Shellfish harvesting: Higher concentration of bacteria in warm ocean may be causing rise in illness, BCCDC warns

Mussels are seen in this undated image. (Shutterstock)

Vancouver -

Warm ocean waters may be behind multiple recent reports in B.C. of an illness that causes diarrhea, vomiting and fever.

The B.C. Centre for Disease Control said in a statement Wednesday that it's received five reports of vibrio illness, caused by the bacteria with the same name.

The bacteria can become concentrated in shellfish when the ocean is warmer in the summer, prompting health officials to issue a warning about safe harvesting and consumption of clams, mussels and other shellfish.

Illness from the bacteria can cause abdominal cramping, nausea, vomiting, fever, diarrhea and chills. The symptoms typically last for about three days.

To avoid sickness, the BCCDC says those harvesting shellfish should do so when the tide is going out. After harvesting, shellfish should be placed in a chilled cooler to prevent bacteria from growing. Harvesters should also check out the shellfish status map before digging and collecting. 

Anyone preparing shellfish should make sure it's fully cooked by letting its temperature get to 90 C for 90 seconds. The BCCDC also says crab shouldn't be cooked whole, but should be split and have guts removed before boiling to remove any toxins.

"Keep cooking areas clean," the BCCDC's warning says. "Separate raw and cooked seafood to prevent cross-contamination and clean and sanitize knives and cutting boards. Wash hands frequently."

It's not uncommon for B.C. to record a rise in vibrio illness during the summer months. In previous years, dozens of cases have been reported. In 2015, for example, 62 people became ill from vibrio bacteria.