Viruses in Imported Frozen Scallops – April 1, 2020 to March 31, 2022

The survey was conducted to generate baseline information on the safety of imported frozen scallops sold at retail in Canada. Frozen scallops are a popular seafood among Canadians^{Footnote 2} and can be consumed in a variety of ways. They are often eaten after grilling, pan-searing, baking, frying or sautéing or sometimes eaten raw in scallop sushi, sashimi, scallop ceviche or cold smoked. Unfortunately frozen scallops have been associated with recalls^{Footnote 3}, ^{Footnote 4} and food-borne illnesses outbreaks^{Footnote 5}.

Scallops can be contaminated with viruses through contact with human waste at any step in the food supply chain such as during growth, harvest, post-harvest handling, processing, packaging, distribution, and/or at retail. Unlike bacteria, viruses are unable to grow on foods, however they can remain viable for extended periods of time and may cause illness if ingested. Therefore, the presence of viruses on scallops is of concern as they are commonly consumed by Canadians and may be consumed with minimal or no further preparation.

The survey was conducted over a 2-year period from April 1, 2020 to March 31, 2022.

Samples were collected from national retail chains and local/regional grocery stores located in the following 11 major cities across Canada:

• Halifax
• Moncton
• Quebec City
• Montreal
• Toronto
• Ottawa
• Vancouver
• Victoria
• Calgary
• Saskatoon
• Winnipeg

The planned number of samples to be collected from each city was based on the population of the province in which the city was located relative to the total population of Canada.

A total of 229 imported pre-packaged frozen scallop samples were collected. A sample consisted of a single or multiple consumer sized packages of the same lot weighing at least 300g.

All 229 samples were tested for the presence of HAV and NoV GI, GII.

Samples were analyzed using methods that detect the presence of ribonucleic acid (RNA) of HAV and NoV GI, GII.

There are currently no Canadian standards regarding the presence of viruses in frozen scallops. As the analytical methods used in this survey can only determine the presence or absence of viral RNA, they are unable to discriminate between living (infectious) and dead (non-infectious) viruses. Therefore, the detection of viral RNA was assessed as "investigative" and required further consideration to determine appropriate follow-up actions.

HAV and NoV GI, GII were not found in any samples (table 2).

Survey results are also presented by country of origin (table 3).

A 2001 study^{Footnote 6} conducted in Spain tested 17 samples (representing a total import volume of approximately 300 tons) of bivalve mollusks imported from South America for HAV, including 5 samples of scallops. HAV RNA was detected in 1 of the 5 scallop samples whereas no HAV RNA was detected in samples tested under the present study. Differing findings between studies may be attributable to differences in product type tested, methodology, study design, etc.

Overall, our survey results indicate that imported frozen scallops sold in Canada are generally safe for consumption. However, as with all foods, and especially with those that may be consumed with minimal or no further preparation, good hygienic practices are recommended for producers, retailers and consumers.

All results are used to:

• inform risk management decisions
• support program design and re-design
• develop laboratory methods

Yes. The data will be accessible on the Open Government Portal.