The Massachusetts Department of Public Health is updating its list of West Nile virus cases this year to include an animal fatality in Franklin County.
A horse there died after becoming infected, officials said on Friday.
Four more human cases from Middlesex and Plymouth counties were also reported, with all of the victims requiring hospitalization, driving the total number in the state this year to 42.
The health department warns mosquito season isn't over yet.
(Photo credit ROSLAN RAHMAN/AFP/Getty Images)