BOSTON (WHDH) - A woman from Middlesex County has contracted the fourth confirmed human case of West Nile virus in Massachusetts this year, the Massachusetts Department of Public Health announced Monday.
The woman in her 50s was not hospitalized for her illness. Three other cases were reported on Friday.
Investigations conducted by health officials indicate that at least two of the four cases were exposed in the Greater Boston area.
The West Nile virus risk level has been raised from moderate to high for 11 communities in the area, including Arlington, Boston, Belmont, Brookline, Cambridge, Chelsea, Everett, Medford, Newton, Somerville, and Watertown.
“Several individuals from the same area have developed West Nile virus,” Public Health Commissioner Monica Bharel said. “That means that there is an increased risk in this specific area and that additional people could become infected. We are particularly concerned about people over 50 and those who are immunocompromised as they are the ones most likely to develop WNV disease.”
On Aug. 21, the risk level for West Nile virus was raised from low to moderate in every Massachusetts city and town. It was only the second time since the virus was first detected in the state in 2000 that health officials have raised the risk level statewide.
Six human cases of the virus were confirmed in 2017.
Bay Staters are urged to take the following steps to protect themselves:
Avoid Mosquito Bites
Apply Insect Repellent when Outdoors. Use a repellent with 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.
Clothing Can Help Reduce Mosquito Bites. Wear long-sleeves, long pants, and socks when outdoors to 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 either draining or discarding items that hold water. Check rain gutters and drains. Empty any 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 provide excellent mosquito breeding habitats and 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 diagnosed with 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.
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