It’s not too late. If you haven’t had a flu shot yet you can still get one. But what does it do for you?
A Cochrane review in 2010 looked at all influenza vaccination trials in adults. In the background of the report, the authors reminded us that even if the vaccine were 100% effective against influenza A & B – its intended targets – these viruses only account for about 10% of all flu-like illness in an average flu season.
The authors concluded that between 33 and 100 people need to be vaccinated to prevent one symptomatic case of the flu. This range is based on the variation in how well the vaccine components match the actual flu strains in the season. Vaccination was not found to reduce lost work days, hospital days, or flu deaths, at least not that the collective weight of these studies could find.
The review authors even suggested that their results might be optimistic, because almost half of the trials were funded by vaccine manufacturers. Drug company-funded studies tend to find larger effect sizes than non-Pharma-funded studies.
Also, let’s not forget that cost-effectiveness studies, as expected, show that influenza vaccination does not save money. The actual cost projections are widely variable, because, as expected, there are vastly different assumptions about the cost and effectiveness of the vaccine.
Go get your flu shot. Just take a large dose of humility about what it will actually do for you at the same time.