Taking Covid booster and flu shots at same time in early autumn may be too early for the flu.

Push to double up on Covid booster and flu shot may have a downside, experts caution The protection from flu vaccines erodes pretty quickly over a flu season. A dose given in early September may offer limited protection by February or March. Helen Branswell STAT

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A number of studies have shown that the benefit of a flu shot wanes substantially over the course of a flu season — exacerbating effectiveness problems that are frequently seen when some of the strains in the vaccine aren’t well matched to the strains making people sick....