Mosquitoes carrying West Nile Virus have been found in Greenfield and Bernardston, although no human or animal infections in the state have been reported.
The Massachusetts Department of Public Health on Friday notified local officials of its findings.
The samples were taken on Wednesday and are the first reports of West Nile Virus in the mosquito population in Franklin County this year, based on information from the Massachusetts Department of Health and Human Services website.
The virus has been spreading across the state recently, with confirmed reports of West Nile Virus infected mosquitoes in 57 communities since June 20.
Other nearby communities, including Northampton, Amherst, Holyoke and several locations in Berkshire County, also have confirmed cases.
According to a press release from the Greenfield Health Department, the risk from the finding is considered moderate. The department said “currently there is no recommendation to curb activities,” but residents should take steps to reduce being bitten by mosquitoes.
To avoid mosquito bites, the health department recommends applying insect repellent when outdoors, with ingredients including DEET, permethrin, picaridin or oil of lemon eucalyptus.
Children two months or younger should not have DEET products applied, and for older children the concentration of the chemical should be 30 percent or less, according to the department.
Oil of lemon eucalyptus shouldn’t be used on children under 3 years old.
Contact your veterinarian before using repellents on animals.
The department recommends long-sleeved shirts, long pants and socks for protection, as well.
The department also recommends avoiding peak mosquito hours, which are from dusk to dawn.
To help reduce the breeding grounds for mosquitoes near homes, residents can drain standing water and change water in birdbaths around every two to three days. This is beneficial to humans and animals.
Making sure homes have tight-fitting screens can also reduce the potential for mosquitoes in the home.
People are most often exposed to mosquitoes from August to early September, the health department said.
West Nile Virus can cause a fatal neurological disease in humans, according to the World Health Organization website, though about 80 percent of people infected will not have symptoms.
The disease is mostly transmitted through mosquito bites.
The virus can be deadly to horses but vaccines for the animal are available. There is no vaccine for humans.
Of the roughly 20 percent of humans who become infected and symptomatic, they may develop West Nile fever or severe West Nile disease, according to the WHO website.
Symptoms of West Nile fever include fever, headache, tiredness, body aches, nausea, vomiting, occasional skin rash and swollen lymph glands.
Symptoms of severe West Nile disease, also known as West Nile encephalitis or meningitis, include headache, high fever, muscle weakness, neck stiffness, stupor, disorientation, coma, tremors, convulsions and paralysis.
The WHO reports that “1 in 150 persons infected with the West Nile virus will develop a more severe form of disease.”
While this can happen at any age, people over 50 and those with weak immune systems are at the highest risk for the severe form.
Diagnosis of the disease can be achieved through various tests.
Treatment of the severe disease include hospitalization, fluid therapy, respiratory support and infection prevention.