After two years of a pandemic that has seen nearly 500 million people infected and billions vaccinated, the studies highlighted the importance of getting jabbed for those who have natural immunity after recovering from the disease
A health worker inoculates a woman with a third 'booster' dose of the Covid-19 coronavirus vaccine in Hyderabad on January 10, 2022, as the country sees an Omicron-driven surge in cases. (Credit: Noah SEELAM / AFP)