29% Of Delhi Has COVID-19 Antibodies, Finds Second Sero Survey

The study was conducted over a 12-14 day period in the first half of July. Participants were from slum and non-slum areas.

(Photo: PTI)

The second sero survey in Delhi has found that 29.1 percent of the people studied in the national capital from 1-7 August have developed antibodies against the novel coronavirus, an increase from the 23.48 percent found in the first such survey conducted from 27 June to 10 July.

The survey was planned by the Delhi government with technical support of the Maulana Azad Medical College.

Announcing the results on Thursday, 20 August, Health Minister Satyendar Jain said:

“The second serological survey, which was conducted between 1-7 August, shows that 29.1 percent of people have developed antibodies against COVID-19. A total of 15,000 samples were collected during the survey.”

Health Minister Satyendar Jain

The survey was conducted in all 11 districts of the state, and the highest prevalence was found in Southeast Delhi at 33.2 percent. Out of the total samples collected, half were from people between the ages of 18 and 49. The seroprevalence was higher in females at 32.2 percent than in males (28.3 percent).

The other two rounds are scheduled in the first weeks of September and October.

What Are Serosurveys?

It’s important to note that antibody tests are not diagnostic tests but are used to check the prevalence of the infection in the general population. These surveys, at best, indicate the possible spread of the disease in the community and help authorities come up with better strategies.

They show us the presence or absence of antibodies in a person – they do not tell us the amount, and they cannot identify if these are ‘neutralising’ antibodies (which specifically target the pathogen in concern).

Associating the presence of antibodies to immunity against COVID-19 is another overstretched link, experts believe. FIT had earlier reported on the dangers of assuming herd immunity based on sero survey results.

A significant portion of the population remains vulnerable, and precautions will have to be continued to be observed, including hand hygiene, masks and physical distancing, besides containment measures.

(The article was first published in FIT and has been republished with permission.)