Earlier this week, Wisconsin health officials reported on 44 cases of Elizabethkingia anophelis infections in 11 counties since Nov. 1, 2015.


What is this not-so-common human pathogen, Elizabethkingia?

A search of the literature shows that Elizabethkingia anophelis is a bacteria species in the family Flavobacteriaceae, gram negative aerobic bacillus. It is a dominant resident in the mosquito gut of the malaria vector mosquito Anopheles gambiae and also a human pathogen.

In 2013, E. anopheles was reported as a human pathogen in Central Africa and an outbreak was also seen in an intensive care unit in Singapore; in both clinical cases multidrug resistance was reported.

It has been associated with neonatal meningitis and nosocomial outbreaks; however, its transmission route remains unknown.

Maternal infection, not mosquitoes, is most likely the source of neonatal E. anophelis infections. The pathogenic and multiresistant nature of the bacteria prompts investigations of the vector potential of mosquitoes for E. anophelis transmission to humans.

The Wisconsin Department of Health offers the following information on the genera:


Elizabethkingia are opportunistic pathogens preferentially causing illness among immune compromised individuals or patients with underlying medical conditions, and infection is associated with high mortality. Therefore, early detection and treatment with an effective antibiotic regimen is important to increase the probability of good outcomes.

The index of suspicion for Elizabethkingia infections should be high among patients with multiple co-morbid conditions, particularly malignancy, diabetes mellitus, chronic renal disease or end-stage renal disease on dialysis, alcohol dependence, alcoholic cirrhosis, immune compromising conditions or immunosuppressive treatment.

Although Elizabethkingia are multidrug-resistant bacteria, antimicrobial susceptibility testing (AST) conducted at clinical microbiology laboratories in Wisconsin of at least 6 isolates of Elizabethkingia  with the outbreak PFGE pattern demonstrated most of the isolates tested are susceptible to trimethoprim/sulfamethoxazole, flouroquinolones, and piperacillin/tazobactam. 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. Whenever possible, treatment should be guided with AST.