New York state is facing an unusual increase in mosquitoes carrying the deadly Eastern Equine Encephalitis (EEE) virus, which has already caused one rare death in the state and led officials to declare an “imminent threat.”
The state’s surveillance system typically detects EEE-positive mosquitoes in two or three counties each year, but this year it has seen infections in 15 counties across New York, said state Health Commissioner James McDonald. Said this week.
“This year’s Eastern equine encephalitis is different,” MacDonald said, referring to the disease’s deadly nature, with a mortality rate of 30 to 50 percent. “Mosquitoes were once a nuisance, but now they’re a threat,” MacDonald added. “We urge New Yorkers to protect themselves from mosquito bites by using insect repellent, wearing long sleeves and removing standing water near their homes. Fall is officially here, but mosquitoes will be around until we experience multiple nights of sub-freezing temperatures.”
On Monday, McDonald declared EEE an imminent public health threat, and Governor Kathy Hawkle announced statewide measures to prevent infection. At the same time as the declaration, officials reported the death of a New York resident with EEE. The case, confirmed in Ulster County on September 20, is the state’s first case of EEE since 2015.
The disease is extremely rare in New York State: between 1971 and 2024, only 12 cases of EEE were reported in the state, seven of which were fatal.
Rare but deadly
EEE is generally rare in the United States, with an average of only 11 cases reported per year, according to the Centers for Disease Control and Prevention. Centers for Disease Control and PreventionThe virus lurks in wild birds and spreads to humans and other animals via mosquitoes. As its name suggests, the virus is particularly deadly to horses, with a mortality rate of Up to 90 percentIn humans, being bitten by a mosquito carrying the EEE virus rarely results in EEE. In fact, the CDC estimates that only about 4-5% of infected people develop the disease, with the majority remaining asymptomatic.
In people with EEE, the virus travels from the mosquito bite to the lymphatic system, where it spreads and causes a systemic infection. Early symptoms are non-specific, including fever, headache, fatigue, chills, joint pain, nausea, and vomiting. This can progress to brain inflammation and neurological symptoms, including mental status changes and seizures. Children under 15 and adults over 50 are most at risk.
The CDC estimates that about 30% of people who develop severe EEE will die from the disease. However, reported death rates are subject to change as fewer cases are identified over time. For example, in Massachusetts, About 50 percent Many cases are fatal. Many who recover from the neuroinvasive disease are left severely disabled and some die from complications within a few years. There is no vaccine for EEE and no specific treatment.
Overall figures
While New York appears to be experiencing an unusual increase in EEE-positive mosquitoes, the number of cases across the country is not necessarily on the rise. Just 10 from 6 states There have been 11 cases reported to the CDC this year. This number does not include cases in New York, which would bring the total to 11, the same as the national average annual number of cases.
In addition to New York, cases have been reported in Massachusetts, Vermont, New Jersey, Rhode Island, Wisconsin and New Hampshire. Most of the cases are in the Northeast, where cases tend to be reported between mid-June and early October, before freezing temperatures kill off the mosquitoes.
The New York death is the second death from EEE this year. In August, the New Hampshire Department of Health reported deaths in EEE casesAccording to local media reports, this person A 41-year-old healthy man from Hampstead.
EEE gained attention last month when a small town in Massachusetts urged residents to follow a nighttime curfew to avoid mosquito bites. The move came as the state announced its first case of EEE this year (the state’s case count now stands at four) and said, “Significant risk levelIn four communities.
From 2003 to 2023, the year with the highest number of cases per year was 2019, with each state reporting 38 EEE cases.
