70% Of Tamil Nadu Population Exposed To Coronavirus, Reveals Sero Survey

Directorate of public health and preventive medicine has taken up the third phase of serosurvey between July and August, 2021. As many as 24,586 samples from 827 clusters were included in the survey.

Chennai: The third phase of the state-wide cross-sectional seroprevalence re-survey has revealed that about 70% of Tamil Nadu’s population has been exposed to SARS-CoV-2. 

The state government’s directorate of public health and preventive medicine has taken up the third phase of serosurvey between July and August, 2021. As many as 24,586 samples from 827 clusters were included in the survey. Of which, 17,090 individuals had antibodies against the virus causing Covid-19 (SARS-CoV-2), according to a report in the Hindu. 

The data that was first released in July revealed that about 66.2% of the population had been exposed to SARS-CoV-2. The department released the findings of the re-survey on Thursday. 

The report said that districts like Virudhunagar, Tenkasi and Chennai have more than 80% seropositivity which is higher than the state’s seropositivity and districts like Ariyalur, Nilgiris, Karur and Perambalur has less than 60% seropositivity. 

Quoting TS Selvavinayagam, director of public health and preventive medicine, the report said that they had re-surveyed five districts in each upper and lower limits to reconfirm the findings and their results were in confirmation with the latest Indian Council of Medical Research Survey. 

The seropositivity of Virudhunagar has increased from 84% to 88% following the re-survey and the district tops the list. It is followed by Tenkasi district with 83% seropositivity, Chennai with 82% seropositivity, Madurai with 79% seropositivity and Theni with 76% seropositivity. 

According to the report, the seropositivity rate has gone up in some of the western districts. The seropositivity of Erode has gone up from 37% to 70%, Coimbatore has gone up from 43% to 71% and Tirupur has gone up from 46% to 70%. The increase in seropositivity rate has been attributed to rise in exposure to the infection and speeding up of vaccination process.

The state was moving towards a safer zone and the vaccination drives had been helping us, the director said as per the report.