BENGALURU: The state’s first plasma bank was inaugurated at HCG Hospital on July 21, and soon after, 147 donors came forward to donate their plasma. But many of them do not have the required immunity levels, or IgG (Immunoglobulin G) antibodies, which does not allow them to donate the plasma. But more worryingly, these cured patients could be open to a Covid infection again because of their low immunity levels to the virus.
IgG develops 14 days after the infection and keeps increasing for more than six months to a year and more. It prevents repeat infection of a particular disease. Dr Niveditha Jayaram, Laboratory Director, Streamed Life Sciences, HCG Hospital, said, “When Covid infects a person, between the fifth and seventh day of infection, the body develops its first line of defence - IgM antibodies.
It peaks and comes down by the 21 day. Meanwhile, on the 14th day, IgG comes into play and titres of IgG keep increasing and will remain in the body for a long time. But in these recovered patients, the IgG is disappearing soon and they are open to reinfection.” Dr Vishal Rao, Associate Dean, Centre for Academics and Research, HCG Cancer Hospital, and a member of the Covid consultative group, said, “We found that a few recovered patients who had come to donate plasma did not have the antibodies, which was an eye-opener for us.
Our immunology team is now checking as to why these patients are not developing IgG.” Dr Niveditha said that they have checked all healthy, recovered patients in the age group of 20-30 years who have not shown the required IgG levels. “It does not look like a natural virus, as it is behaving differently from one person to another. We have seen patients with good amounts of antibodies and we ask them to report back after four weeks to donate the plasma.
But when they come back, we see that their antibodies counts are low, which is surprising. They cannot donate their plasma as it does not help the other individual.” She said, “A vaccination may help to a certain extent, but we don’t know how long long it protects us.” Dr Sachin Jadhav, Group Head of Haematology and Bone Marrow Transplant, HCG, said that across the world, nearly 80% of recovered patients have not generated required quantities of antibodies, and it should not be a cause for concern. “Many have been reinfected as well. We don’t have the neutralising antibody titre test in our country that can exactly check patients who have antibodies,” he said.