Raleigh, N.C. — Three more North Carolinians – one each from Brunswick, Caldwell and Catawba counties – have tested positive for the same strain of Salmonella typhimurium that has sickened more than 400 people nationwide, state officials said Friday.

The Catawba County resident died in November due to a blood infection caused by Salmonella, officials said, while the other people have recovered. The state’s first identified case, in a person from Robeson County, was reported last Friday.

The federal Centers for Disease Control and Prevention reported Wednesday that that at least 453 people have been infected with Salmonella typhimurium with the same genetic fingerprint – indicating a common infection source – in 43 states. Five of those people had died.

State health officials continue to investigate the North Carolina cases and are looking at laboratory test results for other potential cases linked to the outbreak.

A likely source of the bacteria causing the infections is peanut butter sold in large containers to institutions, food service industries and private-label food companies across the country, but not directly to consumers, officials said.

Several companies have now issued voluntary recalls on peanut butter. In addition, other companies have stopped the sale and distribution of products containing peanut butter, such as peanut butter crackers. Grocery-store brands of peanut butter have not been implicated in the outbreak.

Salmonella can cause fever, diarrhea, nausea, vomiting and abdominal pain, and the illness usually lasts four to seven days. Although most people recover without treatment, severe infections may occur, particularly in young children, frail or elderly people and those with weakened immune systems.