Decoded: Understanding the debate over coronavirus booster shots

US Centers for Disease Control and Prevention recommends that ad­ults receive boosters of the tetanus vaccine every dec­a­de

With the especially contagious delta variant threatening efforts to end the pandemic, a growing number of wealthy countries are planning or considering administering booster shots of Covid-19 vaccines, at least to particularly vulnerable groups. Officials at the World Health Organization have characterised this course of action as unethical as long as poorer countries still lack supplies to cover significant portions of their populations with initial doses. They argue that the strategy could wind up prolonging the pandemic, as well.

What’s a booster shot?

The term traditionally has re­f­er­red to an additional dose of a vaccine given some time after the initial course