BERKLEY HEIGHTS, New Jersey (WABC) -- The New Jersey Department of Health is encouraging residents to take steps to protect themselves from all mosquito-borne diseases after 2 more human cases of Eastern Equine Encephalitis were confirmed in the state.
The new cases were confirmed in Union and Atlantic counties on Thursday. The Department confirmed the first human case of Eastern Equine Encephalitis in August.
Earlier this week, eastern equine encephalitis (EEE) was found in a mosquito pool in Berkley Heights, New Jersey, authorities said.
The mosquito pool was found in the Emerson Lane area of Union County near the border with Warren.
Union County officials said they would continue to aggressively spray in Berkley Heights Township.
To date, Eastern Equine Encephalitis has been detected in 65 mosquito samples in 13 New Jersey counties.
Most persons infected with Eastern Equine Encephalitis have no apparent illness, however, some can be very ill. Severe cases of Eastern Equine Encephalitis (involving encephalitis, an inflammation of the brain) begin with the sudden onset of headache, high fever, chills, and vomiting 4 to 10 days after a mosquito bite. The illness may then progress to disorientation, seizures, or coma.
"While we are always concerned about more common mosquito-borne diseases, like West Nile virus, we also need to be vigilant for rare, but severe viruses, like Eastern Equine Encephalitis," said Acting Health Commissioner Judith Persichilli. "Individuals who are concerned they may have Eastern Equine Encephalitis should contact their health care provider right away."
RELATED: More information about EEE is available from the New Jersey Department of Health
Eastern equine encephalitis has been diagnosed in 21 people in six states, and five people have died. The infection is only being seen in certain counties within a small number of states.
The U.S. each year has seen seven illnesses and three deaths, on average.
It's not clear why numbers are up this year, but for some reason cases seem to spike once every several years, Dr. Mark Fischer, an expert at the U.S. Centers for Disease Control and Prevention, said Wednesday.
Most infections occur in the summer, so health officials do not think it will get much worse.
Massachusetts, Michigan, Rhode Island, and North Carolina have also reported cases.
A human case surfaced in Connecticut earlier this week, prompting a school district to hire a company to spray insect repellant near athletic fields at its schools in response to the threat of eastern equine encephalitis.
The virus is spread to people through mosquitoes that mostly feed on infected birds but sometimes bite humans.
Cases are generally confined to New England and states along the Gulf of Mexico or Great Lakes, usually in or near swamps.
The uptick in cases has prompted health warnings in some places and even calls to cancel outdoor events scheduled for dusk - when mosquitoes are most active. Precautions include using mosquito repellent and wearing long sleeved shirts and long pants outdoors.
Scientists first recognized eastern equine encephalitis as a horse disease in Massachusetts. There's a vaccine for horses, but not people.
It's not considered as large a concern as West Nile virus, which also is spread by mosquitoes, and is seen in most states. Nearly 500 West Nile illnesses, including 21 deaths, have been reported to CDC so far this year.
Some information from The Associated Press
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