Elizabeth Armstrong Moore

Newser staff

(NEWSER) – A mysterious blood infection is spreading in Wisconsin, and officials don't know how or why. Members of the Atlanta-based Centers for Disease Control and Prevention are now on the ground alongside state investigators hoping to find exactly what is causing the spread of the bacteria Elizabethkingia, which has so far infected 44 people, most of them older than 65, reports the Wisconsin Department of Health Services. Though these bacteria typically don't cause illness in humans, symptoms can range from fever and shortness of breath to rash and cellulitis — but in this unusual outbreak, 18 of the patients have died, reports the Chicago Tribune. "We are keeping every possibility on the table, but it does not seem to be [spread] from person to person," state health officer Karen McKeown says.

Six cases of the infection were initially recorded between Dec. 29, 2015, and Jan. 4, 2016, and when state health officials notified local partners the number grew and was found to date back to a case in November of 2015. Everyone affected already had serious underlying health conditions or compromised immune systems, and none are children. And while Elizabethkingia (named after Elizabeth King, who discovered the bacterium in 1959, reports CNN) is abundant in our environment, including water and soil, infections are rare. So far none of the possible sources the CDC has investigated, including health care products and water, have proven to be the common link. Even as they grieve, family members of the deceased are being interviewed and "providing information to help," McKeown says (Check out what this woman put on her wrist that caused a raging infection.)

This story originally appeared on Newser:

A Mysterious Outbreak in Wisconsin Has Now Infected 44 People, and 18 of Them Died

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