The British Columbia Centre for Disease Control (BCCDC) is warning the public following a spike in acute gastrointestinal illness associated with the consumption of oysters.
Since early December 2016, over 70 cases of oyster-related illness have been reported to BC health authorities. Illnesses have been reported to Island Health, Vancouver Coastal Health, Fraser Health and First Nations Health Authority. The outbreak is ongoing and more cases are expected.
People who have been ill have reported eating raw oysters or lightly-cooked oysters in restaurants or prepared at home.
“Testing in several of the cases confirmed the presence of norovirus, and we suspect norovirus in the others,” said Dr. Eleni Galanis, epidemiologist at the BCCDC. “In order to kill norovirus and other bugs, people need to cook oysters thoroughly, to an internal temperature of 90 degrees Celsius for 90 seconds.”
Dr. Galanis says oysters can make people sick at any time during the year. While raw oyster consumption during the summer months is linked to an increased risk of illness from “Vibrio” (Vibrio parahaemolyticus), other microorganisms like norovirus can be present all year.
The investigation is ongoing.
Norovirus is a highly contagious viral illness that often goes by other names, such as viral gastroenteritis, stomach flu, and food poisoning.
The symptoms include nausea,vomiting, diarrhea, and some stomach cramping. Sometimes people additionally have a low-grade fever,chills,headache, muscle aches, and a general sense of tiredness. The illness often begins suddenly, and the infected person may feel very sick. In most people, the illness is self-limiting with symptoms lasting for about 1 or 2 days.
In general, children experience more vomiting than adults do.
Norovirus is spread person to person particularly in crowded, closed places. Norovirus is typically spread through contaminated food and water, touching surfaces or objects contaminated with norovirus and then putting your hand or fingers in your mouth and close contact with someone who is vomiting or has diarrhea.