The need to change the composition of Covaxin has not been felt yet in view of good efficacy of the vaccine against mutant variants, the government told Lok Sabha Friday.
There are four mutations of the Covid-19 virus in India at present — two UK variants and one South African and Brazilian variant each, Minister of State for Health Ashwini Choubey said.
Providing details of the efficacy rate of Covaxin and Covishield vaccines against each of the mutations, he said there was no significant difference noted in the efficacy of Bharat Biotech's Covaxin against the UK and the Brazil strains.
However, analysis of Covaxin's efficacy against South African strain is ongoing, he said.
As for the Oxford-AstraZeneca COVID-19 vaccine Covishield, it has shown 74.6 per cent efficacy against the UK strain and has been shown to be effective against the Brazil strain.
However, its efficacy against the South Africa strain is just 10 per cent, the minister stated.
Continuous monitoring of evolution of mutations is being done by the Indian SARS- CoV-2 Genomics Surveillance Consortium (INSACOG), he said.
Besides, National Institute of Virology (NIV) is continuously engaged in virus isolation of different SARS-CoV-2 strains for further research.
Amid surge in Covid-19 cases, the health ministry on Thursday said that 400 patients have been found to be affected with UK, South Africa and Brazil mutant variants of the coronavirus.
On March 4, the country had recorded 242 cases with these variants. The cases increased by 158 in merely two weeks.
"The total number of cases with UK, South Africa and Brazil variants of the Covid virus in the country as on date is 400," the Ministry said in a statement.
A genomic consortium of ten regional laboratories with National Centre for Disease Control (NCDC) as the apex laboratory has been established to perform genomic sequencing of the samples from positive travellers and 5 per cent of the positive test samples from the community.
Strains from South Africa and Brazil have been detected in travellers coming to India from these countries. In order to curtail spread of these variants in India the government issued revised guidelines for international arrivals on February 17.
As per the guidelines, screening of passengers coming from South Africa, Brazil and the UAE has been made very stringent to prevent spread of infection due to variants, Choubey said.
On whether the government proposes to bring about changes in the existing vaccines available in the country to check the further spread of these two mutant strains, he said Oxford-AstraZeneca have initiated tweaking of the vaccine to make it efficacious against the mutant strains particularly the South African variant.
"The need to change composition of Covaxin has not been felt yet in view of good efficacy of the vaccine against variants," he said in the written reply.