Explained: The significance of expanding the use of Covid-19 booster shots in the US

In September, the US Centers for Disease Control and Prevention’s (CDC) Advisory Committee on Immunisation Practices (ACIP) recommended a booster shot of the Pfizer-BioNTech vaccine in certain populations and also recommended a booster dose for those in high-risk settings.

Out of the three vaccines that are being used against Covid-19 in the US, the ACIP booster shot recommendation was only meant for Pfizer’s vaccine at the time.

Before September’s announcement, in August, the FDA had authorised vaccine booster shots for transplant recipients and people with weakened immune systems to better protect them from variants of Covid-19.

What is the announcement made by the FDA on Wednesday?

Now, the FDA has authorised booster doses of all the three vaccines that are in use in the US at the moment. These three vaccines include the Moderna Covid-19 vaccine, Johnson and Johnson’s Janssen and the Pfizer-BioNTech Covid-19 vaccine. Apart from increasing the range of the eligible population for booster shots, the FDA has also allowed mixing and matching. This means that a person who has received two doses of one brand of a Covid-19 vaccine can receive a booster dose from a different brand.

Has the WHO encouraged booster doses yet?

The authorisation came even as the WHO placed a moratorium on Covid-19 boosters in August due to the disparity in vaccination levels in low- and high-income countries.

More recently, the WHO has said that the pandemic will drag on for a year longer than it needs to because poorer nations are not able to get sufficient quantities of vaccine doses.

Currently, the WHO maintains that the “current primary goal of immunisation” amidst the pandemic is to “protect against hospitalization, severe disease and death. Hence, booster doses may only be needed if there is evidence of insufficient protection against these disease outcomes over time”.

As per the latest data from Our World in Data, 48.1 percent of the world’s population has received at least one dose of the Covid-19 vaccine. Over 6 billion doses have been administered globally and about 22.25 million doses are administered each day. In low-income countries, only 2.8 percent of the population has received at least one dose.

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Who all are eligible for Covid-19 booster shots in the US now?

With Wednesday’s announcement, the use of a single booster dose of the Moderna Covid-19 vaccine can be administered at least 6 months after completion of the first two primary doses to the following individuals: those who are 65 years of age and older, 18 through 64 years of age at high risk of severe Covid-19 and 18 through 64 years of age with frequent institutional or occupational exposure to SARS-CoV-2.

The Pfizer-BioNTech vaccine booster is also meant to be given at least six months after the completion of the primary dose.

Further, a single booster dose of Johnson and Johnson’s Janssen vaccine can be administered at least two months after the completion of the primary first dose to those who are 18 years and older.

Lastly, the FDA has also approved the “mix and match” of booster doses in eligible individuals. Which means those who have completed their primary vaccination regimen.