The national committee on serious adverse events following immunisation (AEFI) has found a few cases of blood clots associated with post-Covishield vaccination in India. India has reported only 0.61 cases of deep vein thrombosis or blood clots per 1 million doses of Covishield vaccine, sources have said.
Most of the blood clot cases following immunization have been seen till the first week after vaccination “This is very less if compared with that reported in the United Kingdom; vaccination outweighs the risk,” a source, aware of the development in the government, said.
“Bleeding and clotting cases following Covid vaccination in India are minuscule and in line with the expected number of diagnoses of these conditions in the country,” a report submitted by the National AEFI (Adverse Event Following Immunization) Committee to the Ministry of Health & Family Welfare said in a statement issued.
The AEFI committee has completed an in-depth case review of 498 serious and severe events, of which 26 cases have been reported to be potential thromboembolic (formation of a clot in a blood vessel that might also break loose and carried by the blood stream to plug another vessel) events following the administration of Covishield vaccine with a reporting rate of 0.61 cases/ million doses.
There were no potential thromboembolic events reported following the administration of the Covaxin vaccine, the statement said.
“Data analysed by the government panel also suggests that South Asians may genetically have less propensity to develop thrombosis or clotting post-vaccination as compared with those in western countries,” sources in the national committee tracking adverse events following immunisation said.
The national AEFI committee noted that as of April 3, 75,435,381 vaccine doses had been administered (Covishield 68,650,819; Covaxin 6,784,562). Of these, 65,944,106 were first doses and 9,491,275 second dose.
Since the Covid-19 vaccination drive was initiated more than 23,000 adverse events were reported through the CO-WIN platform from 684 of the 753 districts of the country. Of these, only 700 cases (@9.3 cases/million doses administered) were reported to be serious and severe in nature, the statement mentioned.
AEFI data in India showed that there is a very minuscule but definitive risk of thromboembolic events. The reporting rate of these events in India is around 0.61/million doses, which is much lower than the 4 cases/million reported by UK’s regulator Medical and Health Regulatory Authority (MHRA).
“It is important to know that thromboembolic events keep occurring in the general population as background and scientific literature suggests that this risk is almost 70 per cent less in persons of South and South East Asian descent in comparison to those from European descent,” says the union health ministry.
Covaxin has not been associated or linked with any blood clotting events in India yet, the sources said. The government could issue an advisory if such cases are reported within 28 days.
“People must watch out for symptoms such as severe headaches, seizures, vomiting, pain in the stomach, and breathlessness post taking Covishield,” the source said.
To date, India has reviewed over 700 adverse events following immunisation. According to a presentation made to the National AEFI Committee, during a meeting held on March 31, there have been 617 severe and serious (including deaths) adverse events following immunisation (AEFI).
As of March 29, a total of 180 deaths (29.2%) have been reported following vaccinations across the country. Complete documentation is available only for 236 (38.3%) cases.