The death of 21 people over 40 days in a single Karnataka district has brought focus on the possible links between Covid vaccines and sudden heart attacks. The state government has ordered a probe into the deaths in Hassan and is expecting a report in 10 days. But it’s unlikely that any conclusive evidence of the link would emerge.
Studies worldwide have reported a high degree of uncertainty on such a link, but that has not stopped speculation. A study conducted last year in South Korea’s Yonsei University College of Medicine revealed a higher risk of heart disease among individuals receiving mRNA vaccines than the other types, but no significant link between the vaccine type and the risk of “acute heart disease”. The study also noted that younger individuals receiving mRNA vaccines (like Gemcovac-OM, an Omicron-specific booster vaccine used in India) had a higher risk than older individuals.
On the other hand, a 2024 study by University of Minnesota’s Centre for Infectious Disease Research and Policy—on data of 46 million adults gathered by the British Heart Foundation—had found that adenovirus-based Covid vaccines, which includes the Covishield variety widely used in India, potentially caused thrombotic thrombocytopenia, or clotting in small blood vessels causing a drop in platelet count, red blood cell breakdown and potential organ damage. Meanwhile mRNA-based vaccines were found to potentially cause slightly increased rates of myocarditis, an inflammation of the muscular layer of the heart wall that weakens the organ’s ability to pump blood, and pericarditism, an inflammation of the sack-like structure surrounding the heart that can cause chest pain and, in some cases, serious complications. However, the study also indicated that the incidence of cardiovascular diseases dropped after every Covid vaccination.
So, while the Indian Council of Medical Research claims to have conclusively proved the lack of a direct link between Covid vaccines and sudden deaths, other studies have relayed confusing signals on the vaccines’ safety for cardiovascular health. As the scientific community pursues an accurate proof, the importance of evidence-based public health measures cannot be ignored. This must include focusing on the role played by underlying health issues, genetic predisposition and risky lifestyle choices in unexplained deaths. And that—as much as the safety of vaccines—needs urgent attention for a healthier India.