The DeKalb County health department announced Tuesday that a mosquito tested positive for the deadly Eastern equine encephalitis virus.

Humans rarely become infected and cases are uncommon in Georgia, said Ryan Cira, the environmental health director for the DeKalb Board of Health. However, 33 percent of people who are infected with EEE die and others experience significant brain damage.

“It’s a very serious illness if it is to infect a person,” he said.

Mosquito species known to carry EEE are found mostly in coastal, swampy areas, Cira said.

Now that the virus has been identified in DeKalb, public health officials are reminding residents to stay vigilant to prevent the transmission of a disease with no known treatments. This includes removing standing water, reducing the amount of exposed skin when outdoors and wearing insect repellent with DEET.

One human case of West Nile virus has been reported in DeKalb this year. Statewide, there have been at least seven human cases, one of which was fatal.