COVID-19 antibodies won't last beyond 2-3 months, say experts

New Delhi: As a few cases of re-infection have emerged in India and around the world; while most have been ruled out citing false-negative tests, medical experts in Delhi have not completely ruled out the possibility, saying some of the cases could be attributed to COVID-19 antibodies waning off a couple of months after recovery.

Speaking to Millennium Post, Dr Puneet Khanna Head of Respiratory Medicine at Manipal Hospital said that after three months of recovery, the number of antibodies starts declining, affirming that recovered COVID-19 patients do not have long-lasting antibodies as per data available at the time.

"In one case, the person had tested positive, however, had then tested negative. They were later readmitted in a small time span, and were tested positive again," Dr Khanna said, adding that there is a possibility of false-negative reports as well.

Neutralising antibodies generated in response to the Coronavirus infection will last for two to three months but not beyond that, according to medical experts.

"There are two kinds of antibodies, one is neutralising antibodies and the other is non-neutralising antibodies. Whenever we have an infection, there is a response in the body where both these antibodies are formed. It also depends on the amount of infection one gets. If the amount of infection is high then there is a chance the person will have a higher amount of neutralising antibodies," Dr Khanna added.

Dr Gagan Srivastava, Senior Consultant, Cardiac Anesthesia at Fortis Hospital said that Delhi has witnessed re-infection cases, but the numbers are very low to determine anything. It is to be noted that, since Delhi saw a surge in cases from April and May, the cases of re-infection have not been as high.

"The re-infection cases that have come, as of now, are not very severe. Most of the cases depend on the viral load.

If you get a low viral load, it may act as a vaccine for you.

But the viral load that infects you cannot be calculated in the first go. So, you do not know whether it is a lethal dose," Dr Srivastava said.

However, the death of a Delhi Police personnel in July, who was reportedly re-infected and died due to COVID-19, after he had resumed his duties, had confused doctors. "There are cases where the person can get infected before two to three months after recovering. There is a case where a person got re-infected within the span of 15 days, where the COVID-19 report was again positive," one doctor added.

A senior official at All India Institute of Medical Science (AIIMS) had said that the possibility of re-infection of cases might not be too far away for Delhi. "We have seen a few re-infection cases, the number is very low at the moment. But if we see the reports by the international community, then it is guaranteed that antibodies will wane within three months and the possibility of re-infection emerges," he said.