PROVIDENCE — The Rhode Island Department of Environmental Management confirmed Thursday that a horse in Westerly tested positive for Eastern Equine Encephalitis on Aug. 24. DEM also confirmed that the third positive finding of EEE in Rhode Island in 2019 was detected in a mosquito pool trapped at Chapman Swamp, in Westerly, on Aug. 19. The horse, a male 6-month-old Belgian, was too young to be vaccinated for EEE, and it was euthanized on Aug. 24.
Twenty-eight traps were set across Rhode Island on Aug. 19. The traps yielded 170 pools, or samples, of mosquitoes. A trap collected at Chapman Swamp consisted of mosquitoes belonging to a species called Culiseta melanura, which feeds almost exclusively on birds and is the primary carrier of EEE in the region. It included one mosquito that tested positive for EEE. Mosquitoes carrying the EEE virus have previously been found in Chapman Swamp in 1996, 2003, 2013, and 2016.
DEM confirmed the first two positive EEE findings in Rhode Island in mosquito samples collected in Central Falls on Aug. 15. To date, statewide, no mosquitoes have tested positive for West Nile Virus. Massachusetts, which, historically has had a higher prevalence and risk of EEE than Rhode Island, has conducted aerial mosquito spraying in Bristol, Plymouth, and other counties. DEM said that officials are continuing to assess the risk of human disease daily and are closely evaluating the need for aerial spraying. This includes weighing the threat from mosquitoes against the possible environmental impacts of aerial spraying.
DEM and the Rhode Island Department of Health said that resident should take precautions to protect themselves and their loved ones from being bitten by mosquitoes. Using repellent, wearing long sleeves and pants, and minimizing outdoor time from dusk to dawn all are important precautions.
On Monday, the health departmetn recommended that schools and municipal leaders not schedule games, practices, and other outdoor activities during the early morning or dusk hours. The “smart scheduling” of events is intended to help minimize the risk of mosquito bites for players, coaches, and spectators. The department recommended that smart scheduling stay in effect for the remainder of the mosquito season, which typically ends in mid-October after the first hard frost.