New Jersey is dealing with its highest presence in years of a rare but potentially deadly mosquito-borne illness.

Eastern equine encephalitis (EEE) was confirmed in two more people as of Thursday, with one case each in Union and Atlantic Counties, according to Kim Cervantes, vector-borne disease coordinator of the state health department.

That’s in addition to the first human case of EEE this year, reported Aug. 16 by the state health department as an “elderly Somerset County man” who was hospitalized but then discharged for continued rehabilitation care.

Cervantes says this is the highest number of human cases in almost 20 years for the state, while about half of New Jersey has seen a lot of EEE activity in mosquito samples, with positive tests for the disease in 13 counties as of Sept. 14.

Before this, a human case reported in Passaic County in 2016 was the state’s only other confirmed case over the past decade, based on CDC figures. 

Cervantes said it's a particularly busy year for EEE activity in other states, as well.

CNN reported among human cases of the EEE virus this year, there have been two deaths in Michigan, a death in Rhode Island and a death in Massachusetts.

EEE virus can cause brain infections (encephalitis), according to the CDC. While only a few cases are reported in the United States each year, roughly a third of people with EEE die, while many survivors have ongoing neurologic problems.

EEE, or “triple E” can present as a milder illness, with fever, muscle and joint pain among symptoms, Cervantes said.

She said while milder cases can resolve in one to two weeks with a full recovery, those patients generally aren’t tested for EEE and therefore they aren’t heard about.

But in others, the virus can progress to its most severe form, resulting in inflammation of the brain.

Last year, six human cases of EEE were reported nationwide, one of which resulted in a patient’s death, according to CDC data.

“Severe cases of EEE (involving encephalitis) begin with the sudden onset of headache, high fever, chills, and vomiting. The illness may then progress into disorientation, seizures, or coma,” according to the state department of health website, which also said symptoms typically appear between four to 10 days after exposure.

There is no specific treatment for EEE and there is no vaccine, Cervantes said.

Nine horses and one alpaca in NJ also have contracted the disease this year. All ten animals were euthanized.

Of the equine cases of EEE this year, five were in Ocean County, with one each in Atlantic, Monmouth, Morris and Salem counties. The single alpaca case of EEE was reported in Camden County.

Among the most recent areas to have a positive test for EEE activity, Berkeley Heights this week is spraying for mosquitoes around schools, parks and athletic fields in the township.

As of Sept 17, the township said there were no other areas in Union County with a positive test for the virus among mosquito samples.

The highest number of positive results throughout this season has been 10 in Atlantic County, followed by several each in Morris, Burlington, Monmouth, Sussex, Camden and Gloucester counties.

Ocean County has seen three positive results for the presence of EEE among mosquitoes, while Salem, Cape May, Hunterdon and Warren counties have each seen one positive test result, according to state data through Sept 14.

Residents can reduce the risk of being infected with EEE by using insect repellent, wearing protective clothing and staying indoors during the time of day when mosquitoes are most active.

Mosquitoes can lay eggs even in small amounts of standing water, as little as a bottlecap full.

State health officials recommend the following tips to discourage mosquitoes from breeding:

  • Empty standing water from flower pots, buckets, barrels and tires.
  • Change the water in pet dishes and replace the water in bird baths every week.
  • Drill holes in tire swings so water drains.
  • Drill bottom holes and elevate recycling containers that are left outdoors.
  • Aerate ornamental pools or stock them with fish.
  • Clean and chlorinate swimming pools that are not being used. Mosquitoes can breed in the water that collects on pool covers.
  • Use landscaping to eliminate standing water.

Cervantes also said residents should be aware that each county has a mosquito control agency, which can assess a property and help with concerns about mosquito activity.

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