9 Our study has found that 52.32% of the mechanically ventilated newborn has underlying perinatal asphyxia however similar study found that RDS (58.9%) was the most common indication for mechanical ventilation.5 In our study, hypoxic-ischemic encephalopathy was present in 48.84% of neonates which is lower in comparison to another study in which prevalence was 20.2%.8In our study a total of 86 neonates were ventilated. Similar to our study, other studies conducted found that out of 50 neonates were ventilated in the study,6 Pneumothorax was present in 1 (1.16%) another similar study found the prevalence to be 4.96%.5 In our study, the prevalence of hypoxic-ischemic encephalopathy was 42 (48.84%), which is higher than a similar study in which the prevalence was 12.5%.9 In our study congenital heart disease was present in 1 (1.16%) similarly in another study it was about 4.96%.5 Meconium aspiration syndrome was present in 13 (15.12%), which is lower than one of the similar studies.9 In our study, mortality was 28 (32.56%) similar to this the mortality was found to be 48.2% in a study.5In our study, asphyxia was present in 45 (52.32%) which is higher than the other similar study in which asphyxia was present in 24%.The limitation of this study is that since it is a singlecentered descriptive cross-sectional study, the result cannot be generalised and the outcomes could not be analyzed with analytical parameters.The mean duration of mechanical ventilation among newborns admitted to the neonatal intensive care unit in a tertiary care centre was found to be lower than in other studies conducted in similar settings.


Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. Serum lactate is useful in predicting the prognosis of critically ill patients. Elevated blood lactate levels as well as delayed clearance have been linked to higher mortality in sepsis. Shock index is a simple and effective bedside assessment means of gauging the degree of shock and is an important predictor of identifying high-risk patients. Monitoring lactate levels may aid clinicians in understanding tissue perfusion and detecting unrecognized shock and making prompt therapy adjustments. This study aimed to find out the mean serum lactate levels in patients with sepsis presenting to the Department of Emergency Medicine of a tertiary care centre.A descriptive cross-sectional study was conducted at a tertiary care centre among the patient with sepsis presenting to the emergency department from 1 September 2022 to 30 November 2022. Ethical approval was obtained from the Institutional Review Committee of a tertiary care centre (Reference number: 26082022/02). History taking and detailed examination were done. Blood was sent for serum lactate and other parameters as proforma was sent. The shock index was calculated. Convenience sampling was done. Point estimate and 95% confidence interval were calculated.Among 53 sepsis patients, the mean serum lactate level in sepsis patients was 2.84+2.02 .The mean serum lactate level in patients with sepsis is similar as compared the studies done in similar settings. As a result, in critically ill patients, serum lactate levels serve as a diagnostic sign.2Sepsis is the leading cause of death in hospitals, and it frequently causes multi-organ dysfunction as a result of a culture-positive or negative infection. Serum lactate levels of >2 mmol/l may be essential signs of septic shock.3 Monitoring lactate levels may aid clinicians in understanding tissue perfusion and detecting unrecognized shock, and necessary interventions can be done timely.4 Only a few research studies have been conducted in Nepal.Sepsis and its consequences, are a menace in countries like ours. Early diagnosis and treatment help to reduce morbidity and mortality.This study aims to find the mean serum lactate levels in patients with sepsis presenting to the department of emergency medicine of a tertiary care centre.A descriptive cross-sectional study was conducted after obtaining ethical approval from the Institutional Review Committee of Kathmandu Medical College Teaching Hospital (Reference number: 26082022/02). Data were collected from 1 September 2022 to 30 November 2022. The study population included all patients who presented to the Emergency Department and have been diagnosed to be a case of sepsis. The patients who require immediate referral to another centre, patients who leave against medical advice (LAMA), patients who do not consent to participate in the study, and confounders of raised serum lactate will be excluded from the study. Convenience sampling method was used. The sample size was