Contrasting Asymptomatic and Drug Resistance Gene Prevalence of Plasmodium falciparum in Ghana: Implications on Seasonal Malaria Chemoprevention.
Malaria is a significant public health problem in Ghana. Seasonal Malaria Chemoprevention (SMC) using a combination of sulfadoxine-pyrimethamine and amodiaquine has been implemented since 2015 in northern Ghana where malaria transmission is intense and seasonal. In this study, we estimated the prevalence of asymptomatic P. falciparum carriers in three ecological zones of Ghana, and compared the sensitivity and specificity of different molecular methods in identifying asymptomatic infections. Moreover, we examined the frequency of mutations in pfcrt, pfmdr1, pfdhfr, and pfdhps that relate to the ongoing SMC. A total of 535 asymptomatic schoolchildren were screened by microscopy and PCR (18s rRNA and TARE-2) methods. Among all samples, 28.6% were detected as positive by 18S nested PCR, whereas 19.6% were detected by microscopy. A high PCR-based asymptomatic prevalence was observed in the north (51%) compared to in the central (27.8%) and south (16.9%). The prevalence of pfdhfr-N51I/C59R/S108N/pfdhps-A437G quadruple mutant associated with sulfadoxine-pyrimethamine resistance was significantly higher in the north where SMC was implemented. Compared to 18S rRNA, TARE-2 serves as a more sensitive molecular marker for detecting submicroscopic asymptomatic infections in high and low transmission settings. These findings establish a baseline for monitoring P. falciparum prevalence and resistance in response to SMC over time.
['Dieng|Cheikh Cambel|CC|', 'Gonzalez|Lauren|L|', 'Pestana|Kareen|K|', 'Dhikrullahi|Shittu B|SB|', 'Amoah|Linda E|LE|', 'Afrane|Yaw A|YA|', 'Lo|Eugenia|E|']
D000962:Antimalarials D058070:Asymptomatic Diseases D018890:Chemoprevention D004351:Drug Resistance D017125:Genes, Protozoan D005869:Ghana D006239:Haplotypes D006801:Humans D016778:Malaria, Falciparum D009154:Mutation D010963:Plasmodium falciparum D015995:Prevalence D062486:Public Health Surveillance D012337:RNA, Ribosomal, 18S D012621:Seasons D012680:Sensitivity and Specificity
Plasmodium falciparum Sulfadoxine-Pyrimethamine asymptomatic infections pfdhps TARE-2 antimalarial drug resistance phdhfr quantitative real-time PCR