About 54% of the population in Hyderabad and Secunderabad within the Greater Hyderabad Municipal Corporation (GHMC) limits have been found to be having antibodies against coronavirus in a latest sero-surveillance survey conducted by city-based scientific institutions.
The study conducted jointly by the Centre for Cellular and Molecular Biology (CCMB), National Institute of Nutrition (NIN) and Bharat Biotech International Limited (BBIL) on a sample size of about 9,000 participants, all of them older than 10 years, has indicated that half the population has either been infected or exposed to coronavirus.
“It is very exciting as we could be near the end of this pandemic. We have reached a critical stage of infection among the population. This is the right time to go for vaccination when the infection transmission is weak and there are no cases of re-infection. This could take the antibodies prevalence among the population to 75-80% when the herd immunity may kick in,” said CCMB Director Rakesh Mishra at a press conference on Thursday.
Data generated in the latest seroprevalence study appeared to be robust considering there was not much variation in each of the divisions and a similar study done in the sewage systems for the prevalence of coronavirus among the population pointed out towards the same figure.
The above 10 years age group, chosen as the segment, have been venturing out and from the data, it was clear that the older generation between 70-90 years had less antibodies because either they were “well-protected or have had asymptomatic infection”.
The Director reiterated that both vaccines cleared by government regulatory authorities were safe and people should not hesitate to vaccinate themselves when their slot is determined as it would only strengthen the immune response of the body. “Vaccine will help the body fight the infection better, but it may not prevent us from getting infected and we in turn could infect others,” he cautioned.
Dr. Mishra also emphasised the need to continue to adhere to the ‘social vaccine’ of face masking, avoiding indoor crowded meetings, hand washing and personal hygiene as the virus is “around in the air” and live cases across the country are more than a lakh.
As things stand now, natural immunity due to COVID infection could last up to six months in most cases while the vaccine efficacy is about a year. Even later, it is possible that the body’s immune memory system could handle any new infection unless its a potent mutant variant, he said.
Senior NIN scientist K. Laxmaiah said that data shows infection spread is ‘even’ among all age groups, communities and localities too. For the latest study, 75 personnel were involved to test 300 people from 30 divisions.
A follow up study on COVID-19 infected patients had shown that the antibodies rise within a month of infection, increase till the fifth month and reduce after the sixth month. BBIL’s Krishna Mohan said these kind of epidemiological studies are crucial for vaccine-makers for any infectious disease and the latest study shows a consistent pattern of development of antibodies among the population.
