‘97% of surveyed people have antibodies against COVID-19’

Blood samples were collected as part of serosurvey in Sept.

As many as 97% of the 28,000 people, whose blood samples were collected in September from across the city, have developed antibodies against COVID-19, according to authorities.

Blood samples of random people of different age groups were collected as part of a serological survey to check how many of them had developed antibodies against the virus.

Higher in women

“The survey was done in 280 wards of Delhi. At least 100 samples from each ward were collected. The government collected 28,000 samples of random people. Sero prevalence was higher in women [90.1%] as compared to men with only [88.2%] positivity. Serosurvey was conducted in all the 11 districts of the national capital and the data showed that 97% of people had antibodies against COVID-19,” Health Minister Satyendar Jain said.

He said that all districts showed a value of above 95% and almost all vaccinated people had developed antibodies. The Minister said the survey showed that the population with a past history of symptomatic COVID-19 infection, irrespective of severity, had significantly higher odds of having antibodies compared to those without such history.

Of the people surveyed, 95.3%, who had taken both the doses of Covishield, had developed antibodies. For Covaxin, the figure stood at 93%. Similarly, 95.6% of people who had taken one dose of Covishield had antibodies. It was 92.1% for Covaxin.

What is a sero survey?

Blood samples collected from across the city are tested in a lab using antibody testing kits to understand whether the person was infected by the virus and developed antibodies.

A positive result would imply that the person has developed antibodies. This means that the person was infected at some point and developed immunity against the virus or has developed antibodies after vaccination.

The first such survey done in the city in June-July last year had shown that 23.4% people surveyed had developed antibodies. Similar surveys in August 2020 showed that 29.1% people have antibodies, 25.1% in September 2020, 25.5% in October, and 56.13% in January.