BMC to do qualitative study of Covid-19 antibodies

A young woman gets the jab during a vaccination drive at BYL Nair Hospital on Saturday. Pic/Ashish Raje

Unlike earlier sero-surveys, where only the presence or absence of Covid-19 antibodies was detected, this time the BMC will conduct a qualitative check of antibodies to reveal the level of protection after months of vaccination. This will give result of long-term impact of vaccines and help improve vaccination programmes.

The BMC had planned to conduct a regular sero-survey of 10,000 samples in January, but as the third wave hit the city, it was postponed. Now, with the third wave receding and no new scare in sight, the corporation has planned a year-long sero-survey of healthcare and frontline workers to see the level of antibodies, six and nine months after taking the vaccine. After a Coronavirus infection or a vaccination, the body produces antibodies against the virus's spike protein. Unlike older antibody tests, which simply detect whether antibodies are present or not, new tests can tell the level of antibodies in the blood.

As per the plan, the BMC will collect 3,000 samples of healthcare and frontline workers from the next month. The sample selection will be random - it can be from fully vaccinated, or with or without the precautionary booster dose. Then samples from the same persons will be taken after a gap of six and nine months. "We will be able to get the level of antibodies on day 1, and after six and nine months. In the earlier sero surveys, our aim was only to find prevalence of the virus among communities. With the new survey, we will be able to understand the impact of vaccination over longer duration and it will help with our future vaccination programmes," said Suresh Kakani, additional commissioner of the BMC. The last, fifth sero-survey, conducted in August, revealed that 87 per cent of people had antibodies.

3,000
No. of samples that the BMC will be collecting for the survey