Health Minister Harsh Vardhan Flags Concerns Over Covid-19 Vaccine

'The biggest uncertainty is that the vaccine may not work,' the health minister said. Another is that the 'efficacy of the vaccine may wane in 6-12 months.'

Outlook Web Bureau

Updated on: 7 November 2020 11:54 am

Union Health Minister Dr Harsh Vardhan believes that with its vast experience in running the largest immunization programme of the world, India is well prepared to deliver the Covid-19 vaccine as and when it is released.

In an exclusive interview to Outlook, Dr Vardhan, however, flagged several ‘uncertainties’ over the vaccines that are now in various states of development.

“You see, there are several uncertainties. The biggest is that the vaccine may not work. The next biggest challenge could be that the vaccine availability could be slower than what we have calculated. Vaccines may have to be imported, which will then throw up the need for reprioritization. Then there is a scientific fact that the vaccine efficacy may wane after 6-12 months,” he said.

“However, I am an eternal optimist. I feel that there are so many candidate vaccines in the pipeline. The whole world is collaborating like never before. We are sharing solutions. Once a part of the population is vaccinated, cases will decline even further making it far easier for us to significantly contain the virus. And of course, there could be a good chance that we may not even need to vaccinate the entire population!” he added.

He also said that so far, no mutation of coronavirus has been detected in India, which would have made it either more transmission efficient or more pathogenic.

“Let me give you the ancestry of the circulating SARS CoV-2 in India. As many as 2,276 virus samples from VRDL across the country were taken. Sequences from other institutions retrieved from GISAID network were also used. The whole genome sequencing was done. We found the variation in clades less than 1 per cent which is not really significant for virulence,” Dr Vardhan said.

Noting that “vaccines are heterogeneous in nature,” he said “therefore, vaccines from different manufacturers may differ in respect to technology/platform used in their manufacturing. If the platform used is a new one, it is treated accordingly to ascertain the safety and efficacy of the vaccine. In India, for example, permission was granted to conduct phase I/II clinical trials of vaccines for Covid-19 to M/s Bharat Biotech and M/s Cadila Healthcare Limited wherein the technology/ platforms used by the firms are different. However, the primary endpoints and secondary endpoints, sample size, population etc. of the two studies are comparable.”

According to him, “The primary endpoint in both the Phase I clinical trials are safety assessment while that in phase II clinical trials are immunogenicity assessment. The secondary endpoint in both the Phase I clinical trials are immunogenicity while that in phase II clinical trials are safety assessment.”