AstraZeneca’s recent acknowledgement that, in extremely rare circumstances the Covishield vaccine may result in thrombotic thrombocytopenia syndrome (TTS) created a fear among public and resulted in a political slugfest by some politicians saying that many healthy youngster who had taken the Covid vaccines are getting heart attack. The acknowledgement was made in court documents related to a case alleging that the vaccine resulted in death and serious injury in numerous instances.

Dr. CN Manjunath, former director of the Jayadeva Institute of Cardiology and an ex-member of the state-level Technical Advisory Committee, said that in 2021, the Covishield prevalent concerns were due to reports linking it to instances of blood clots and rare-occurrences of brain and heart strokes.

He further said that as a medical professional it is important to approach such findings with a balanced perspective by carefully evaluating the benefits and potential risks associated with any vaccine or medication. One of the fundamental principles in medicine is the concept of risk-benefit analysis. This principle is very crucial in the case of vaccines, where the goal is to provide protection against infectious diseases without compromising overall health. In the initial wave of the pandemic, we witnessed tragic loss of lives. However, in the subsequent time, there was a noticeable decline in the fatal cases due to widespread administration of vaccines and their proven efficacy in reducing severe illness and mortality rates. It is relevant to highlight that significant side effects manifest within a relatively short period, usually within six months to a year following vaccination.  Over 80 crore people in India received vaccines, any major concerns related to adverse effects would have been surfaced and thoroughly evaluated by health authorities. 

He also added that the prevalence of cardiac issues in India with approximately 30 lakh people existed prior to the pandemic and are not indicative of an increase in heart problems caused by Covid vaccines. Therefore, attributing rising cases solely to vaccination would be a misinterpretation of the broader health landscape. Individuals who have received Covishield vaccines need not be concerned about side effects at present, as these vaccines were administered a couple of years ago.

What is Thrombosis with Thrombocytopenia Syndrome?

TTS is a severe health condition associated with adenovirus vector vaccines, including Covishield. TTS leads to low platelet count (thrombocytopenia) and the formation of blood clots (thrombosis) within the body. AstraZeneca has now announced the global withdrawal of the vaccine on May 7, 2014 marketed under brand names Covishield and Vaxzevria, developed in collaboration with the University of Oxford. Another reason is the availability of a plethora of new shots that has led to a decline in demand.

What is the main reason for Covishield withdrawal?

Many millions have had the vaccine without suffering complications but in 2021, the Medicines and Healthcare Products Regulatory Agency (MHRA) confirmed a possible link between the vaccine, known as Vaxzevria, and a rare condition involving blood clots along with abnormally low platelet levels. MHRA is an executive agency of the Department of Health and Social Care in the United Kingdom, which is responsible for ensuring that medicines and medical devices work and are acceptably safe.

What is the standing of Serum Institute of India (SII)?

Amid the ongoing concerns regarding the side effects of Covishield vaccine, Serum Institute of India on Wednesday disclosed that it had stopped manufacturing the vaccine and supply of additional doses in December 2021 itself. SII also said that it had disclosed all rare and very rare side effects of the vaccine in the packaging inserts as well.