calculated by using the following formula:Where,n = minimum required sample sizeZ = 1.96 at 95% Confidence Interval (CI)5σ = standard deviation is taken as 2.46 from published literaturee = margin of error, 1%1Thus, the calculated minimum required sample size was 48. The sample size was 27 after adding of 10% non response rate. However, sample size of 53 was taken. Serum lactate level >2 mmol was considered high serum lactate level.Data were entered in Microsoft excel 2016 and analyzed using IBM SPSS. Point estimate and 95% CI were calculated.Among 53 sepsis patients, the mean serum lactate level in sepsis patients was 2.84+2.02 . Out of those patients, males were 30 (56.60%) and female were 23 (43.39%) with male to Female ratio of 1.3:1. Out of 53, 15 (28.30%) male and 13 (24.53%) female patients had low lactate levels .Mean age of patients with high serum lactate level was 49.56±20.29 years .Patient diagnosed clinically in shock while categorizing with SI index, 3 (5.66%) had severe shock .Among 53 patients, 25 (47.17%) patients with high lactate levels presented in shock with high SI .Sepsis is a major problem in the emergency department since it has high morbidity and mortality.5 Out of 30 male patients, 15 of them had low lactate levels (lactate level < 2.5 mmol/L), 9 had intermediate lactate levels (2.5 to 3.99 mmol/L) and 6 had high lactate levels (> 4 mmol/L). Among 23 female patients, 13 had low lactate levels, 6 had intermediate lactate levels and 4 had high lactate levels.Among 53 sepsis patients, the mean serum lactate level in sepsis patients was 2.84+2.02 which is similar to other study.6 On comparing the normal and abnormal lactate levels according to gender, the above study showed that among total females, 13.1% have normal lactate levels and 86.9% have abnormal while in males, 7.1% have normal lactate levels and 92.9% have abnormal,6 unlike our study which showed that 56.5% of females have normal lactate level with 43.5 having abnormal and for males, the percentage is equally divided into halves.A similar study was done in Patan Hospital in a total of 94 patients which showed abnormal Lactate levels in 80% among which 29% had intermediate lactate levels and half of them had high lactate levels which were unlike our findings which showed that 28.3% had intermediate and 18.9% had high lactate level.6 However, contrary to this, another study shared that the maximum patient has intermediate lactate levels (45.3%).7A study revealed a result similar to our study which showed that the maximum number of patients (49.9 %) had low lactate levels, with ours being 52.8%.8Shock index (SI), is a simple and effective bedside assessment means of gauging the degree of shock and is as defined as heart rate divided by systolic blood pressure (SBP) with a normal range of 0.5 to 0.7 in healthy adults. SI is inversely related to physiological parameters and SI ≥ 1.0 is associated with significantly poorer outcomes in patients with shock.9In a previously done study, subjects with a shock index of 0.7 or greater (15.8%) were 3 times more likely to have hyperlactatemia than those with a shock index of less than 0.7 (4.9%).9 The result of our study varied from these. In our study, 27 out of 28 patients with normal lactate levels presented in shock (High SI) whereas all 25 patients with abnormal lactate levels presented in shock. Despite the conflicting results, we can conclude shock index can be used to predict hyperlactatemia. In our study, 1 (1.89%) patient was found to have presented in no shock (less SI), 22 (41.50%) patients presented in mild shock, 23 (43.4%) patients presented in moderate shock and 7 (13.20%) patients presented in severe shock.The study showed that patients with a normal SI (less than 0.7) are 95% likely not to present with an established marker for severe sepsis-a high lactate level.There were limitations to our study as we could not obtain the measurement of serial lactate levels due to financial constraints. Similarly, we could not obtain data related to medication use which could invariably affect the patient's vital signs. Our study mostly included patients of the older age group, which is a vulnerable population to severe forms of the disease. As this is a single-centred study, the results may not be generalized to all the patients with shock.The mean serum lactate level in patients with sepsis is lower than in the studies done in similar settings. Patients with normal lactate levels were also found to have high SI. Clinical diagnosis with SI index in conjunction with Serum lactate evaluation would be beneficial for the proper diagnosis of Sepsis.


