Bivalent Covid-19 booster doses provided additional protection against Covid-associated emergency department or urgent care encounters and hospitalisations, according to a recent report of the US Centers for Disease Control and Prevention (CDC).
The CDC recommended the use of bivalent mRNA Covid-19 booster doses in September, which contain Omicron BA.4 and BA.5 sublineage component to better protect from the newest strains,reports Xinhua news agency.
Because of waning of monovalent vaccine-conferred immunity, effectiveness of bivalent vaccines was higher with increased time since the previous monovalent dose, according to the CDC.
Vaccine effectiveness of a bivalent booster dose after previous monovalent doses against Covid-19-associated hospitalisations was 57 per cent compared with no vaccination, and 45 per cent compared with previous monovalent dose vaccinated over 11 months earlier, CDC data showed.
Despite the promising numbers, vaccine uptake has been slim.
Only 14 per cent of eligible Americans ages 5 and older have received the Omicron-specific booster, according to a report of The Washington Post.
The CDC called on all people to stay up to date with recommended Covid-19 vaccinations, including receiving a bivalent booster dose if eligible.