CHENNAI: A serosurvey for Covid-19 conducted by the Directorate of Public Health (DPH) and Preventive Medicine among elderly people in six districts of Tamil Nadu in the month of April has shown 97% of the surveyed population to have protective levels of immunity.
The results showing high seroprevalence of SARS CoV-2 IgG antibodies, coming amid concerns of a surge in number of Covid-19 cases, showed that the infections by SARS CoV-2 virus could not cause severe illness, the health department said. It added that deaths due to Covid-19 are almost nil in TN.
According to the DPH, a total of 3,643 blood samples were collected from persons as part of the elderly panel survey in Chennai, Tiruvallur, Tiruvannamalai, Tiruchy, Dharmapuri and Kanniyakumari districts.
“Preliminary analysis of 1,214 samples tested for SARS-CoV antibodies (IgG) showed the protective levels of immunity to be 97%,” a DPH release said.
The press release said that even after a gap of three years in conducting the present Phase V of the serosurvey, the prevalence of protective level of SARS CoV antibodies is very high and significant.
Effective vaccination drives implemented by the state government might be responsible for the high level of protection against SARS CoV-2 virus, it said.
“In addition, natural infection and subclinical infection due to the weakened circulating Omicron sub lineage of SARS CoV-2 virus could have also enhanced the development of antibodies,” the release added. The state has not officially released data on Covid-19 cases after the recent surge across the country.
‘Only Omicron variants which are not virulent are found in the state’
The data put out by the Union Health Ministry, however, showed that Tamil Nadu had 204 active Covid-19 cases and six persons who tested positive had died. Meanwhile, State Health Minister Ma Subramanian told reporters that people need not panic about Covid-19.
The DPH sent 19 samples from the state to the Institute of Virology, Pune, for testing, and it found only Omicron variants which are not virulent. It has been advised that elderly people, immunity compromised people, pregnant mothers, and people with comorbidities should wear face masks when gathering in public places.
People infected with Covid experience symptoms like cough, cold, and fever and may become normal within three days. The district health team is monitoring them, the minister added.