Boston is at high risk from West Nile virus

Boston is one of eight communities in Massachusetts where the risk of infection with the West Nile virus is now considered high, health officials said Friday.

The other seven communities at high risk for the virus, which can cause severe illness, are in Plymouth County, according to the Massachusetts Department of Public Health: Abington, Brockton, East Bridgewater, Marion, Mattapoisett, Rochester and Whitman.

Much of the rest of eastern Massachusetts is at moderate risk of West Nile virus transmission, according to the update, and other parts of the state are also at risk. Two people have been diagnosed with West Nile virus in Massachusetts so far this year, the first in Hamden County.

“The risk of [West Nile virus] is quite widespread this year,” said Dr. Catherine M. Brown, state epidemiologist, in a statement. “In addition to using mosquito repellent with an EPA-approved active ingredient and wearing clothing to reduce exposed skin, we recommend that people check your window screens to make sure they don't have holes in them and empty any containers in your yard that collect water.”

The state monitors mosquitoes for West Nile virus and EEE every year. What's different this year is that there is a risk for both EEE and West Nile virus.

Massachusetts is also monitoring the spread of Eastern Equine Encephalomyelitis, another mosquito-borne disease, and last week reported the state's first human case of EEE in years. A man in his 80s was exposed to the disease in Worcester County.

Some communities in Massachusetts are considering restricting outdoor activities at dusk, when mosquitoes are active, because of the risk of transmission.

Explore the West Nile Virus and EEE map here.

West Nile virus typically causes fever and flu-like symptoms, but in rare cases it can cause severe illness. There were six human cases in Massachusetts last year. EEE is rare but poses a serious threat to infected people of all ages.