New Delhi: Herd immunity for coronavirus is a “myth” in India because at least 80 per cent people need to have antibodies for the whole of the population to be protected, Dr Randeep Guleria said.
This, he said, would be difficult if one takes into account the new Indian strains found in Maharashtra — which could be highly transmissible and dangerous. The new variant, he said, can even cause re-infections in people who have developed anti-bodies to the virus.
240 new strains of the virus have surfaced across India, which are behind the fresh surge of infections the state has been witnessing since last week, Dr Shahshank Joshi, member of Maharashtra’s Covid Task Force has said.
Besides Maharashtra, four more states — Kerala, Madhya Pradesh, Chhattisgarh and Punjab — have been witnessing a spike in numbers.
The government’s vaccination plan depends on creating herd immunity by immunising a critical mass of people. In the first phase of vaccination, the government plans to immunise 3 crore health workers and frontline workers. After it will be the turn of 27 crore people who are above the age of 50 years or have co-morbidities.
Explaining why herd immunity is not achievable, Dr Guleria said mutations or variants in the virus have “immune escape mechanism”. They can threaten the immunity achieved by a person through vaccinations or the disease and cause reinfection.
“India needs to go back to aggressive measures of testing, contact tracing and isolating infections,” he added.
Asked if the COVID-19 vaccines in India be effective against the new strain, Dr Guleria said the vaccines will be effective, but their efficacy might be less. For example, people might not be able to avoid getting the disease, but they will have a mild version of it.
Regular surveillance data is the key to knowing if vaccines need to be modified to fight the new variant strains. In the coming months, there could be changes made to the vaccines.