Vaccines and immunizations Archive

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Not only is obesity a risk factor for flu complications, but it might actually make the flu vaccine less effective, says a study published online June 6, 2017, by the International Journal of Obesity. Scientists at the University of North Carolina at Chapel Hill found that the flu shot provides less protection in people who are obese.

The study compared flu rates in 1,022 people during two recent flu seasons. All participants were vaccinated against the flu. The researchers looked at immune response to the vaccine and also tracked who went on to get the virus. They found that nearly 10% of obese participants got the flu, compared with 5% of their healthy-weight counterparts. This is bad news, because individuals with a body mass index of 40 or higher are also more prone to flu complications.

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Q. I always get an annual flu shot, but should I get it closer to the official beginning of flu season?

A. In simplest terms, the best time to get a flu shot is anytime you can. Waiting for the "perfect" time could cause you to procrastinate and miss the benefit of a yearly vaccination against the flu, which prevents 50% to 60% of the influenza infections in a typical season. But if you want to time it so it's closer to the typical flu season, October is ideal.

The best time to get an annual flu shot is in mid-October. However, it’s not too late to get the shot in December, since people are still at risk of getting flu for several more months.