Rare Mosquito-borne Disease Infects 5 This Year

Today, health officials reported that a Hampstead, New Hampshire resident has died of eastern equine encephalitis (EEE)—the deadliest mosquito disease in North America with a mortality rate around 30%, according to the U.S. Centers for Disease Control and Prevention (CDC). As of Aug. 28, health officials have tracked five human cases this year.

EEE can result in neurologic diseases, such as meningitis and encephalitis, and has no specific treatment. Many people who recover are left with long-term physical or mental problems ranging from mild to severe intellectual disability and personality disorders to seizures, paralysis, and cranial nerve dysfunction.

The U.S. sees about a dozen human cases of EEE annually. Seven cases were reported to the CDC last year.

Earlier this month, Massachusetts health officials reported one case of EEE in an 80-year-old man in the southeastern part of the state. He became the first case Massachusetts has seen in four years, NPR reported. Still, health officials have found EEE activity in mosquitos in other parts of the state, and some towns have announced voluntary 6 p.m. curfews and closed parks at sundown to mitigate the risk of infection.

So far this year, three other human cases have been reported—one each in Vermont, New Jersey, and Wisconsin, according to the CDC. The virus also has been found active in mosquitos or other animals in Michigan, Florida, Georgia, Arkansas, Virginia, New York, Louisiana, New Hampshire, and South Carolina. 

Climate change has made the mosquito season longer as well as caused weather shifts making more areas of the U.S. suitable for mosquitos, NPR reported.

As CMM previously reported, August also ranks as the leading month for West Nile human infections— the most widespread mosquito-borne disease. As of Aug. 27, 289 West Nile disease cases have been logged in the U.S., including the hospitalization of  Dr. Anthony Fauci, former director of the National Institute of Allergy and Infectious Diseases. So far this year, 33 Americans have died from West Nile.

In June, the CDC also issued an advisory to notify the public of an increased risk of dengue virus infections in the U.S. This year, global cases of the mosquito-borne viral illness have been the highest on record.