BOSTON — Massachusetts health officials on Thursday, Sept. 3, announced the sixth human case of West Nile virus in the state this year, in a man in his 70s likely exposed in Suffolk County outside Boston, and raised risk levels in four additional communities.
The Department of Public Health (DPH) said the new case pushed the high-risk designation to 11 municipalities: Boston, Brookline, Cambridge, Chelsea, Everett, Malden, Newton, Revere, Somerville, Watertown and Winthrop. Another 250 cities and towns across 13 counties carry a moderate risk rating.
Public Health Commissioner Robbie Goldstein urged residents heading into the holiday weekend to stay alert to mosquitoes even amid backyard gatherings and cookouts. He recommended wearing repellent, covering exposed skin and clearing standing water around homes to cut down on breeding sites.
State officials reported 273 mosquito samples testing positive for West Nile virus so far this season, drawn from 13 counties including Barnstable, Middlesex, Worcester, and Suffolk. The first positive samples turned up June 16. Separately, 13 samples have tested positive for Eastern equine encephalitis, though no human or animal cases of that disease have surfaced this year.
Ways to Protect Your Family and Pets
Avoid Mosquito Bites
Apply Insect Repellent when Outdoors.Use a repellent with an EPA-registered ingredient, such as DEET (N,N-diethyl-m-toluamide), permethrin, picaridin (KBR 3023), or oil of lemon eucalyptus (p-menthane-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 percent 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 your 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 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 provide excellent mosquito breeding habitats and should be flushed out 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 West Nile virus (WNV) and EEE. If an animal is suspected of having WNV or EEE, owners are required to report to the Department of Agricultural Resources, Division of Animal Health by calling 617-626-1795, and to the Department of Public Health by calling 617-983-6800.
The department updates its arbovirus surveillance dashboard, including a downloadable risk-level file by city and town, and can be reached with questions through its Division of Epidemiology at 617-983-6800.
