Differential accumulation and depuration of human enteric viruses by mussels

Abstract

The tissue distribution of adenovirus 40 (ADV) and human rotavirus, serotype 3 (HRV) was determined after feeding the common mussel (Mytilus spp.) with high levels of clay-associated virus. At different time intervals, individual tissues were carefully dissected and assayed for infectivity. Viruses were detected in contaminated mussels after 1-hour contact, and maximum levels were observed after 6 hours. Most infectious viruses were located in the gills and in the digestive tract. Decreasing virus numbers were found in the mantle lobes. Mussels contaminated with poliovirus 1 (PV), hepatitis A virus, strain HM-175 (HAV), ADV, HRV, and bacteriophages of Bacteroides fragilis (B40-8) were depurated in 50-1 tanks with a continuous flow of ozonated marine water. After 96 hours, HAV and HRV suffered less than 2 Log10 titre reduction (LTR), while ADV showed a 2.7 LTR. PV showed a 3 LTR after 48 hours and became undetectable thereafter. Bacteriophage B40-8 suffered less than 2 LTR after 96 hours, suggesting that it could be an appropriate indicator of the efficiency of virus elimination during shellfish depuration.