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

Abstract

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.

Drinking Water Quality Mapping Using Water Quality Index and Geospatial Analysis in Primary Schools of Pakistan

“…In our study, the quality of drinking water is further worsened in the distribution lines, possibly due to the leakage of water pipes at a point where the drainage water enters into the main drainage system [50,51]. At the school level, drainage water may be contaminated due to uncovered overhead storage tanks, underground storage tanks, and unhygienic handling of water by consumers [46,47].…”

“…In addition, the hand pumps and wells are not safe from surface runoff and flooding [24,46,49]. Industrialization and rapid urbanization have placed immense stress on water resources and discharge of wastewater into natural water resources that decreases ground and surface water quality [7,11,51]. The schools with improved water quality might have safe natural ground water source or schools with better management systems, additional support (related to WASH) from government, community, or other organizations have relatively better water quality [6,9,52].…”

“…The southern part of Sindh adjoins the seacoast where drinking water quality deteriorates ( Figure 5) due to the dumping of urban and industrial waste. This area also has limited freshwater resources [50,51].…”

“…Therefore, it can be inferred that the precautionary measures taken by the concerned authorities in the country to protect water quality have been inadequate. Furthermore, the industrial, domestic, and agricultural waste along with the climatic changes are also major threats to the drinking water quality in Pakistan [50,51].…”

Water, sanitation and hygiene: A leading cause of viral transmission in Pakistan?

“…These water-borne diseases lead to the death of nearly 94,000 people every year where 53,000, nearly 56.4%, of them are children under the age of 5 [ 4 ]. A team of researchers estimated the risk of hepatitis A infection transmission through water sources using a quantitative microbial risk assessment (QMRA) model across primary schools in Sindh, Pakistan [ 5 ]. The QMRA model was utilized to identify the risks of HAV using indicators such as fecal coliforms, where the dose-response model was employed to calculate likely infection [ 5 ].…”