Second Sero Survey in Ahmedabad: No herd immunity yet, 40% of Covid recovered patients lack antibodies

A new sero survey conducted in Ahmedabad has found that 40% of recovered Covid-19 patients have no presence of antibodies against the coronavirus. With 40 percent of the patients, despite having recovered from the virus, remaining vulnerable to re-infection the finding could sound the death knell for experts who were rooting for herd immunity as a possible solution to the deadly pandemic.