The protection offered by the updated Covid-19 booster appears to be holding up against the newest Omicron subvariants that are sweeping across the country, scientists from the Centers for Disease Prevention and Control reported Wednesday.
A new study published in one of the agency’s online journals reported that the bivalent vaccine’s effectiveness against the XBB and XBB.1.5 strains is similar to what was seen when the BA.5 strain of the virus was circulating. The bivalent vaccine, which was introduced in September, targets the original strain of the SARS-CoV-2 virus as well as the BA.4/5 strains.
Early studies measuring neutralizing antibody responses to the new XBB subvariants raised concerns that the mutations contained in the new strains would further erode the protection generated by the vaccine. But that does not appear to be playing out in the real world, the CDC scientists suggested in a media briefing.advertisement
“So bottom line … is we did not see reduced vaccine protection against symptomatic illness for XBB and XBB.1.5, compared with those other recent BA.5 variants,” said Brendan Jackson, who currently heads CDC’s Covid response.
“Quite reassuring.”advertisement
The article, published in the journal Morbidity and Mortality Weekly Report, looked at data from Covid tests conducted at pharmacies during the period from Dec. 1, 2022, …