The World Health Organization's vaccine advisory panel recommends that people who are immunocompromised or received an inactivated vaccine should receive a booster dose of a COVID-19 shot, the head of the panel said on Thursday.

The recommendation comes after the Strategic Advisory Group of Experts (SAGE) on immunization held a meeting on Tuesday to evaluate the need for COVID-19 boosters.

Speaking in a briefing, SAGE chair Alejandro Cravioto said emerging data shows that vaccines' efficacy against COVID-19 wanes, with a significant decline seen in older people in particular.