Hepatitis B vaccination is recommended for all children at birth within 24 hours or during childhood.This study was aimed to evaluate protective efficacy of hepatitis B vaccine and estimate the sero-prevalence of hepatitis B virus infection among vaccinated children.A community-based cross-sectional study was conducted from March, 2021 to October, 2021 in Debre Markos town. A simple random sampling technique was used to select 165 fully vaccinated children aged 5–12 years old. A serum sample was used to determine hepatitis B surface antigen (HBsAg), anti-hepatitis B core antibody (anti-HBc), anti-hepatitis B surface antibody titer (anti-HBs) using ELISA.The seroprevalence of HBsAg and anti-HBc anti-body was found to be 4.2% and 4.8% respectively. Of 165 fully vaccinated children, 129 (78.2%) had anti-HBs titer ≥ 10 mIU/ml. Among 129 sero-protected children, 76 (58.9%) were hypo-responders whereas the rest 53 (41.1%) were good responders. Those children within the age group of 5–7 years were 2.9 times  (P<0.023) more likely to respond to HBV vaccine. Multivariate logistic regression revealed that children who were born from HBV positive mothers  and those who had history of injectable medications  were more likely to be HBsAg positive. Children who had history of hospital admission  were more likely to be anti-HBcAb positive.There was an intermediate prevalence of childhood HBV infection despite being vaccinated suggesting low protective efficacy of hepatitis B vaccine in the study area. According to the World Health Organization, one-third of the global population has serological markers of active HBV infection. More than 350 million are chronic carriers with HBV –3 and 1.Nowadays, about 194 countries have performed HBV vaccination program for infants . After cDue to those factors, 15–50% of the vaccinated children may have undetetctable concentrations of anti-hepatitis B surface antibody after 5–15 years of vaccination and 10% still could be susceptible to HBV infection , 20. In A community-based cross-sectional study was conducted among hepatitis B vaccinated children in Debre Markos town, Amhara regional state, Northwest Ethiopia, from March 2021 to October 2021. Based on the report from East Gojjam Zone administrative office, the number of children < 15 years was 18,345 of which the number of girls and boys were 10,020 and 8,325 respectively.All hepatitis B fully vaccinated children whose ages were from 5–12 years and live in Debre Markos town were considered as source population and those hepatitis B fully vaccinated children whose ages were from 5–12 years, who fulfilledeligibility criteria and were found at home during the data collection period were taken as study population. All hepatitis B vaccinated children who volunteered to participate in the study, whose parents or legal guardians volunteered to give assent and those children who took full dose of hepatitis B vaccine [as evidenced by showing vaccination card] were included in the study. Those study participants who did not complete the full dose of the hepatitis B vaccine, who or whose parents were severely sick  during the data collection period and could not give blood samples were excluded from the study.The sample size was calculated using single population proportion formula by taking 89% (0.89) of the prevalence in vaccine response derived from a study done in Addis Ababa, Ethiopia . By cons2/ (0.05)2 *0.89*0.11 = 150n = (1.96)Wheren = sampleZ = 1.96 at 95% C.Ip = prevalence = 0.89q = 1-p = 1–0.89 = 0.11d = margin of error = 0.05Non-response rate = 10% of 150 = 10%*150 = 10 ∕ 100*150 = 15Therefore, the final sample size (n) was calculated as n = 150+15 = 165.Simple random sampling technique was used to recruit the study participants from March, 2021 to October, 2021 until the required sample size was obtained among hepatitis B vaccinated children at the selected kebeles in Debre Markos town. Debre Markos Town has 11 kebeles out of them 5 kebeles (45%) were selected by lottery method so as to keep representativeness. Then total sample size was allocated proportionally to each kebeles depending on the total number of vaccinated children from 5 to 12 years of age. One child was selected randomly (lottery method) from those households having two and more children.After the participant’s family agreed to take part in the study and signed on informed written assent form, socio-demographic characteristics and associated factors data were collected by using a pretested semi-structured questionnaire. Each child’s weight and height were measured and body mass index was calculated in percentile. Authors were blind and had no information about the study participants during or after data collection.https://www.bio-rad.com/].Five ml of venous blood was aseptically collected from each study participant from March, 3/25/2021 to October, 10/5/2021 and transported to Debre Markos blood bank laboratory within one hour. Serum was then separated by centrifugation, and stored at -20°C until transported to Armauer Hansen Research Institute (AHRI) for analysis. Serum level of HBsAg, anti-HBcAb, and anti-HBs were determined using sandwich Enzyme-Linked Immunosorbent Assay (ELISA), where antigens/monoclonal antibodies were used both for capture