2,500 more samples collected on second day of sero survey in Delhi

NEW DELHI: On the second day of the monthly serological survey started by Delhi government in the capital, total 2,500 samples were collected from at least eight revenue districts on Sunday, sources said. As many as 1,500 samples were collected on Saturday.


The first serological survey conducted between June-end and first week of July in Delhi had revealed the presence of Covid-19 antibodies in around 24% of the total 21,387 samples collected. After the survey results were declared, Delhi health minister Satyendar Jain had announced that a sero survey would be carried out in the city in the first week of every month to determine the actual spread of the novel coronavirus and the government believes that the result of the second round of sero survey will show around 35% prevalence of antibodies in samples.

“On Saturday, the survey started from four districts and on Sunday, samples were collected from eight districts. The survey will gather more pace Monday onwards,” an official said.

“For the first sero survey, teams comprising health workers had visited different areas and chosen every fifth house from a selected locality. For this survey, however, we are selecting residents of the identified locations through a randomised sampling technique and asking them to visit their nearest dispensary,” he said.

Officials said that for the first sero survey, teams of health workers had to visit door-to-door and the team members collecting blood samples had to wear PPE kits, which made working in the heat very difficult. “We had to take rest after every couple of house as wearing a PPE kit even in room temperature makes you claustrophobic and wearing it in such humid conditions completely drains you out,” the official said.

All 11 districts have to collect around 15,000 samples, which is less than the number of samples collected in the first round of survey. However, officials said that the sampling is being done very scientifically and is completely randomised and uniform, with proportionate samples being taken from each group, such as 25% samples from those below 18 years of age. The exercise is crucial to find out if Delhi is heading towards herd immunity from the coronavirus.