The recent hot weather on the West Coast may be great news for outdoor enthusiasts, but health agencies warn it’s responsible for an unprecedented number of shellfish-related illnesses.

The BC Centre for Disease Control says 35 people have fallen ill in the past two months from vibrio parahaemolyticus, a bacteria that’s naturally-occurring in shellfish like oysters, clams, mussels and scallops.

The BCCDC says the bacteria spikes during the summer as water temperatures rise.

“The unseasonably high temperatures this summer may be contributing to the early and large increase in illnesses being reported,” a bulletin from the agency said.

The majority of cases are linked to eating raw B.C. oysters served in restaurants, though some incidents are linked to oysters either self-harvested or purchased from retail outlets.

The illness occurs when contaminated shellfish is eaten raw or undercooked. The bacteria can also multiply if shellfish isn’t kept cold after harvesting.

Most people who become sick suffer three to seven days of diarrhea, nausea, vomiting and fever. Headaches and bloody stools can occur as well.

The health agency says consumers can decrease their risk of illness by only eating cooked shellfish, because heating will destroy the bacteria.