A Colorado man has filed a lawsuit against McDonald's over an E coli outbreak linked to Quarter Pounder burgers that has killed one person and made nearly 50 others sick.

The lawsuit, which was filed in Circuit Court in Cook County, Illinois, on Wednesday, local time, alleges that Eric Stelly ate food from a Greeley, Colorado, McDonald's on October 4 and tested positive for E coli a few days later. 

Colorado health officials later told Mr Stelly that his E coli was connected to the McDonald's outbreak, the lawsuit said. 

Mr Stelly lives in Greeley, but sued McDonald's in Chicago, where the company is based.

The lawsuit, which seeks more than $US50,000 ($75,392) in damages, claims McDonald's was negligent in its handling and care of the food. 

Shares pared gains after news of the lawsuit and were last up 0.5 per cent.

Representatives of McDonald's did not immediately respond to a request for comment.

On Wednesday, McDonald's USA president Joe Erlinger said the fast-food chain needed to rebuild trust with the public after it pulled the item off its menu at a fifth of its 14,000 restaurants in the US.

The outbreak has sickened people across the US West and Midwest, with one dead and 10 hospitalised due to serious complications, according to the US Centers for Disease Control and Prevention (CDC).

Ron Simon, an attorney representing Mr Stelly, said he was representing another 15 people who were affected by the outbreak.

The CDC and McDonald's are scrutinising the company's supplies of slivered onions and beef patties as they try to determine the cause of the outbreak, the company said. 

On Thursday, officials with the restaurant chain said a California-based produce company was where the fresh onions came from that are linked to a deadly E coli food poisoning outbreak at McDonald's.

Officials with the US Food and Drug Administration (FDA) did not confirm that the agency was investigating Taylor Farms. 

A spokesperson said on Thursday the agency was "looking at all sources" of the outbreak.

In the meantime, other national restaurant chains have temporarily stopped using fresh onions.

"As we continue to monitor the recently reported E coli outbreak, and out of an abundance of caution, we have proactively removed fresh onions from select Taco Bell, Pizza Hut and KFC restaurants," Yum Brands said in a statement.

McDonald's officials said Taylor Farms, of Salinas, California, sent onions to one distribution facility, which led the fast-food chain to remove Quarter Pounder hamburgers from restaurants in several states.

The fast-food chain didn't say which distribution facility it was.

Major wholesaler US Foods said on Thursday, that Taylor Farms had issued a recall this week for peeled, whole and diced yellow onions for potential E coli contamination.

The recalled onions came from a Taylor Farms facility in Colorado, a US Foods spokesperson said.

But the wholesaler also noted that it wasn't a McDonald's supplier and that its recall didn't include any products sold at the fast-food chain's restaurants.

Taylor Farms did not respond to AP for comment.

The US Department of Agriculture said late on Wednesday that the onions used were the likely source of the illness, though one of its state partners is testing samples of the beef for E coli.

Spokespeople for McDonald's suppliers said the restaurant chain tests their products frequently.

AP/Reuters