West Nile Virus Detected in Massachusetts Mosquitoes

For the first time this year, the Massachusetts Department of Public Health has announced the detection of West Nile virus in mosquitoes. This finding came from a sample collected on Saturday in Shrewsbury.

Public Health Commissioner Dr. Robbie Goldstein noted, “Mid-June is earlier than we typically first find West Nile virus-infected mosquitoes in Massachusetts. WNV activity is very difficult to predict in advance, which is why the mosquito surveillance system is so important.”

The virus spreads to humans primarily through infected mosquito bites. So far in 2024, there have been 19 human cases of West Nile virus reported. In comparison, last year the virus was first identified in mosquitoes towards the end of June. Interestingly, no human or animal cases have been identified as of now this year.

Additionally, there is currently no sign of Eastern equine encephalitis (EEE), another virus encountered sporadically in Massachusetts, which had four reported human cases in 2024.

While anyone can contract West Nile virus, those over 50 years old are at increased risk for more serious health issues. Most people infected may not show symptoms at all, though common symptoms include fever and flu-like symptoms. In rare circumstances, more severe illness may occur.