Signs of herd immunity in Delhi? Up to 60% population infected with COVID-19

Delhi finished its fifth serosurvey to assess the spread of coronavirus infection in the national capital. The result of the serosurvey discovered that at least 50-60 per cent of the city's population has developed antibodies against coronavirus. This means that they were at some point infected unwittingly with coronavirus and were cured later.

Delhi has a population of more than 2 crore and about half its population was infected at one point and developed antibodies as per the fifth round of serosurvey. The official count of infections is 6.34 lakh.

As a result, the 5th serosurvey has indicated that Delhi's population could be heading towards herd immunity. That's because herd immunity against coronavirus is formed when 50-60 per cent of the population found to have the presence of antibodies.

Herd immunity means that in any set of people in a community, large portions of people become immune to a virus after getting infected due to the antibodies developed. And, hence, such people become a protective layer between the infected person and unaffected people, thereby breaking the chain of viral transmission.

In the latest serosurvey, health officials took blood samples of 25,000 people from various districts across the city to analyse how the COVID-19 virus spread and its implications in the city's population. The fifth serosurvey was conducted from January 10 to January 23.

Previously, the Delhi government in association with the National Centre for Disease Control (NCDC) had conducted four rounds of serosurveys. The first happened between June 27 and July 10 in 2020 in which 21,387 samples were tested and found that around 23 per cent of the people surveyed had exposure to the novel coronavirus.

The exercise in August showed 29.1 per cent of people had antibodies. In the survey in September and October, the figures stood at 25.1 per cent and 25.5 per cent in October.

Delhi recorded 148 fresh COVID-19 cases on Monday, the lowest in nine months, even as the positivity rate stood at 0.31 per cent.

This is also the fourth time, the number of daily cases has stood below the 200-mark in January. So far, 10,813 have died due to COVID-19 in the capital.

Also read: PM Modi greets Indians on 72nd Republic Day

Also read: India bans TikTok permanently; app evaluates notice