For the first time, AstraZeneca acknowledged that a rare adverse effect known as TTS could result from its vaccination.
Low blood platelet counts and blood clots are two symptoms of TTS.
Usually, the condition’s symptoms appear 4 to 42 days following vaccination.
British drugmaker AstraZeneca has admitted for the first time in court documents that its vaccine against Covid-19 is likely to cause TTS, a rare side effect associated with blood clots. TTS or Thrombosis with Thrombocytopenia Syndrome causes blood clots and a reduced number of platelets in the blood.
The company is facing 51 lawsuits claiming its vaccine caused death and serious injury in dozens of cases. The news has affected millions of people across the world, including those in India, where the vaccine was rolled out to reduce severe complications of Covid-19 under the brand name Covishield.
Should you be worried?
India Today spoke to doctors about AstraZeneca’s admission and the rare side effect caused by its Covid-19 vaccine. Dr Sudhir Kumar, neurologist at Apollo Hospitals in Hyderabad, said, “Vaccination-related adverse effects usually occur within a few weeks (1-6 weeks) of administration.
Therefore, people in India who have taken the vaccine 2 years ago need not worry.” Dr Rajeev Jayadevan, co-president of the National Indian Medical Association, said this particular outcome is reported only in the first month after the first dose, not after that.
In India, Dr Kumar said the incidence of TTS after vaccines is not known. “Only isolated cases have been reported. Therefore, TTP after Covid vaccination is extremely rare, considering that millions of vaccines have been administered,” the expert said. The expert said these revelations are not new. In fact, isolated cases of TTS from different parts of the world after Covid-19 vaccination have been published since 2021.
“TTS has been a well-known and recognised disease for the last 100 years, as its first case was reported in 1924 by Eli Moshkowitz in a 16-year-old girl. The underlying mechanisms of TTP have been known since 1982, and have been part of the medical curriculum during the last 4 decades,” Dr Kumar said.
Though Covid vaccines do increase the risk of blood clots, the risk is very low.
“This has been proven in several scientific studies published from India and other countries. For the record, Covid infection increases the risk of blood clots, much more than Covid vaccines,” Dr Kumar said.
Dr Jayadevan said Covid-19 itself is an established cause of clots, heart attacks and strokes, and people who are vaccinated have a lower risk of these outcomes.
Is Covaxin better than Covishield?
Dr Kumar said there is not enough data to help us choose one Covid vaccine over another based on the risk of adverse effects.
“Also, TTS has been reported with other vaccines such as influenza vaccine, pneumococcal vaccine, H1N1 vaccination and rabies vaccine,” Dr Kumar said.
Dr Jayadevan said both vaccines are effective.
“There is nothing that says one is better than the other. All vaccines and medical treatments have side effects. Crores of people who have taken these vaccines in India are now alive and well,” he said.
What are the side effects of AstraZeneca?
Rare side effects associated with adenovirus vaccines such as AstraZeneca’s and Johnson’s Janssen’s can include Guillain Barre syndrome (which causes paralysis of the hands and feet), Bell’s palsy (causes facial weakness), stroke, cerebral venous sinus thrombosis and heart attacks.
The AstraZeneca vaccine was halted in various countries after a rare side effect of blood clots was reported
