New Canadian research published this week has found this season’s flu shot is less effective than previously thought and in some cases may actually increase a person’s risk of becoming ill.
“Unfortunately this year the vaccine hasn’t worked at all,” says study co-author Dr. Jim Dickinson of the University of Calgary. “The reason for that is we have a version of the H3N2 virus that has moved away from the vaccine strain we’re using.”
The research published in the journal, Eurosurveillance also found the flu shot’s effectiveness diminishes if people received the vaccine 2 years in a row.
The study states, ” In particular VE (vaccine effectiveness) against influenza A (H3N2) among those who received the 2014/2015 influenza vaccine without prior vaccination in 2013/14 was higher (43%) than among participants who were vaccinated with the same A (H3N2) vaccine component in both 2013/14 and 2014/15 (- 15 %)”
“A negative effectiveness suggests the vaccine made people more susceptible to the flu,” Dr. Dickinson says, “We need to do further research to understand why this has happened.” (continue reading)