After India discussed its COVID-19 vaccination plans and shared its priority list for vaccinating 30 crore citizens, questions have emerged if the almost 9.3 million Indians who have recovered from COVID-19 should be vaccinated. There are no specific government guidelines either that exclude those infected from being vaccinated.
While it is known that patients who recover from COVID-19 develop neutralising antibodies against SARS-CoV-2, the duration for which the immunity lasts is still being examined and debated. Although reinfection is rare, there have been cases of reinfection reported across the world. The reinfection is due to a mutation in the D614G gene in the spike protein of SARS-CoV-2.
However, Health Secretary Rajesh Bhushan and Indian Council of Medical Research (ICMR), Director General Dr Balrama Bhargava did state during a press briefing on December 1 that participants who have already been infected could receive the vaccine.
"There are two important issues linked with the immunisation of such a set of people. If someone has antibodies against the COVID-19 infection, and a vaccine is given to that person, would he or she develop any vaccine-associated adverse reaction? Secondly, if we consider the presence of antibodies and avoid the administration of vaccines to the person, would we be able to spare our vaccine doses?" Bhargava stated.
Currently, the World Health Organisation has not released any mandate stating that the people who have already been infected should be excluded from the COVID-19 vaccination drive.
Experts Divided On COVID-19 Vaccine For The Already Infected
An article on Inside Science highlighted that vaccines could serve as a better alternative to natural infection for inducing COVID-19 immunity. Studies across the world have showed various impairments in memory B cells and killer T cells, that form the body's immune response. The B cells identify the SARS-CoV-2 as a prior infection and the T cells than attack the pathogen.
Long lasting immunity of COVID-19 is still being disputed as the virus is still new in the medical world. Cases of reinfection have emerged across the world.
Experts however, are divided on whether the COVID-19 Vaccine should be administered to the ones who have recovered after being infected.
"If it was not a pandemic situation, and stocks were not limited, I would have said vaccinate the already infected," said Dr. Vineeta Bal, immunologist from IISER Pune. "Theoretically, there is no harm to give vaccine to the already infected and recovered, but when the vaccine will be available, there will be a shortage."
Bal further added that the already infected who are a part of the high priority groups can be vaccinated six months down the line once the availability of the vaccine is more streamlined. Till then, they should be at the lower rung of the high priority list too.
Dr Shahid Jameel, virologist and Director of the Trivedi School of Biosciences, Ashoka University thinks otherwise. He believes that the vaccine is unlikely to give better immunity than natural infection. "However, since a vast majority of infections are asymptomatic, testing to find out who got infected adds another layer of cost and logistics. Therefore, not worth it. Give the vaccine to everyone who is eligible and on priority," added Dr. Jameel.
So far, only the vaccine for the Human Papilloma Virus which causes cervical cancer is known to provide immunity better than natural infection.
The Centres for Diseases Control and Prevention, US, has found that serum antibodies were seen to wane about two months after infection. Long-lasting immunity of the antibodies needs to be further researched.
