A new sero-survey conducted by the Ahmedabad Municipal Corporation showed that 23.24 per cent of samples had antibodies against coronavirus, indicating that the city has not developed a herd immunity, an official saidon Wednesday. Another survey, conducted to find the prevalence of antibodies among those who have recovered from COVID-19, revealed that 40 per cent of such people did not have the antibodies, he said.
Bhavin Solanki, Medical Officer, AMC, said 23.24 per cent of 10,000 samples showed presence of antibodies, which was an increase of 5.6 percentage points over the sero-survey in July, which had found positivity of 17.68 per cent. A sero-survey involves testing of blood serum to check the prevalence of antibodies against infection.
The latest findings indicate that the city is far from developing a herd immunity which requires 70-80 per cent of population developing anti-bodies, Solanki said. "The 5.6 per cent increase in positivity shows that multidimensional steps taken by the AMC have yielded results in controlling the spread of the virus," he said.
"23.24 per cent positivity shows that we are far from developing any herd immunity, for which the positivity should be 70-80 per cent," he said.