AstraZeneca acknowledges rare side-effect of Covishield vaccine. Is there cause for concern?

TTS – a blood clot disorder — is a rare side effect of AstraZeneca’s Covid vaccine. This comes after reports said that AstraZeneca has for the first time accepted in court documents that its vaccine, developed in partnership with Oxford University, can raise the risk of a rare and serious blood clot.

The Oxford-AstraZeneca Covid vaccine, sold as Covishield in India and Vaxzevria in Europe, is a viral vector vaccine developed using the modified chimpanzee adenovirus ChAdOx1. Covishield, which is manufactured and marketed in India in partnership with Serum Institute of India (SII), was widely administered in the country and received by almost 90 per cent of the Indian population.

According to infectious disease expert Dr. Ishwar Gilada, TTS is a very rare but serious adverse effect that has occurred as part of Vaccine-induced Immune Thrombotic Thrombocytopenic Purpura (VITTP). The incidence has been as low as one in 50,000 (0.002 per cent), but in a large population, the numbers become significant.

Dr. Rajeev Jayadevan, co-chairman of the Indian Medical Association’s National Covid-19 Task Force, stated that TTS is a very rare condition resulting from an abnormal immune response and has been linked with adenovirus vector vaccines, which was also mentioned in a report published by the WHO on May 27, 2021. In the UK, the pharmaceutical company AstraZeneca has admitted in court documents for the first time that its Covid vaccine can cause a rare blood clot risk.

The company has accepted in a legal document submitted to the High Court that its Covid vaccine ‘can, in very rare cases, cause TTS’. About 51 cases have been lodged in the UK High Court against the pharmaceutical giant over claims that its Covid vaccine caused death and serious injury, with victims and grieving relatives seeking substantial damages.

In India, almost 90 per cent of people who received the Covid vaccine received the AstraZeneca vaccine known as Covishield, which is made from a harmless cold virus linked to chimpanzees. Dr. Ishwar explained the mechanism of potential TTS risk and addressed concerns about the safety of the Covishield vaccine, emphasizing that the benefits of Covid vaccines far outweigh the risks.

Dr. Rajeev added that vaccinated individuals have a lower overall risk of death from Covid and complications associated with post-Covid heart attacks and strokes. He stated that although there are extremely rare serious side effects associated with vaccines, the benefits have prevented hundreds of thousands of deaths from Covid.