evidence: The Health Sciences Authority (HSA) is aware of a Swiss study published in the scientific journal, European Journal of Heart Failure, which reported that 22 out of 777 (i.e. 1 in 35) people who received the COVID-19 mRNA booster vaccine had heart injuries.1 HSA has reviewed this study as part of our ongoing safety surveillance of COVID-19 vaccines, and assessed that the benefit-risk profile of the COVID-19 mRNA vaccines remains positive. [...] 4 HSA will continue to closely monitor the safety of all COVID-19 vaccines used in Singapore and will inform members of the public should there be any significant new safety concerns.