Single Dose Enough For Covid-Survivors: ICMR

Until a few days ago, the new Delta Plus variant, which has been formed due to a mutation in the Delta or B.1.617.2 variant, was not a concern due to low incidence. But the rapid increase in the severity of the disease due to the new variant has once again left all of us to where it started.

The Indian Council of Medical Research (ICMR) conducted research and came to a conclusion that all covid-19 survivors who have received one or both doses of vaccine exhibit higher protection against the Delta variant when compared to those who have taken one or two doses of Covishield.

The new study is based on how the humoral and cellular immune response is playing a pivotal role in protection against the Delta variant. The new variant has increased transmissibility and virulence than other mutated strains so far. “Prior vaccination results in less severe disease against subsequent infection provide evidence that both humoral and cellular immune response plays an important role in protection,” the ICMR report stated.

The research suggests that even one dose of vaccine in a Covid-recovered patient is sufficient to protect against a coronavirus re-infection and can also shield an individual against new variants. This is because the survivors will have a high neutralizing antibody count.

The vaccines that are present in the market are also said to have given rise to robust humoral and cellular immune responses against the coronavirus. However, in the Delta variant infecting people, even after two shots of Covid-19 vaccines, it is “crucial to continuously evaluate vaccine-induced humoral immunity to SARS-CoV-2, immunity following natural infection, and the phenomenon of breakthrough infection to understand the immune escape” due to emerging variants of concern (VOCs).

The Delta Plus variant of Covid-19 is the sub-lineage of the highly transmissible Delta variant that was a major contributor to the second wave of infections. The Health Ministry categorised the Delta Plus variant or B.1.617.2.1 of the coronavirus as a Variant of Concern (VOC) and directed states to take up immediate containment measures. Currently, India reported more than 60 Delta Plus cases and this worries it would trigger another wave of infections in the country.