MASS. — A fourth case of West Nile Virus has been detected in Massachusetts.
On Friday, the Massachusetts Department of Public Health (DPH) announced two additional human cases of West Nile virus.
One is in a man in his 40s who was likely exposed to the virus in Hampden County, and the other is in a man in his 80s with exposure in Middlesex County.
These cases bring the total number of confirmed WNV infections this season to four.
As a result, risk levels for WNV have been elevated to high in Ashland, Framingham, Marlborough, Natick, Sherborn, Southborough, Sudbury, and Wayland.
“Given how many mosquitoes have been found carrying West Nile virus this summer, we expected that there would be human infections this year,” said Public Health Commissioner Robbie Goldstein, MD, PhD.
The first WNV-positive mosquitoes in the state this year were announced on June 17.
Since then, 376 mosquito samples have tested positive for WNV so far this season from Barnstable, Berkshire, Bristol, Dukes, Essex, Franklin, Hampden, Middlesex, Norfolk, Plymouth, Suffolk, and Worcester counties.
There has also been one animal case of WNV this year in a goat.
The risk for WNV is now high in 28 municipalities in Suffolk, Middlesex, Essex, and Worcester counties and moderate in 175 cities and towns in Barnstable, Berkshire, Bristol, Essex, Franklin, Hampden, Hampshire, Middlesex, Norfolk, Plymouth, Suffolk, and Worcester counties.
State officials shared the following tips to help prevent mosquito bites and the transmission of the virus:
Avoid mosquito bites and 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 the evening, after 6 p.m. or early morning. Otherwise, take extra care to use repellent and protective clothing. Mosquitoes can be active during daylight hours when the temperatures are cool.
Clothing can help reduce mosquito bites. Although it may be difficult to do when it is hot, wearing long sleeves, long pants and socks when outdoors will help keep mosquitoes away from your skin.
Apply insect repellent when you go outdoors. Use a repellent with DEET (N, N-diethyl-m-toluamide), permethrin, picaridin (KBR 3023) or oil of lemon eucalyptus [p-methane 3, 8-diol (PMD)] according to the instructions on the product label. DEET products should not be used on infants younger than 2 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 younger than 3 years of age.
Mosquito-proof your Home and 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 getting rid of items that hold water. Check rain gutters and drains. Empty any unused flowerpots and wading pools, and change water in birdbaths frequently.
Install or repair screens. Some mosquitoes like to come indoors. Keep them outside by having tightly fitted 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 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.
This is a developing story. Check back for updates as more information becomes available.
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