Seventeen people in the United States have died in the past few months of an unusual illness—and the geographic distribution of the cases makes no logical sense.
As of Wednesday, Wisconsin has seen 54 cases, spread across 12 counties, of a rare disease caused by Elizabethkingia, a bacteria commonly found in water and soils. The disease doesn’t take hold that frequently in humans; there are about a half dozen cases in every state each year, and they usually occur in people with immune weak systems. And this particular strain, Elizabethkingia anophelis, typically occurs in much smaller outbreaks affecting fewer than 10 people. So this most recent outbreak is cause for concern—especially given that no one seems able to track down its source.
Here’s Sarah Zhang, reporting for Wired:
At first, the CDC suspected the tap water. Just this January, the CDC’s emerging diseases journal published a report about a nearly two-year long Elizabethkingia outbreak in a London critical care unit that ended up originating with contaminated taps in hospital sinks. But the tap water in Wisconsin turned up negative for the bacteria.
Adding to the mystery, this outbreak doesn’t match the pattern of other infections, which appeared in clusters in the same facility. Most of Wisconsin patients were elderly; some lived in nursing homes and others had gone to the hospital, but they lived across 12 different counties. At the same time, the genetic signature of the bacteria points to a single source. The infection seems, to use the language of epidemiology, to be community-acquired. This makes tracing a source more difficult: The CDC’s officials can’t just order up medical records from a single hospital and test the area exhaustively.
Elizabethkingia, if it infects a person at all, blights the blood stream—but in some of the Wisconsin cases, people have reacted with skin infections. Another person experienced a joint infection, as well. Health officials are now on the lookout for other possible origins: lotions, wipes, even water on produce in grocery stores.
Unfortunately, Elizabethkingia anophelis tends to have natural defenses against many antibiotics that could treat the disease. But it isn’t immune to all of them. “Because of that, we’ve done early tests on the particular strain causing the outbreak,” Michael Bell, deputy director for the Division of Healthcare Quality Promotion at the Centers for Disease Control and Prevention in Atlanta, told Wisconsin Public Television’s “Here and Now.” Watch WPT’s interview with Bell below to find out how the CDC is approaching this emerging problem.