BOSTON — The Massachusetts Department of Public Health (DPH) announced two new human cases of West Nile virus (WNV) in the state late last week. Both individuals are male, one in his 50s and the other in his 70s, and both were exposed to WNV in Middlesex County.
Based on the three human cases, recent increases in WNV findings in mosquitoes, and weather favorable for mosquito activity, the WNV risk level in 38 communities is being raised from low to moderate, including six in Western Mass.: Agawam, Chicopee, East Longmeadow, Longmeadow, Springfield, and West Springfield.
The Greater Boston area and several towns in Bristol and Worcester counties were already at moderate risk for WNV. There have been no deaths this year associated with WNV.
“These are the second and third human cases of West Nile virus infection in Massachusetts this year, and we are seeing significant expansion of virus activity in mosquitoes,” acting Public Health Commissioner Margret Cooke said. “Risk from West Nile virus will continue until the first hard frost. As we enjoy the unofficial last weekend of summer and then head back to school and work, it is important for people to remember to continue to take steps to avoid mosquito bites.”
In 2020, there were five human cases of WNV infection identified in Massachusetts. WNV is usually transmitted to humans through the bite of an infected mosquito. While WNV can infect people of all ages, people over the age of 50 are at higher risk for severe disease. 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.