The Indiana Department of Health announced Friday plans to conduct the aerial application of pesticide to control Eastern equine encephalitis (EEE) virus in northern Indiana.
The state Department of Health has reported a lab-confirmed case of EEE virus disease in a LaPorte County resident. The state Board of Animal Health (BOAH) has recorded probable EEE cases in two horses in LaGrange County, one horse in LaPorte County and one horse in Kosciusko County. BOAH suspects EEE in three additional horses in LaGrange County.
Health officials plan targeted mosquito control to help protect residents from EEE beginning Tuesday evening and continuing Wednesday if needed, as weather permits.
“Although it’s rare, Eastern equine encephalitis can cause serious illness and is fatal in about a third of people who contract this disease,” said State Health Commissioner Kris Box,
M.D., FACOG. “We are taking this step to protect Hoosiers in the affected areas, but I urge everyone to take precautions to guard against mosquito bites and to eliminate mosquito breeding grounds until we have the first hard freeze.”
Mosquitoes that carry EEE virus have a flight range of up to five miles. As a result, the affected area includes approximately 375,000 acres in portions of Elkhart, Kosciusko, LaGrange, LaPorte, Marshall and Noble counties.
Mosquito control professionals will apply an approved pesticide, Dibrom, as an ultra-low volume (ULV) spray. ULV sprayers dispense very fine aerosol droplets that stay suspended in the air and kill adult mosquitoes on contact. Dibrom has been registered by the U.S. Environmental Protection Agency (EPA) since 1959 for use in the United States.
People who wish to minimize exposure may choose to stay indoors for several hours, beginning at dusk on the treatment dates. People may also choose to bring animals indoors and cover their ornamental fishponds prior to the spraying. Evening application of Dibrom is not expected to be harmful to bees, but beekeepers may choose to cover their hives overnight and prevent bees from exiting during the application as a precaution.
In 2019, northern Indiana experienced a significant outbreak of EEE virus activity, resulting in 14 horse cases, one fatal human case and one positive mosquito sample. The Indiana Department of Health also conducted spraying during the 2019 outbreak.