Estimation of Hepatitis A Virus Infection Prevalence Through Drinking Water Supply of Primary Schools of Sindh, Pakistan

Background: Hepatitis A Virus (HAV) is among the main endemic human enteric viral diseases that directly or indirectly affect children’s performance at primary schools in low-income countries. Limited information is available on the presence of HAV, with particular reference to drinking water supplies of primary schools in Sindh, Pakistan. Objectives: The present study estimated the risk of HAV infection through drinking water sources using Quantitative Microbial Risk Assessment (QMRA) in primary schools of Sindh, Pakistan. Methods: The QMRA model was applied to estimate the potential health risks of HAV using indicator organisms, i.e., fecal coliforms. Microbial analysis was conducted using a membrane filtration method. The exponential dose-response model was used to calculate the probability of infection. Results: The highest daily risk of HAV infection for schoolchildren was calculated as 35.0 per 10,000 schoolchildren in Karachi district with an annual risk of 66%, whereas the lowest risk was 3.0 per 10,000 schoolchildren in Larkana with 7.8% of the annual risk. The mortality risk due to HAV ranged from 4.0 to 29 deaths per 10,000 children per year. Conclusions: Overall, the drinking water quality of primary schools of Sindh was found very poor. The estimated daily and annual risks of hepatitis A to primary school children were moderate to high. To halt enteric virus transmission through drinking water sources, there is a dire need to invest in the provision of comprehensive water sanitation and hygiene facilities at schools.