Massachusetts public health officials raise West Nile virus risk level to moderate statewide
Residents urged to take precautions to avoid being bitten by mosquitoes
BOSTON (August 21, 2018) – The Massachusetts Department of Public Health (DPH) today announced it was raising the risk level for West Nile virus from low to moderate in every Massachusetts city and town and urged residents to take precautions against mosquito bites.
Of the 351 cities and towns in Massachusetts, 162 communities are already considered to be at moderate risk for West Nile virus.
This is only the second time that public health officials have raised the risk level statewide. To date, there have been no reported human WNV cases in Massachusetts.
“The hot, humid weather in Massachusetts combined with frequent heavy rainfall has provided perfect conditions for mosquito species carrying West Nile Virus to breed,” said Public Health Commissioner Monica Bharel, MD, MPH. “I strongly encourage everyone to keep using insect repellant and to be especially aware of mosquito activity at dusk and dawn when the risk of being bitten by mosquitoes is greatest. Move indoors if you are getting bitten.”
While WNV can infect people of all ages, people over the age of 50 are at higher risk for severe disease. WNV is usually transmitted to humans through the bite of an infected mosquito. Most people infected with WNV will have no symptoms. When present, WNV symptoms tend to include fever and flu-like illness. In rare cases, more severe illness can occur.
“August and September are the months when most human cases occur,’’ said DPH State Epidemiologist Dr. Catherine Brown. “That’s why we are taking this step today so together we can help keep people from getting sick.”
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 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 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.
More information, including all WNV and EEE positive results, can be found on the Arbovirus Surveillance Information web page at www.mass.gov/dph/mosquito or by calling the DPH Epidemiology Program at 617-983-6800.