FRAMINGHAM – Flu cases in Massachusetts are on the rise.
Thus far, this season, more than 5,700 cases of the flu have been reported.
That’s a 228 perecnt increase over last season.
The U.S. Centers for Disease Control and Prevention has called it the worst season in 10 years.
Its severity is blamed on a strain of type A, H3N2, more widely in circulation this year and against which the flu vaccine is not as effective, partly because of the way it is made. There are indications that type B flu viruses – against which the vaccine is more effective – are starting to increase in circulation, said the CDC.