State health officials announce third case of West Nile virus in Massachusetts, remind about EEE

BOSTON (October 10, 2019)—The Massachusetts Department of Public Health (DPH) today announced that state laboratory testing has confirmed the third human case of West Nile virus (WNV) infection, a man in his 60s from Middlesex County. The man was exposed to the virus last month and there are no risk level changes at this time.

“We continue to emphasize the need for people to protect themselves from mosquito bites,” said Public Health Commissioner Monica Bharel, MD, MPH. “Although mosquito populations are declining, some risk will continue until the first hard frost.”

The other two human cases of WNV this season involved a man in his 60s from Middlesex County and a man in his 50s from Plymouth County. There have also been 12 human cases of Eastern Equine Encephalitis (EEE) virus infection, a rare but serious and potentially fatal mosquito-borne disease that can affect people of all ages. Eight horses and a goat have also been confirmed with EEE this season.

State health officials continue to remind residents throughout the Commonwealth to take personal precautions to prevent mosquito bites.

There are 15 communities at moderate risk for WNV.

People have an important role to play in protecting themselves and their loved ones from illnesses caused by mosquitoes:

Avoid Mosquito Bites

Apply Insect Repellent when Outdoors. Use a repellent with an EPA-registered ingredient (DEET (N, N-diethyl-m-toluamide), permethrin, picaridin (KBR 3023), oil of lemon eucalyptus [p-methane 3, 8-diol (PMD)] or IR3535) according to the instructions on the product label. DEET products should not be used on infants under two months of age and should be used in concentrations of 30% or less on older children. Oil of lemon eucalyptus should not be used on children under three years of age.

Be Aware of Peak Mosquito Hours

The hours from dusk to dawn are peak biting times for many mosquitoes. Consider rescheduling outdoor activities that occur during evening or early morning in areas of high risk.

Clothing Can Help Reduce Mosquito Bites

Wearing long-sleeves, long pants and socks when outdoors will help keep mosquitoes away from skin.

Mosquito-Proof Your Home

Drain Standing Water. Mosquitoes lay their eggs in standing water. Limit the number of places around your home for mosquitoes to breed by draining or discarding items that hold water. Check rain gutters and drains. Empty unused flowerpots and wading pools and change the water in birdbaths frequently.

Install or Repair Screens. Keep mosquitoes outside by having tightly-fitting screens on all of your windows and doors.

Protect Your Animals

Animal owners should reduce potential mosquito breeding sites on their property by eliminating standing water from containers such as buckets, tires, and wading pools – especially after heavy rains. Water troughs should be flushed out at least once a week during the summer months to reduce mosquitoes near paddock areas. Horse owners should keep horses in indoor stalls at night to reduce their risk of exposure to mosquitoes. Owners should also speak with their veterinarian about mosquito repellents approved for use in animals and vaccinations to prevent WNV and EEE. If an animal is suspected of having WNV or EEE, owners are required to report to DAR, Division of Animal Health by calling 617-626-1795 and to the Department of Public Health (DPH) by calling 617-983-6800.