Heat inactivation of hepatitis A virus and a norovirus surrogate in soft-shell clams (Mya arenaria).
The effectiveness of different thermal treatments for inactivating two viruses in clams was evaluated. Soft-shell clam digestive glands experimentally contaminated with hepatitis A virus (HAV) or murine norovirus (MNV) were heated for 90, 180, or 300 seconds at 85°C or 90°C in glass vials or plastic bags with 200 g of soft-shell clam meat. Inactivation was measured by plaque assay and real-time reverse-transcription (RT)-polymerase chain reaction assay. Measured inactivation was similar using both assays. The 90°C for 90 seconds treatment reduced MNV-1 titer by 3.33 log cycles and HAV by 2.66 log cycles. At 90°C for 180 seconds, both MNV-1 and HAV were completely inactivated (titer reduced by 5.47 log cycles) in glass vials. In the presence of clam meat as well, HAV inactivation was complete at 90°C for 180 seconds. In general, HAV was more resistant to heat treatment than MNV-1, suggesting that it would require a more severe treatment than human norovirus for inactivation in soft-shell clams. The results of the present study should contribute to the development of strategies for controlling the spread of enteric viral illness via shellfish.
Institut des Nutraceutiques et des Aliments Fonctionnels, Université Laval, Québec, Québec, Canada.
Halimatou
H
Sow
Michel
M
Desbiens
Rocio
R
Morales-Rayas
Solange E
SE
Ngazoa
Julie
J
Jean
D000818:Animals; D004203:Disinfection / Q000379:methods; D005506:Food Contamination / Q000032:analysis; D030041:Hepatitis A virus / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D006358:Hot Temperature; D049892:Mya / Q000821:virology*; D029322:Norovirus / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D012367:RNA, Viral / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012758:Shellfish / Q000821:virology*; D010948:Viral Plaque Assay; D038301:Virus Inactivation
D012367:RNA, Viral