Since November of 2015, there have been 44 bloodstream infections caused by Elizabethkingia anophelis bacteria reported to the Wisconsin Department of Health Services (DHS), Division of Public Health (DPH). Of the 44, 18 have died. Case patients reside in Columbia, Dane, Dodge, Fond du Lac, Jefferson, Milwaukee, Ozaukee, Racine, Sauk, Washington and Waukesha counties.
These laboratory-confirmed illnesses were reported to DHS between November 1, 2015 and March 2, 2016. Because this investigation is ongoing, case counts may change as additional illnesses are identified and more cases are confirmed.
Most of the people sickened in this outbreak are over the age of 65, and all are patients with a history of at least one underlying serious illness.
At this time, the source of these infections is unknown and DHS is working to contain this outbreak.
Elizabethkingia are bacteria that rarely cause illness; however, when illnesses occur, the mortality rate is high. In one study, ” death occurred in 33% of patients, predominantly in patients with pneumonia” (1). To date, the mortality rate is higher in this outbreak, about 40%.
Signs and symptoms of illness associated with exposure to the bacteria can include fever, shortness of breath, chills or cellulitis (skin rash). Laboratory testing needs to be done to confirm illness from Elizabethkingia.
According to DHS, health providers should consider the “index of suspicion” for Elizabethkingia infections high among patients with multiple co-morbid conditions, particularly cancer, diabetes mellitus, chronic renal disease (particularly end-stage kidney failure on dialysis), alcohol dependence, alcoholic cirrhosis (late-stage scarring of the liver), immune compromising conditions or immunosuppressive treatment.
Elizabethkingia are multidrug-resistant bacteria; however, there may be some drugs that can be effectively used for treatment of patients sickened in this outbreak. DHS has conducted antimicrobial susceptibility testing (AST) at clinical microbiology laboratories in Wisconsin of at least 6 isolates of Elizabethkingia obtained from outbreak victims. DHS found that most of the isolates tested are susceptible to trimethoprim/sulfamethoxazole, flouroquinolones, and piperacillin/tazobactam. According to DHS, treatment of patients involved in this outbreak should be guided with AST, and health providers should be aware that the medical literature suggests “combination treatment with these agents may be more effective than monotherapy,and the addition of vancomycin may be beneficial in some cases.”
Pereira, Graziella H., et al. “Nosocomial infections caused by Elizabethkingia meningoseptica: an emergent pathogen.” The Brazilian Journal of Infectious Diseases 17.5 (2013): 606-609.