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EPA Grants Extension of Experimental Use Permit for ‘Wolbachia Mosquito’

For Release: September 21, 2016

EPA has approved and expanded an existing experimental use permit (EUP) for Wolbachia pipientis-infected Aedes aegypti mosquitoes. Wolbachia are naturally occurring bacteria commonly found in most insect species, but not in the Aedes aegypti. The EUP was issued to the University of Kentucky’s Department of Entomology (UKDE) in October 2015 for limited testing in Fresno County, California. The updated EUP also authorizes testing to evaluate the Wolbachia pipientis bacteria’s effectiveness in suppressing and eliminating Aedes aegypti mosquitoes at particular sites in Fresno and Orange County in California and Monroe County in Florida.

Wolbachia pipientis are bacteria that generally do not occur in wild populations of Aedes aegypti. This strain of Wolbachia is extracted from Aedes albopictus embryos and microinjected into Aedes aegypti embryos.  These male Aedes aegypti mosquitoes are shipped to testing sites where they are released and mate with wild-type Aedes aegypti females that do not carry Wolbachia. After mating, the bacteria prevents the new embryos from developing properly so the mosquitoes cannot successfully reproduce.  As the Aedes aegypti mosquitoes are known to carry numerous diseases, including the Zika virus, it is important to note that information gathered under this EUP may lead to a new tool to help control mosquitoes that carry diseases. 

In February 2016, EPA published a Notice of Receipt of the university’s application and took public comment. EPA concluded that the experimental work initially approved for the EUP in 2015 presented minimal risks to non-target organisms and the environment. The additional sites and extended time do not raise any new risk concerns for EPA. 

Documents related to this EUP, including scientific assessments, are available in Docket EPA-HQ-OPP-2015-0374 on  (EPA has issued, amended, and/or extended other experimental use permits using this same technology in another mosquito species, Aedes polynesiensis or Aedes albopictus in 2012, 2013, and 2014. Information on those EUPs is available in Docket EPA-HQ-OPP-2012-0181 and Docket  EPA-HQ-OPP-2013-0254 at