Covid-19: One-fifth of Chennai population is exposed to SARS-CoV-2 infection, sero survey finds

CHENNAI: One-fifth of the population of Chennai has been exposed to SARS-CoV-2 infection, according to a seroprevalence survey done in the city.
"Around 80% of the population is still susceptible to SARS-CoV-2 infection in Chennai," the report said. The survey report was released by the Greater Chennai Corporation on Tuesday.
The sero survey is a blood test done on individuals to check the presence of antibodies.
Around 21.5% from a sample of 12,405 people in the city had evidence of past SARS-CoV-2 or Covid-19 infection, the survey found.
The GCC said blood samples of 12,405 individuals from 51 wards covering all the 15 zones were collected.
A huge variation was seen in seroprevalence across zones, the report said. For instance, this figure was 7.1% in Madhavaram and 44.2% in Tondiarpet.