RESUMO
Infection with the hepatitis E virus (HEV) can cause acute and chronic hepatitis in humans. The zoonotic HEV genotype 3 is mainly transmitted by consumption of raw and fermented meat products prepared from infected pigs or wild boars. Lowering of pH during fermentation is one of the microbiological hurdles considered to inhibit growth of certain pathogens. However, no data are currently available on pH stability of HEV. As a reliable and reproducible measurement of HEV infectivity in meat products is not established so far, the stability of the cell culture-adapted HEV genotype 3 strain 47832c was analyzed here in phosphate-buffered saline (PBS) at different pH values. Only a minimal decrease of infectivity (up to 0.6 log10 focus forming units) was found after treatment at pHâ¯2 to 9 for 3â¯h at room temperature. At pHâ¯10, a decrease of about 3 log10 was evident, whereas no remaining virus (>3.5 log10 decrease) was detected at pHâ¯1. The conditions usually achieved during curing of raw sausages were simulated using D/L-lactic acid added to PBS resulting in pHâ¯4.5 to 6.5. After incubation at 4⯰C for 7â¯days at these conditions, no significant differences as compared to a standard PBS solution at pHâ¯7.7 were evident. At room temperature, a 0.8 log10 decrease was found at pHâ¯4.7 after 7â¯days incubation compared to pHâ¯7.7, but less at the other pH values. In conclusion, only minimal inactivating effects were found at pH conditions commonly occurring during food processing. Therefore, remaining infectious virus might be present in fermented meat products if HEV-contaminated starting material was used. Additional effects of other factors like high salt concentrations and low aw values should be investigated in future studies.