Senior investigator Dr. Wilina W. L. Lim notes outbreaks of gastric illness caused by norovirus are often linked to eating tainted oysters, making contamination fairly widespread.
The team found 10.5 percent of 507 samples of oysters from 11 countries tested upon arrival came up positive for norovirus genetic material. Oysters from six countries were contaminated, while those from the remaining five countries were not. They did not specify which countries fall into these groups.
Screening for norovirus was conducted after 13 oyster-related gastroenteritis outbreaks in hotels or restaurants in Hong Kong. Norovirus sequences were found in at least one oyster in six outbreaks.
