CHENNAI: Even as the worry over COVID-19 looms large over our heads, the State and the country is nearing the end of phase 2 of the lockdown. Experts believe that antibody testing is one of the ways to move forward and identify the herd immunity ratio, at least until a vaccine is found for the pandemic.
Dr Subramanian Swaminathan, Senior Consultant of Infectious Diseases at Gleneagles Global Health City says, antibody testing could be a temporary fix for this problem, by being part of surveillance.
“When the population reaches herd immunity, it means there are not enough people vulnerable. This testing may help to identify that ratio of the vulnerable herd,’’ says Swaminathan, quickly adding that it is not a foolproof method, and could make minimal sense.
Jacob John, an expert in Virology says, testing for Immunoglobulin G (IgG), an antibody which develops after IgM, can be long-lasting and ideal to identify and release people for economic activities, hinting at the possibility of certifying them ‘immune’.
“The IgG develops for any infection, and we can assume it is the same for COVID-19,’’ he says, before adding that the height, duration and robustness of the virus still remain unknown.
However, there is currently no evidence globally to prove the success of these tests, although it is ongoing.
Dr Swaminathan places concern on the testing’s viability because globally, various mutations of the virus have been observed. “One may test IgG positive, but since COVID-19 has mutated, the patient may still be vulnerable,’’ he says.
The World Health Organisation (WHO) had recently published a briefing titled ‘Immunity Passports’ on its website, which said, “As of April 24, no study has evaluated whether the presence of antibodies to SARS-CoV-2 confers immunity to subsequent infection by this virus in humans.”
Experts opine that antibody testing won’t serve as a proof of immunity, but can be an intermediate process of identifying antibodies at least until vaccination is found.