The unusual, and as yet unexplained cluster of Elizabethkingia cases in Wisconsin (and 1 in Michigan) that we've been following for the past 6 weeks (see chart above) took another unexpected turn yesterday when Illinois reported a case of their own.
Elizabethkingia is a ubiquitous, multi-drug resistant, gram negative aerobic bacillus that on very rare occasions causes opportunistic infections in (mostly immunocompromised) humans.
Previous outbreaks have been relatively small, and have almost always been associated with nosocomial transmission. It is rare enough that a state the size of Wisconsin might only see 1 or 2 cases in a normal year.
Despite intensive investigation by Wisconsin and Michigan health officials, and the CDC, the cause of this unprecedented outbreak remains unknown.
Yesterday, the Illlinois State Department of Health issued the following statement on the discovery of their own case.
Elizabethkingia cases found in Wisconsin, Michigan, Illinois
SPRINGFIELD – The Illinois Department of Public Health (IDPH) is reporting that tests from an Illinois resident match those from a Wisconsin outbreak of Elizabethkingia anophelis. The Centers for Disease Control and Prevention (CDC), the Wisconsin Department of Health Services, and the Michigan Department of Health and Human Services have been investigating an outbreak of infections caused by a bacteria called Elizabethkingia anophelis, which is usually found in the environment.
“Illinois is working closely with the CDC and Wisconsin and Michigan health officials to investigate this outbreak and develop ways to prevent additional infections,” said IDPH Director Nirav D. Shah, M.D., J.D. “IDPH will continue to coordinate with hospitals and health care providers to quickly identify and report cases of Elizabethkingia.”
In early February, and again in March, IDPH sent alerts to hospitals requesting they report all cases of Elizabethkingia and save any specimens for possible testing at public health laboratories.
To date, Wisconsin is reporting 57 confirmed cases, including 18 deaths; Michigan is reporting one confirmed case, including one death; and Illinois is reporting one confirmed case, including one death.
The majority of the infections identified to date have been bloodstream infections, but some patients have had Elizabethkingia isolated from other sites, such as their respiratory systems or joints. The majority of the patients who have had Elizabethkingia infections as part of this outbreak are over age 65, and all have had underlying health conditions. It has not yet been determined whether the deaths associated with this outbreak were caused by the bacterial infection, the patients’ underlying health conditions, or both.
Although Elizabethkingia is a common organism in the environment (water and soil), it rarely causes infections. Health officials are testing samples from a variety of potential sources, including health care products, water sources, and the environment. To date, none of these has been identified as the source of the bacteria.
More information about Elizabethkingia can be found on the CDC website.