Ontario's top doctor is urging anyone who may have eaten potentially contaminated berries purchased at Costco to get a hepatitis A vaccination immediately.

Dr. David Williams, the province's chief medical officer of health, issued a news release Tuesday saying anyone who may have consumed the berries should act as soon as possible.

"To date, 13 cases of hepatitis A linked to this recall have been reported in Canada, 10 of which have been reported in Ontario," Williams said in his statement.

The Canadian Food Inspection Agency recalled 1.5kg bags of Nature's Touch Organic Cherry Berry Blend with best-before dates up to and including March 15, 2018. The bags have a UPC code of 8 73668 00179 1.

The potentially contaminated berries were sold at Costco warehouse locations in Ontario, as well as Quebec, New Brunswick, Nova Scotia and Newfoundland and Labrador.

Williams said anyone who had previously been fully vaccinated against hepatitis A don't need to get another shot.

Costco locations are offering free hepatitis A vaccine clinics for anyone affected by the recall, Williams said.