and detection . For the determination of anti-HBs level, quantitative type of sandwich ELISA was used. The test kits have a clamed sensitivity of 100% and specificity of 99.28%. Each test procedure was performed according to the manufacturer’s instruction [After checking the data completeness, data were entered into- Epidata software version 3.1 and exported to SPSS software version 25 for analysis. The results were presented as tables and figure. Binary logistic regression was used to show the association between dependent and independent variables. In bivariate logistic regression, a p-value <0.25 were candidates for multivariate logistic regression. Multivariate logistic regression was used in terms of adjusted odds ratio (AOR) with 95% confidence intervals and a p-value < 0.05 was considered statistically significant.This study was ethically approved by the research and ethical committee of College of Health Science, Debre Markos University with reference number (HSC/R/C/Ser/PG/CO/277/12/13). It was performed in accordance with the relevant guidelines and regulations. Written informed assent was taken from the participant’s guardian and consent was obtained from all participants.A total of 165 children with the age range of 5–12 years participated in this study. The median age of the study participants was 8.00 ± 2.58. About 45.5% of the study participants were found within the age group of 5–7 years and the majority of them 89/165 (53.9%) were males. One hundred and fifty (90.9%) of participants were from urban area .The overall positivity of HBsAg among all study participants was 7/165 (4.2%) (95% CI: 1.0–5.0). Of seven children who were positive for HBsAg, 6/7 (85.7%) of them were males. Furthermore, the prevalence of HBsAg positivity in 5–7 years children was 5/7 (71.4%). The overall prevalence of anti-HBc antibodies among the study participants was 8/165 (4.8%) (95% CI: 2.0–6.0). From the total prevalence of anti-HBc antibodies, 4/8 (50.0%) was from female participants. About 4/8 (50.0) % anti-HBc antibody prevalence was from children whose ages were found within the age group of ≥ 11 years .Of the total prevalence of HBsAg, about 14.3% was from children who were born from mothers with previous history of HBV infection. The prevalence of HBsAg among obese children was 2/7(28.6%). The prevalence of anti-HBc antibody among children with previous history of injectable medication was 1/8(12.5%) .Among vaccinated children, 129/165 (78.2%) (95% CI: 72.0–85.0%) of them had anti-HBs titer ≥ 10 mIU/ml. Out of this, 76 (58.9%) were hypo-responders (with anti-HBs titer of 10–100 mIU/ml) whereas the rest 53(41.1%) were good responders (with anti-HBs titer of >100).In multivariable logistic regression, children born to mothers with HBV infection were 3.9 times  (P<0.027) more likely to be HBsAg seropositive as compared to those who were born to mothers without previous history of HBV infection. Children who had previous history of injectable medications were 9 times  (P<0.016) more likely to be HBsAg positive than those without previous history of injectable medications . MoreoveIn multivariate logistic regression, children who were found within the age group of 5–7 years were 2.9 times  (P<0.023) more likely to respond to HBV vaccine as compared to those whose ages were > 7 years.The overall sero-positivity of HBsAg among vaccinated children from 5–12 years was 4.2% (95% CI: 1.0–5.0). This result tells us the study area is found under the category of intermediate endemicity for HBV infection . This fiPrevious history of child’s mother for HBV infection and child’s injectable medications were identified as important determinants for HBV infection. This is in accordance with the findings reported from Hawassa . This miThe overall seroprevalence of anti-HBc positivity in this study was 4.8% (95% CI: 2.0–6.0) which is comparable with previous results reported from Addis Ababa (5.6%)  and GondThe seroprotection level of hepatitis B vaccine among 5–12 years children in this study was 78.2% (95% CI: 72.0–85.0%) which is low since safe and effective HBV vaccine has a protection level of 98 to100% according to WHO report . This fiThe protective levels of HBV vaccine in this study seemed higher among females than males (53.5 vs 46.5%) though not statistically significant and is in agreement with the study conducted in Yemen (75.7% vs 68.4%) , and AddIn conclusions, the seroprevalence of hepatitis B infection was intermediate among vaccinated children in the study area. Mother’s HBV status was significantly associated with HBsAg positivity. There should be regular early screening of vaccinated children for HBV infection. The protective efficacy of HBV vaccine in the present study was low. Thus, determination of levels of anti-HBs antibodies should be done, and then booster doses must be given for non-responders to increase the concentration of anti-HBs levels and prevent waning immunity.Limitations of the study: Even though this study has paramount public health importance, it was done with small sample size. As a result, it is difficult to infer seroprevalence of HBV infection and seroprotection of HBV vaccine to the entire population with this sample size.S1 Data(SAV)Click here for additional data file.


