Fifth Human West Nile Virus Case in Massachusetts Confirmed 

The Massachusetts Department of Public Health (DPH) announced the fifth human case of West Nile virus (WNV) in a Massachusetts resident this year. The individual is a male in his 70s who was likely exposed in Hampden County.

Aedes aegypti mosquito
Aedes aegypti mosquito
Photo: USDA
BOSTON — The Massachusetts Department of Public Health (DPH) announced on Oct. 20 the fifth human case of West Nile virus (WNV) in a Massachusetts resident this year. The individual is a male in his 70s who was likely exposed in Hampden County.
 
The risk of human infection with WNV is moderate in the Greater Boston area (Middlesex, Norfolk and Suffolk counties), and in parts of Berkshire, Bristol, Hampden, Hampshire, Plymouth, and Worcester counties. No risk level changes are associated with this recent case.
 
“Although mosquito activity is decreasing with the cooler weather, some risk from mosquito-borne disease will continue until the first hard frost,” said Dr. Catherine M. Brown, State Epidemiologist. “People should continue to take steps to protect themselves from mosquito bites anytime they are outdoors.”
 

In 2022, there were eight 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.

Source: Mass.gov