A second serological survey in Chennai has found that one-third of the city’s population has been exposed to the coronavirus and has thus developed antibodies for the infection, India Today reported on Friday.
Out of 6,389 samples tested in the second sero survey, 2,062 were positive for Covid-19 antibodies, showing an overall positivity rate of 32.3% in the city, according to the Greater Chennai Corporation.
G Prakash, Greater Chennai Corporation commissioner, told India Today that the sero survey has shown a positive trend, while also stressing that people should continue to take precautions. “This is a positive trend, but we shouldn’t let our guard down,” he said. “This means for the next three months, we have to continue the precautions which are in place.”
In the first sero survey conducted in Chennai, antibodies were found in one-fifth of the population.
Prakash was hopeful that in the next two months the number of cases on an everyday basis will be brought down to 400, according to India Today. On Wednesday, the city reported 845 new coronavirus cases, taking the total count to 1,92,527.
According to the US’ Centers for Disease Control and Prevention, serology tests are “those that look for antibodies in blood”. “If antibodies are found, that means there has been a previous infection,” it says. “However, there is a chance a positive result means that you have antibodies from an infection with a virus from the same family of viruses (called coronaviruses), such as the one that causes the common cold.”
Meanwhile, the Directorate of Public Health and Preventive Medicine has launched a state-wide sero survey with a sample size of 26,640, The Hindu reported. This survey will be completed by the second week of November and the average number of affected persons in each district will be enumerated.