The adhesive progestin patch was investigated for estrus synchronization in mares because this method is convenient and safe in other species. This study aimed to compare the efficacy of a transdermal progestin patch versus oral altrenogest on estrus synchronization, preovulatory follicle development, and ovulation.Twenty-four broodmares were randomly divided into two groups. In Group 1, mares (n = 12) were fed 0.044 mg/kg altrenogest daily for 14 days. Group 2 (n = 12) mares were treated with adhesive transdermal progestin patches for 14 days. Mares were observed for estrus daily, from day 3 until day 7, after hormone withdrawal. Follicular development was determined by ultrasonography. The preovulatory follicle size and ovulation time after hormone treatments and ovulation rate were determined for both groups. Plasma progesterone levels were measured during the experimental periods and 2 days after hormone termination in both groups.The results revealed that the transdermal progestin patch efficiently controlled follicular growth and estrus synchronization in mares. The percentage of mares exhibiting estrus was similar in the altrenogest (100.00%) and transdermal patch (91.67%) groups. Ovulation rates were equivalent with either altrenogest or progestin patch protocols (91.67% [11/12] vs. 83.33% [10/12]). In addition, the preovulatory follicle size was similar in mares treated with altrenogest and progestin patches.This study revealed that the transdermal progestin patch provides effective estrus synchronization and ovulation, similar to altrenogest treatment. However, the transdermal patch was more convenient with a shorter predictable ovulation time after estrus synchronization and should be considered as an alternative method for mares. Before ®; 0.4% weight/volume, MSD Animal Health, New Jersey, The United States) at 0.044 mg/kg of body weight once a day for 14 days. Group 2: the remaining 12 mares were treated with adhesive transdermal progestin patches  for 14 days, placed on the skin at the ventral side of the proximal part of the tail. Two adhesive patches were used for Group 2 animals, with one patch used for 7 days then removed and immediately replaced with a second patch for another 7 days of treatment, resulting in a total treatment of 14 days. The adhesive area was chosen because the skin had less hair, was soft and thin, and the patch could be easily pasted. Finally, patches were covered with adhesive tape to protect them from urine and feces during treatment. The examination of any complications of altrenogest and progestin patch treatments included examination for the presence of obvious allergic reactions as well as the skin at the adhesive area immediately after the withdrawal of altrenogest or patches. A diagram of the experimental design is shown in Twenty-four broodmares were randomly assigned to two equal groups. Group 1: 12 mares were fed with altrenogest  sample progesterone levels were measured using a direct radioimmunoassay and Danazol® Reagent  as a displacing agent. In addition, plasma samples were tested in the three pools  of the progesterone standard. The intra- and inter-assay coefficients of variation for the three pools were 8.03%, 9.95%, and 8.50% (intra), and 19.00%, 18.80%, and 11.73% (inter), respectively. The sensitivity threshold of the test was <0.01 ng/mL.Daily blood samples  were collected from all mares of the two groups for 17 days to measure the plasma progesterone levels. The sample collection was started on day 0, which was the day before hormonal treatment (start of both treatment groups), continued on day 1 to day 14 , and through days 15 and 16 . All the blood samples were stored on ice and transported to a laboratory at the Research and Development Centre for Livestock Production Technology, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand. Blood samples were centrifuged at 3000× et al. [et al. [After the termination of hormone treatment in mares, the estrus response in all mares of both groups was examined using transrectal ultrasonography. The detection of uterine endometrium edema (Grade 1 from 4) and a dominant follicle (diameter of approximately 35 mm) in both ovaries indicated a mare in estrus according to studies of Canisso  [et al. . For the2 test with or without Yates correction. An independent t-test was used to compare the means (±SD) of preovulatory follicle sizes and the number of days to ovulation after hormone treatments. Furthermore, the plasma progesterone concentrations in both groups were analyzed using a linear mixed model procedure. A probability of p ≤ 0.05 was considered significant. All statistical analyses were performed by Program R .The data obtained for follicle development were descriptively expressed. The