Sample collection for 2nd sero survey ends

NEW DELHI: Collection of blood samples for the second round of serological surveillance in Delhi was completed on Friday, with administrations of the city’s 11 districts collecting samples from just over 15,000 people, intended to be representative of the Capital’s population.

The results of the survey are expected early next week, officials said.

“Results will be processed by a team at Maulana Azad Medical College, and are likely to be released by next week,” Delhi health department officials said.

The survey will indicate what percentage of the city’s population has developed antibodies against the Sars-cov-2 virus, which causes Covid-19, since the first such survey was conducted between June 27 and July 10. Of those surveyed in that instance, 22.6% had antibodies against the infection.

The highest number of samples were collected from Northwest district, followed by West, and Central.

“We have been reporting new cases of the infection since the previous sero-surveillance, meaning that the proportion of people who have the antibodies are likely to be higher this time around. If 30 to 60% of the population has the antibodies, it will show that Delhi is on its way to developing herd immunity,” said a doctor from central district.

Herd immunity is said to have been achieved when a significant proportion of the population has developed resistance to an infection, preventing further spread.

“In the month since Delhi’s first survey, I am expecting that the prevalence of antibodies must have gone up to about 40%,” said Dr Jugal Kishore, head of the department of community medicine at Safdarjung hospital.