FDA recommends updated Covid booster shots for fall targeting Omicron spinoff XBB.1.5.

The FDA has recommended that Covid-19 vaccine manufacturers prepare updated boosters targeting the XBB.1.5 strain, which accounts for about 40% of infections in the US. The FDA also wants vaccine makers to continue testing the updated booster in trials to demonstrate that it will likely offer protection against severe disease and hospitalizations. The rollout of the next booster could begin in September, coinciding with the availability of the newest flu vaccine. Only 17% of eligible Americans have received a bivalent booster, which was most recently recommended by federal health agencies.