The bivalent Covid-19 vaccines, which also referred to as “updated boosters”, means that the vaccine causes the immune system to create antibodies (protection) against two different types of COVID-19 virus: the original SARS Cov-2 strain and the Omicron variants. There are two bivalent vaccines available from Moderna and Pfizer-BioNTech companies. These bivalent vaccines are believed to create a broader immune response and improve the strength and duration of protection against circulating Covid19 variants. The bivalent vaccine version is based on the type of omicron variant component, the first version contains mRNA from omicron variant BA.1, while the second/updated version contains the BA.4 and BA.5 lineages of the omicron variant.
Who is eligible to receive the bivalent Covid-19 vaccine?
The FDA authorized bivalent formulations of booster dose on August 31, 2022, for Moderna and Pfizer-BioNTech COVID-19 vaccines at least two months since the primary vaccination or the most recent booster dose of any authorized or approved monovalent COVID-19 vaccine. Moderna bivalent vaccine is given to individuals 18 years of age and older while Pfizer-BioNTech vaccine is given to individuals 12 years of age and older.
The eligibility for an updated bivalent COVID-19 vaccine booster does not need to be from the same manufacturer that made primary vaccine or previous booster with a monovalent COVID-19 vaccine.
Countries started the Covid-19 bivalent vaccines:
In August and September 2022, bivalent versions of the vaccine were authorized for use as booster doses in the United Kingdom, Switzerland, Australia, Canada, the European Union, and the United States. The second component of the version of the bivalent vaccine used in the United States (mRNA-1273.222) is based on the Omicron BA.4/BA.5 variant, while the second component in the bivalent vaccine version used in other countries (mRNA-1273.214) is based on the Omicron BA.1 variant.
Recent study from the USA published on December 2, 2022, in the Morbidity and Mortality Weekly Report (MMWR) of the CDC, stated that the bivalent boosters provided significant additional protection against symptomatic SARS-CoV-2 infection in persons who had previously received 2, 3, or 4 monovalent vaccine doses.
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