West Nile virus was first detected in birds and mosquitoes in Massachusetts in 2000. Between 2001 and 2015, 143 people were infected with WNV in Massachusetts.
Massachusetts has the second largest number of reported human cases of eastern equine encephalitis in the country. Between 2004 and 2013, 82 people in the U.S. were infected with the EEE virus. Of these people, 29% (24 individuals) were infected in Massachusetts. There were no human cases of EEE virus infection identified in Massachusetts in 2014 or 2015.
Please note that EEE is not considered a threat to residents of Cambridge and surrounding cities. While mosquitoes with EEE are trapped in the area once every few years, this is a very rare occurrence.
The area of highest risk for transmission of EEE continues to be southestern Massachusetts, which is the historic area of risk. However, over the last 10 years, human infections of EEE have been acquired outside of these historic areas of risk, according to a 2015 report from the Massachustts Department of Public Health. Over the past several years, infected mosquitoes have been detected in Plymouth, Bristol, Franklin, Middlesex, Worcester, Norfolk, and Essex counties.
Revised on June 24, 2016