estrus, complication, and ovulation rates were statistically assessed using the χA total of 12 mares  showed an estrus response (uterine endometrium edema and dominant follicles) about 3–5 days after altrenogest withdrawal. In comparison, the estrus response was observed in 11 mares  3–5 days after the removal of transdermal progestin patch treatment.The estrus rates of Groups 1 and 2 were not significantly different. The recruited dominant follicles of mares in estrus in both groups were observed until ovulation or 10 days after altrenogest or progestin withdrawal. The ovulation rates (ovulation numbers) of mares in estrus in Groups 1 and 2 were 91.67% (11/12) and 83.33% (10/12), respectively, and were not significantly different. The average maximal diameters (mean ± SD) of the largest preovulatory follicles about 1 day before ovulation in Groups 1 and 2 were 41.56 ± 0.74 mm (n = 11) versus 40.49 ± 0.84 mm (n = 10), respectively, and were not significantly different.The patterns of dominant follicular development in terms of average diameter, from approximately 35 mm until the largest preovulatory follicle before ovulation, of mares in estrus are presented in After hormone treatments, the mares in the altrenogest and progestin patch treatment groups did not have any complications, such as purulent discharge or any clinical signs related to pyometra or vaginal infection, and their obvious allergic reactions and inflammation or irritation of skin on treatment areas continued after patch removal. For mares in Group 1, the mean (±SD) plasma progesterone concentration was 6.15 ± 1.30 ng/mL on day 1, then reached the highest level at 6.88 ± 0.92 ng/mL on day 4, followed by 6.21 ± 1.03 ng/mL on day 5 and quite stable high levels until 5.26 ± 0.85 ng/mL on day 14 of hormone treatment. The progesterone levels decreased to 1.15 ± 0.35 and 0.67 ± 0.21 ng/mL on day 15 and 16 . For mares in Group 2, the mean (±SD) plasma progesterone concentration was 5.03 ± 0.58 ng/mL on day 1 and then achieved the highest level of 5.17 ± 0.52 ng/mL on day 3, then 4.66 ± 0.69 ng/mL on day 4, and quite stable at moderate levels until 3.92 ± 0.65 ng/mL on day 14 of patch treatment. One–2 days after patch removal, progesterone levels decreased to 1.34 ± 0.90 and 1.05 ± 1.19 ng/mL, respectively. The mean plasma progesterone concentrations were significantly different for mares in Group 1 versus Group 2 during hormone treatments (from day 1 until day 14), as shown in 2α [The methods of synchronization in this study were excellently successful due to the mares in both groups that had high estrus and ovulation rates. The reason might be that this study was conducted in a season with long days, when photoperiod influenced the endogenous reproductive hormones and enhanced ovarian activity along with synchronization. According to a previous report by Crabtree , the rep2α .et al. [et al. [et al. [The results showed that altrenogest (synthetic progestin) was effective for estrus synchronization and ovulation in broodmares, which is consistent with previous studies by Bergfelt et al. , Hodgson [et al.  and Loy  [et al. . On the  [et al. , 21. Theet al. [2α, mares treated with altrenogest exhibited estrus after progestin removal, consistent with the reported effects of altrenogest [et al. [et al. [In addition, the use of progestin patches did not adversely affect reproductive organs nor lead to inflammation of skin at the adhesive areas. The exogenous progestin patch treatment and traditional oral altrenogest protocol had comparable efficacy at inducing estrus in mares, but the patch method was simpler than oral altrenogest, which had to be fed to mares daily for 14 days. Moreover, the patch had no complications compared with intravaginal progesterone-releasing devices [et al.  using threnogest –8. Howevrenogest . The folrenogest . With threnogest . The pre [et al. . The pre [et al. .et al. [et al. [et al. [However, the mean number of days to ovulation after withdrawal of progestin patch treatment was shorter than for the mares in the altrenogest group. One reason may be the lower plasma progesterone concentrations for mares in the progestin patch group (from day 1 until day 14 of treatment) compared with the altrenogest administration group. Altrenogest promoted higher plasma progesterone concentrations during treatment, thereby postponing the ovulation time in mares, consistent with the efficiency of oral progestin reported in previous studies by Canisso  [et al. . The pre [et al. , showing [et al. . The tra [et al. , 24.et al. [The results analysis of this study showed that the plasma progesterone level pattern following oral altrenogest treatment was similar to that of a prior study . As a reet al.  using prα2 should be used immediately