Balram Bhargava, Director General of the Indian Council of Medical Research (ICMR) on Tuesday warned against non-judicious use of therapies that have not been established for treating COVID-19, citing immune pressure on SARS-CoV-2 virus which can lead to mutations.
"These variations (mutations) occur because of immune pressure on the virus," said Bhargava briefing media.
Bhargava said the immune pressure on the virus may be due to the environment or condition of host, or related to the treatment.
"It is important from the scientific community perspective that we do not put too much immune pressure on the virus, we have to maintain the judicious use of therapies, which are going to benefit. If the benefit is not established we should not use those therapies, as they put tremendous immune pressure on the virus, and the virus will tend to mutate more," Bhargava explained.
Several experimental therapies such as antiviral drugs including Remdesivir and Favipiravir, biologic medications like Tocilizumab, Itolizumab, and convalscent plasma therapy, among other drugs have been tried on Covid-19 patients without large randomised clinical trials proving their efficacy.
Frequently Asked Questions
A vaccine works by mimicking a natural infection. A vaccine not only induces immune response to protect people from any future COVID-19 infection, but also helps quickly build herd immunity to put an end to the pandemic. Herd immunity occurs when a sufficient percentage of a population becomes immune to a disease, making the spread of disease from person to person unlikely. The good news is that SARS-CoV-2 virus has been fairly stable, which increases the viability of a vaccine.
There are broadly four types of vaccine — one, a vaccine based on the whole virus (this could be either inactivated, or an attenuated [weakened] virus vaccine); two, a non-replicating viral vector vaccine that uses a benign virus as vector that carries the antigen of SARS-CoV; three, nucleic-acid vaccines that have genetic material like DNA and RNA of antigens like spike protein given to a person, helping human cells decode genetic material and produce the vaccine; and four, protein subunit vaccine wherein the recombinant proteins of SARS-COV-2 along with an adjuvant (booster) is given as a vaccine.
Vaccine development is a long, complex process. Unlike drugs that are given to people with a diseased, vaccines are given to healthy people and also vulnerable sections such as children, pregnant women and the elderly. So rigorous tests are compulsory. History says that the fastest time it took to develop a vaccine is five years, but it usually takes double or sometimes triple that time.
Bhargava said the UK variant transmissibility is about 60 percent or so, and it is a matter of concern, though the government is testing variations on regular basis.
"Much of the frontrunner vaccines are targetting the Spike protein but the data we have indicate that they will continue to be effective (on the UK mutation as well)," Bhargava said.Bhargava also said they will be carefully monitoring any possibility of immunity breakthroughs that may occur due to vaccination.