A rare disease stemming from bacteria common in water and dirt has killed 17 people in Wisconsin since November 2015, and health experts are grappling for answers. The bacteria, Elizabethkingia, is relatively common, but it doesn’t usually make humans sick, let alone kill them. Yet, health officials report 54 documented cases of illness spread across 12 counties in the state of Wisconsin as of last week. The confusing thing is that outbreaks of this strain are typically quite small and concentrated—10 or fewer patients within close proximity—and epidemiologists have yet to trace the source of this particular outbreak.

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Elizabethkingia anophelis is wreaking havoc in Wisconsin and causing health officials to scratch their heads. Hunting down the source of the bacterium has been difficult. A similar outbreak in London prompted investigators to look into tap water, but tests came back negative. Although most of the patients are elderly with other underlying health conditions, they have little else in common that might lead officials to a specific source of the bacteria. Some live in nursing homes, while others had been to a hospital, but the cases are scattered across a relatively large area, and not concentrated to one or neighboring communities, which is typically how outbreaks related to Elizabethkingia behave.

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The symptoms people exhibit are also different with this strain, causing further confusion. While Elizabethkingia typically impacts the blood, some patients are turning up with skin infections, and one patient presented with a joint infection. The bacteria can be resistant to some antibiotics, but early testing is being used to identify which drugs can be used to treat the infection. The Wisconsin Department of Health has issued a warning urging anyone with symptoms to see a doctor, as the disease can only be confirmed through laboratory testing. The infection is not transmittable from patient to patient.


Images via CDC Special Bacteriology Reference Lab and Wikipedia