after patch removal so that the timing of estrus and ovulation rates in mares are similar to those in a previous report by Ginther et al. [α2 protocol. The present study suggests that the progestin absorbed from dermal patch could effectively synchronize estrus and ovulation without affecting fertility. However, further studies should inseminate mares without initial detection of estrus and then after estrus and ovulatory synchronizations by the progestin patch and evaluate pregnancy rates using this treatment protocol.On the other hand, oral altrenogest could have a fast effect and a higher plasma progesterone concentration because it might be absorbed from the intestine to the bloodstream as well. However, using progestin patches during 14 days for estrus synchronization in mares was not the most convenient method, because the adhesive patches were replaced after 7 days. Thus, the use of progestin patches in short protocols (for 7 days) may be more convenient, but PGFr et al.  using prOverall, this study revealed that the progestin patch protocol maintained the ability to recruit the dominant follicle. The transdermal progestin patch had a similar efficiency compared with the oral altrenogest protocol in terms of estrus and ovulation synchronizations. Even though there are a number of altrenogest products available now, including oral, injectable, transrectal, and transvaginal administrations, they are still impracticable to use for synchronizations in mares. Furthermore, the FDA  is awareThis study revealed that altrenogest and the transdermal progestin patch could efficiently synchronize estrus and control follicle development until ovulation. Conversely, the transdermal patch was more practical for mares because it had quicker, more predictable ovulation timing after estrus synchronization. Further studies are recommended to evaluate the use of transdermal progestin patches in timed artificial insemination and embryo transfer protocols as an alternative method to enhance reproductive performance in mares.Both authors participated in the experimental design and conducted the experiment. JK: Conducted a comprehensive literature search, analyzed the collected data, drafted, revised, and proofread the manuscript. SW: Collected the data. Both authors have read, reviewed, and approved the final manuscript.


The aim of this study was to develop and validate a commercially available AI platform for the automatic determination of image quality in mammography and tomosynthesis considering a standardized set of features.In this retrospective study, 11,733 mammograms and synthetic 2D reconstructions from tomosynthesis of 4200 patients from two institutions were analyzed by assessing the presence of seven features which impact image quality in regard to breast positioning. Deep learning was applied to train five dCNN models on features detecting the presence of anatomical landmarks and three dCNN models for localization features. The validity of models was assessed by the calculation of the mean squared error in a test dataset and was compared to the reading by experienced radiologists.Accuracies of the dCNN models ranged between 93.0% for the nipple visualization and 98.5% for the depiction of the pectoralis muscle in the CC view. Calculations based on regression models allow for precise measurements of distances and angles of breast positioning on mammograms and synthetic 2D reconstructions from tomosynthesis. All models showed almost perfect agreement compared to human reading with Cohen’s kappa scores above 0.9.An AI-based quality assessment system using a dCNN allows for precise, consistent and observer-independent rating of digital mammography and synthetic 2D reconstructions from tomosynthesis. Automation and standardization of quality assessment enable real-time feedback to technicians and radiologists that shall reduce a number of inadequate examinations according to PGMI  criteria, reduce a number of recalls and provide a dependable training platform for inexperienced technicians. Deep convolutional neural network (dCNN) models have been trained for classification of mammography imaging quality features.AI can reliably classify diagnostic image quality of mammography and tomosynthesis.Quality control of mammography and tomosynthesis can be automated. Every year, 2.3 million women are diagnosed with breast cancer  represenFor successful radiological evaluation of mammograms and tomosynthesis images, sufficient diagnostic information depicting as much breast parenchyma as possible has to be present on the two projection images. In screening programmes, quality assurance (QA) of physical and technical aspects is implemented, providing repeatable and standardized evaluations of image quality that are