Two more mosquito samples from the Manorville area have tested positive for Eastern equine encephalitis, a rare but potentially deadly virus, Suffolk County health officials said Thursday.

Suffolk Health Commissioner Dr. James Tomarken declared an “imminent threat to public health” last week after the virus was confirmed in a mosquito sample collected Aug. 16, also in the Manorville area. The latest samples containing the virus were collected Aug. 22.

The declaration triggered emergency state funding to fight the spread of the virus, allowing the county to take action this week to control mosquitoes in Manorville and vicinity, officials said.

No samples in Nassau have tested positive for equine encephalitis so far. There have been no human cases reported in either county.

Spread by bites, the disease is also a concern for horses, but while there is a vaccine for those animals, none exists for humans.

The illness is less common in humans because the primary mosquito carrying the virus, Culiseta melanura, typically does not feed on people, health officials said.

Tomarken said other mosquitoes can carry the virus by feeding on infected birds.

Symptoms include headaches, high fever, chills and vomiting, and encephalitis can be deadly, causing a swelling of the brain in severe cases, officials said. About 33 percent of people who develop Eastern equine encephalitis die.

New York State has reported 12 human cases since 1952.

Health officials on Thursday also said 12 mosquito samples in these Suffolk communities tested positive for West Nile virus, bringing the total to 104 this year: Port Jefferson Station, Setauket; Stony Brook; Melville; Bay Shore; Nesconset; Huntington Station; Northport; Greenlawn; South Huntington and Huntington.

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With Patricia Kitchen