Wolbachia-Aedes aegypti mosquitoes are pictured at the National Environmental Agency's mosquito production facility in Singapore August 19, 2020. Picture taken August 19, 2020.     REUTERS/Edgar Su
CNN  — 

Health officials in two states are warning people to take precautions against mosquito bites because of the presence of Eastern equine encephalitis virus, which spreads through the bite of infected mosquitoes.

Two cases have been reported in people in Alabama, with one fatality; the virus has also been found in horses and mosquitoes in New York, but no human cases have been reported there.

The Alabama cases were reported in Baldwin County “in the past few weeks,” the state’s Department of Public Health said in a news release Monday.

In New York, the virus has been found in horses in St. Lawrence and Franklin counties and in mosquitoes in Onondaga County, the State Department of Health said in a Tuesday release.

Only a few cases of Eastern equine encephalitis are reported in people in the US each year, usually in Eastern or Gulf Coast states, according to the US Centers for Disease Control and Prevention. However, it can cause very serious illness. “Approximately 30% of people with EEE die and many survivors have ongoing neurologic problems,” the CDC notes.

There are no vaccines against the virus and no specific medications to treat it.

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“People of all ages are susceptible to infection, but people over 50 and younger than 15 are at greatest risk of acquiring the virus,” the New York health department says. “While most people bitten by an infected mosquito will not develop any symptoms, severe cases begin with the sudden onset of headache, high fever, chills and vomiting. The illness may then progress into disorientation, seizures, encephalitis and coma.”

The best way to prevent infection is to avoid mosquito bites. The CDC recommends using insect repellents with ingredients such as DEET, picaridin or oil of lemon eucalyptus. When outdoors, wear long-sleeved shirts and long pants. Clothing may also be treated with 0.5% permethrin to kill or repel mosquitoes. Check your property for standing water where mosquitoes can lay their eggs.