from The Conversation
– this post authored by Derek Gatherer, Lancaster University
I recently had my annual flu shot. Along with all the others who’ve received it, I’ll be hoping that it does the job of preventing me catching flu this winter – or at least reducing the severity of the disease if I do get it. Most years, it works, but occasionally things don’t go to plan. Winter 2014-2015′s vaccine was considerably less effective than usual and the flu caused 3,000 excess deaths per week in the UK alone in January 2015.