This paper published in the journal Tropical Medicine and International Health describes the findings of the study conducted by the National Institute of Virology, Pune, that aimed at evaluating the performance of domestic water purification units with respect to contaminating enteric viruses.
Consumption of microbiologically contaminated water can lead to a range of bacterial diseases such as amoebiasis, cryptosporidiosis, giardiasis, leptospirosis, legionellosis, campylobacteriosis, cholera, typhoid, paratyphoid, gastroenteritis and viral infections such as hepatitis A, hepatitis E, diarrhoea as well as several enteroviral diseases.
Hepatitis E virus (HEV) infection by the faecal ⁄ oral route is an important cause of epidemic and sporadic acute viral hepatitis among Indian adults. In India, the average incidence of viral hepatitis is 12 cases per 100 000 people, while in urban communities, incidence of viral hepatitis might be around 100 per 100, 000 people. HEV is responsible for a substantial proportion of sporadic fulminant cases of hepatitis among Indian men and nonpregnant women, and high mortality among pregnant women during epidemics.
The evaluation of drinking water supply in Indian cities shows increasing evidence of microbial contamination. Various types of water purification units are currently used in India for treatment of water at the household level. However, no standards are currently available for the virological evaluation of water purification units in India.
This paper describes the findings of a study that aimed at the development of a sensitive method for virological evaluation of domestic water purifiers using HEV as a model virus and evaluated various domestic water purification systems. Eight domestic water purification systems widely used in India were evaluated using hepatitis E virus (HEV) as a model virus.
The results indicated that six of eight units tested (one unit ⁄ type) did not conform to United States Environmental Protection Agency (USEPA) standards and were thus inadequate to meet water purification outcomes. However, the paper argues that the minimum standards established by USEPA were not designed for developing countries, where the microbiological quality of public water supply may not be as good as in developed countries.
The paper argues that India and other developing countries thus need to formulate their own standards and ensure strict adherence by all those concerned, which will help both manufacturers and consumers to be quality conscious with respect to drinking water.
Such an exercise will ensure availability of quality-assured domestic water purification units to the community, help manufacturers to improve the performance of such products and most importantly, help consumers by reducing the burden of water-borne infections, argues the paper.