More than 1,000 Americans have contracted salmonella as part of an outbreak linked to onions, according to the Centers for Disease Control (CDC).

Retailers including Walmart, Kroger and Food Lion have issued national recalls after salmonella was linked to onions supplied by Thomson International, Inc.

Americans have been sickened in at least 47 states, according to the CDC, leading to 136 hospitalizations. No deaths have been confirmed as part of the outbreak.

"If you can’t tell where your onions are from, don’t eat them or any food made with them. Throw them away,” the CDC said.

On. Aug. 1, California-based Thomson International, Inc. announced a voluntary recall for its red, yellow, white and sweet yellow onions shipped after May 1, upon finding they might have been contaminated with salmonella.

The CDC is urging people to throw away onions that are under recall, including any food that might have been made with them.

In Canada, there have been a total of 457 confirmed cases of salmonella linked to the imported onions.