Resistance of hepatitis A virus in mussels subjected to different domestic cookings.

Hepatitis A is a worldwide infectious disease. Shellfish consumption has always been one of the major risk factors for hepatitis A infection, especially when these products are eaten raw or slightly cooked. Moreover, the cooking does not always guarantee the harmlessness of shellfish. The aim of the present study was to evaluate the hepatitis A virus (HAV) resistance in experimentally contaminated mussels, subjected to domestic cooking. Three different domestic preparations (mussel hors-d'oevre, mussel au gratin, mussels with tomato sauce) were performed according to the traditional Italian cookery using different time and temperature conditions. To detect HAV-RNA, RT-nested-PCR was used; the presence of the infectious virus in the positive samples was confirmed by an integrated cell culture-RT-PCR method. The infectious virus was completely inactivated only in "mussels in tomato sauce", while it was still present, even if not quantitatively determinable, in the other preparations. The study confirmed that some factors can influence the HAV sensitivity to thermal inactivation preventing a complete decontamination of the product.