The most reliable longer-term protection against coronavirus is provided through vaccination, experts said on Monday noting that the immunity afforded by the presence of antibodies might be expected to last only several months. The experts -- Rajeeva Karandikar from the Chennai Mathematical Institute; Shekhar Mande, Director General, CSIR; and M Vidyasagar from IIT Hyderabad -- said it is crucial to ensure that the number of cases does not start increasing again as it has in many countries such as Italy, the UK, and the USA.
They said according to both serological surveys as well as model predictions, a substantial fraction of India's population currently has immunity against the virus, coupled perhaps with some natural form of immunity.
“Although the current evidence is suggestive of long-lasting immune memory, the immunity afforded by the presence of antibodies might be expected to last for only several months and not longer, while T-cell mediated immunity might last longer. The most reliable longer-term protection is, however, provided through vaccination,” they said in a statement.
They added that it has been suggested recently that vaccination offers a much stronger immune response than natural infection, and therefore is the key to controlling the spread of the disease.
“While this issue has not yet been settled decisively, some medical researchers are of the opinion that the presence of antibodies (caused by a previous infection) offers less protection against reinfection from a mutation of the virus, compared to vaccination,” they said.
Hence, it is imperative that the nationwide vaccination programme be completed as early as possible with the approved vaccines.