Two more people have contracted the severe mosquito-borne illness, Eastern equine encephalitis, bringing the total number of cases in the state to three, state health officials said.

The two cases were confirmed on Thursday in Atlantic and Union counties, according to a statement from the New Jersey Department of Health.

Officials say that EEE, a rare virus that infects humans and horses, has been detected in 65 mosquito samples in 13 counties the state.

The first human case came in August.

EEE recently caused the death of five horses in the state, and so far this year the virus has infected 10 animals, including nine horses and one alpaca, according to the state Department of Agriculture.

EEE is among the most serious mosquito-transmitted diseases in the U.S., killing around one-third of patients who contract it and often leaving survivors with significant brain damage.

While a vaccine exists for horses, there is no vaccine for people, state health officials said. The only way to protect yourself is by taking measures to prevent mosquito bites.

While most people infected with EEE will show no signs of illness, some will. In severe cases, the disease — which can cause inflammation of the brain — starts with a sudden headache, high fever, chills and vomiting four to 10 days following a mosquito bite, state health officials said.

Symptoms may develop into disorientation, seizures, or coma.

Health officials are also asking clinicians to be on alert for EEE in people who may be displaying symptoms. They should contact their local health department to ask about testing, which can only be done at the state Public Health and Environmental Laboratories.

“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.”

It’s vital, officials say, that people take precautions to protect against mosquito bites, whether using repellent when outside, wearing protective clothing, empty standing water, clean up any trash or leaves.

Clinicians are required to report human EEE cases to the local health department where the patient lives within 24 hours of diagnosis.

Residents who need assistance controlling mosquitoes around their home can call their county mosquito control agency or 1-888-666-5968.

Spencer Kent may be reached at skent@njadvancemedia.com. Follow him on Twitter @SpencerMKent. Find NJ.com on Facebook.

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