Due to emergence of the highly contagious omicron variant that spreads more quickly when compared to the original SARS-CoV-2 virus and other variants, the emergency use authorization of coronavirus vaccine was modified by Food and Drug Administration (FDA) on 7 January 2022.

In people aged eighteen years and more, the interval between finalization of primary series of vaccine and administration of booster dose was reduced to at least 5 months, thus bringing consistency in the timing for booster dose administration among the currently available mRNA vaccines for COVID-19 management.

Getting vaccinated is indeed the best defense against coronavirus disease, including the circulating variants. Reducing the time interval between finalization of a primary series and a booster dose might assist to improve the decreasing immunity.

Redness, pain, swelling at the injection site, chills, headache, fatigue, joint or muscle pain were the most commonly noted adverse effects by people who were given a booster dose of coronavirus vaccine after completing the two-dose primary series.