[An outbreak of XXXX caused by contaminated well water in a village, Henan province.]

@entity1 @entity390 @entity294 @entity391 @entity1902 @entity490 @entity526
OBJECTIVE: To identify the cause and mode of transmission of a @entity1902 outbreak in a village, Henan province. METHODS: @entity1902 @entity1 were identified through family visits, interviewing the village doctors and reviewing diagnosis and prescription records at the village health clinic. Cases were defined as onset of one of the four symptoms from the village resident during July 20 to August 12, 2010. The symptoms would include @entity294 (>=  3 times/day), @entity490 , @entity390 or @entity391 . A retrospective cohort study was conducted to assess the association between drinking raw well water or eating noodles rinsed by raw well water and @entity1902 . @entity391 of the case- @entity1 and the well water samples were tested for bacterial pathogens. RESULTS: Data for 60 case- @entity1 were collected. All cases occurred in the northern part of the village. @entity1 who used water from a public well in the northern part of the village had an attack rate of 55%, which was 3.5 times of those who did not use the well water (16%) (RR = 3.5, 95%CI: 1.2 - 10). Results from the retrospective cohort study showed that drinking un-boiled water from the well was a risk factor (RR = 1.7, 95%CI: 1.3 - 2.3). Laboratory testing showed that total coliform and @entity526 both greatly exceeded the limit considered safe for drinking, indicating there was fecal contamination in the well water. No bacterial pathogens were detected in the @entity1 ' @entity391 . CONCLUSION: The outbreak was mainly caused by drinking contaminated water from the public well in the northern part of the village.
