Researchers also said there was evidence that some recovered patients of covid-19 have waning antibody level after few months. While India has large number of recovered covid-19 patients, the country might have to think vaccinating them as well. There is little information about the virus and longevity of the immunity after its infection or reinfection is not known. Initial vaccine related studies show the vaccine produced antibodies and killer T-cells to combat the infection. “Whole dead virus vaccine possibly cover all strains but mutated strains keep coming then every time new vaccine required beside old one like flu vaccine," said Jugal Kishore, professor and head, department of community medicine, Safdarjung Hospital.

Source: Mint August 25, 2020 09:56 UTC