Indeed - from my understanding, they have to "guess"timate which strains of Flu will be prevalent in a given year, if they get it right, fantastic - if they get it wrong, lower effectiveness. Of course, it's not really a guess so much as an educated assessment.
Having said that, as an asthmatic I've had the Flu vaccine every year for the last 20 or so years, and knock on wood haven't had Flu since. I also had the multivalent pneumonia vaccine a while ago, so fingers crossed!
Having said that, as an asthmatic I've had the Flu vaccine every year for the last 20 or so years, and knock on wood haven't had Flu since. I also had the multivalent pneumonia vaccine a while ago, so fingers crossed!