Do I need a Covid-19 booster shot? Answers on how to stay protected

While vaccine-induced immunity may not last forever, it is not clear when a booster will be needed

The increasing prevalence of new coronavirus variants is raising questions about how well protected those who’ve already had their COVID-19 shots are against evolving forms of the SARS-CoV-2 virus. Here, microbiology and infectious disease specialist William Petri of the University of Virginia answers some common questions about COVID-19 booster shots.

1. What is a booster shot?

Boosters are an extra dose of a vaccine given to maintain vaccine-induced protection against a disease. They are commonly used to bolster many vaccines because immunity can wear off over time. For example, the