A guest reported feeling sick after eating raw oysters. What pathogen probably caused the illness?

The most likely pathogen that causes illness from eating raw oysters is Norovirus. This virus is often associated with shellfish, especially mollusks like oysters that are harvested from contaminated waters. Oysters can bioaccumulate pathogens from their environment, and when consumed raw or undercooked, they can lead to gastroenteritis, presenting symptoms like nausea, vomiting, and diarrhea.

Raw oysters can be particularly risky, as they are frequently harvested from waters that may harbor this virus, especially during outbreaks. Conditions such as poor sanitation and contamination of water supplies are contributing factors.

Other pathogens, while linked to foodborne illness, are less common specifically in relation to raw oysters. Salmonella and Escherichia coli are typically associated with undercooked meats, and Listeria usually relates to ready-to-eat foods or dairy products. Therefore, when considering the association of pathogens with raw oysters, Norovirus stands out as the primary concern.