A person who died in Michigan tested positive for a bacteria linked to as many as 17 deaths in neighboring Wisconsin, health officials said on Thursday.
The resident was elderly and had underlying health conditions, but a blood culture revealed the presence of the Elizabethkingia bacteria, Michigan health officials said.
The Centers for Disease Control (CDC) confirmed the test, the officials said.
Michigan's health and human services department previously asked providers and laboratories to review records for Elizabethkingia in light of the outbreak in Wisconsin, which has infected at least 54 people since November, most of them elderly.
The patients who have died in Wisconsin had serious underlying conditions, according to health officials, and it remains unclear whether the bacteria caused all of the deaths.
Wisconsin and Michigan investigators are working with the CDC to determine the possible source of the bacteria, which only rarely causes illness in humans.
Officials have previously said that the CDC has eight disease detectives in Wisconsin and laboratory staff in its Atlanta headquarters working on the outbreak.
Symptoms of Elizabethkingia infection can include fever, shortness of breath, and chills or cellulitis. Confirmation of the illness requires a laboratory test.