comparable between diagnostic units. Over the years, several QA protocols have been developed, although there is incomplete harmonization between them , 9. The k = 0.02) and fair (k = 0.40) .Depiction of parenchyma by AI models was correct in 97.1% [95% CI 96.2–97.7%] of test cases in CC view and in 87.3% [95% CI 86.3–88.2%] of test images in MLO view. In CC view precision was 0.93, recall 0.99 and F1-score 0.96. The model showed almost perfect agreement with radiologists with a Cohen’s kappa score of 0.93 [95% CI 0.90–0.95].Depiction of Inframammary fold in MLO projection was correct on 96.3% [95% CI 94.9–97.4%] of images. Precision of the model was 0.94, recall 0.99 and F1-score were 0.99. The model showed almost perfect agreement with radiologists with a Cohen’s kappa score of 0.96 [95% CI 0.94–0.98].Depiction of the pectoral muscle in CC projection was correct on 98.5% [95% CI 98.2–99.5%] of images. Precision of the model was 0.98; recall and F1-score 0.96. The model showed moderate agreement with radiologists was achieved with a Cohen’s kappa score of 0.42 [95% CI 0.34–0.50].Depiction and classification of nipple in profile in MLO and nipple in profile and centered in CC images was correct in 93.0% [95% CI 91.7–94.0%] of the evaluated cases. Precision of the model was 0.99, recall 0.94 and The regression model for nipple position detection was able to predict the position with an error of 8.4 mm [95% CI 7.3–9.5 mm].In MLO view, the cranial point of a pectoralis muscle was detected with an error of 17.9 mm [95% CI 13.2–21.0 mm] and the caudal point with an error of 13.2 mm [95% CI 9.9–16.0 mm].F1-score were 0.99 in both cases. The calculations have been compared to the evaluation performed by our experienced radiologists. For the radiologists, accuracy of the calculation was 99.0% and precision, recall and F1-score were 0.99. Agreement with radiologists was almost perfect, and Cohen’s kappa score was 0.97 [95% CI 0.95–0.99].The accuracy of the calculation of pectoralis angle was 99.1% [95% CI 98.2–99.5%] and for posterior nipple line 99.0% [95% CI 98.2–99.5%]. Precision, recall and In this study, we were able to show that deep convolutional neural networks can be used to assess quality features on mammograms and synthetic 2D reconstructions from tomosynthesis. Classification models achieved over 85% accuracy for determination of key image quality features in breast imaging. Regression models allowed for precise localization of desired features to indicate possible positioning errors. When comparing results of the test dataset evaluation, all dCNN models were able to achieve almost perfect agreement with the radiologists.In recent years, AI-based computer-aided detection solutions have attracted the attention of radiologists worldwide. A dCNN is an excellent method for image classification tasks. AI performance in breast cancer detection in mammography is comparable to experienced radiologists , 24, desCurrent studies of quality control in breast cancer diagnosis focus on quality assurance. CNNs potentially allow for automated image quality assessment according to European Reference Organization for Quality Assured Breast Cancer Screening and Diagnostic Services (EUREF) . HoweverOur study has some limitations: (1) Datasets chosen for training, validation and testing may potentially be biased due to the retrospective nature of this study. (2) Images in this study came from a limited number of manufacturers, which may have an effect on a number of possible variants of images used for analysis. However, the purpose of this study was to provide a proof-of-principle of automated quality assessment and to obtain initial experiences on achievable accuracies. (3) Not all ethnicities were included in this study; however, representative data were taken from the general cohort of female patients in our institutions. (4) In this study, no other architectures of AI algorithms have been evaluated. Therefore, it might be possible to achieve even higher accuracies with other dCNN configurations. (5) This is a retrospective study focusing on evaluation of single-quality features. To evaluate an impact of real-time feedback on the performance of diagnostic units, an additional prospective study shall be conducted.In conclusion, this study has proven the feasibility of automated assessment of quality features with the trained AI models that allow for standardization of quality control. The clinical implementation of our solution may allow for fast, observer-independent feedback to radiographers and radiologists in the assessment of the overall image quality for breast positioning. This may improve the sensitivity and specificity of examinations and reduce errors, recalls and workload for radiologists and technicians.