Low occurrence of Hepatitis A virus in water samples from an urban area of Southern Brazil.

Hepatitis A virus (HAV), a member of Picornaviridae family, is the main causative agent of acute viral hepatitis in the world, mainly in developing countries. HAV may be present in contaminated water and food and its presence is often associated to a lesser extent with socioeconomic factors and environmental quality. The main goals in the present study were to standardize a cell culture combined to a polymerase chain reaction protocol for the detection and quantification of viral viability and analyze whether the virus could be found in water samples collected in four urban streams of Sinos River watershed. Virus recovery was assayed from known virus concentrations measured in experimentally contaminated raw and ultrapure water (MilliQ®). Recovery rates ranged from 270% in raw water to 15,000% in ultrapure water. In a second step, a qPCR coupled to a previous passage in cells, demonstrated more analytical sensitivity when compared to samples assayed without a previous passage in cell cultures. HAV genome was detected in only 1 of 84 samples analyzed, pointing to a very low occurrence of HAV in water samples in the studied region. These findings are remarkable, since no more than 5% of the domestic sewage in this area is treated pointing to a low occurrence of HAV in the population living nearby during the study period.