Officials have connected a frozen fruit product to an outbreak of Hepatitis A.

The product in question is a medley of frozen fruit, specifically organic berries and cherries, made by Nature’s Touch. According to Food Safety News, health officials are concerned with 1.5 kg, or 3.3 lb bags that have Best Before dates on or prior to March 15, 2018.

Nature’s Touch Organic Berry Cherry Blend had been sold at Costco locations in Canada, though it’s uncertain whether it was distributed to any other retailers or to the U.S. Costco only posted a notice for the Class I recall on its Canadian website, and not on its U.S. website. “There is an ongoing investigation as to whether any of the ingredients in this blend could have been added to any products destined for the U.S.,” a Nature’s Touch spokesperson told Fortune. “We have very little distribution, if any, of common ingredients under investigation, but we obviously want to be absolutely certain.” According to the Public Health Agency of Canada’s count, there have been 12 reported cases of Hepatitis A in Canada, with three hospitalizations.

“This recall was triggered by findings of the [Canadian Food Inspection Agency] during the investigation of a foodborne illness outbreak,” the CFIA wrote in its recall notice. People first became sick in February and March, and some of those who fell ill reported eating the product in question. Officials warn consumers to return products to the store or throw them away, adding that “food contaminated with Hepatitis A virus may not look or smell spoiled.”

Symptoms tend to begin between 15 and 50 days after being exposed to the virus, and generally last a week or two. Symptoms include fever, loss of appetite, stomach cramps, jaundice, fatigue, and in some cases, inflammation of the liver.

Costco (COST) could not immediately be reached for comment.