Delta variant: People administered Covishield may need third dose, says ICMR

The delta variant of the coronavirus is likely to cause a third wave. The antibody produced from the vaccine has been shown to rapidly deplete the delta strain. In a study conducted by ICMR, people who took Covishield are becoming infected with the Delta Corona virus. This weakens the antibodies produced in their body. Researchers are advising that these people be given a third dose.

The Delta variant reduces the antibody made from the first dose of Covishield by 4.5 times and the antibody made from the second dose by 3.2 times compared to the older viruses of the D614G mutation. Dr Samiran Panda, Head of Epidemiology and Infection, ICMR, said that this type of information would help in deciding the strategy of the vaccination campaign. 

According to a study by ICMR, people who were infected with covid, the virus acted as the first dose of vaccine. People who took two doses after being infected with covid produced antibodies only three times. Similarly, those who were not infected with covid and took one or two doses of Covishield and later got infected, were found to produce large amounts of antibodies, Panda said.

However, people who have taken two doses of Covishield and have not had a corona infection before or after taking it will need to take a third dose. Only then will they produce as many antibodies as people who have been exposed to antibodies three times, Panda said. Dr. Yadav said that for those who were recently infected with covid, a single dose of vaccine is sufficient for them. But in people who have never been infected, Covishield has developed antibodies. However, few people develop antibodies after vaccination.