Exaggerated media reporting during the initial months of the COVID-19 vaccine rollout stoked the global spread of rumours about alleged adverse events, a study has found.

Traditional journalists remain crucial in fact checking to prevent the spread of rumours, but health professionals also have a role by promoting their perspectives when they believe a story about adverse events needs clarifying, the authors say.

The University of Western Australia research used Google trends data and social media activity monitoring tools to trace the emergence and dissemination of prominent COVID-19 vaccine rumours from December 2020 to 21 April 2021.

Online discussion of clotting, fainting, infertility, Bell’s palsy and the death of US baseball legend Hank Aaron were among the topics analysed.