New Delhi: Bharat Biotech’s Covaxin is a broad spectrum “buffet” vaccine that will work against all Covid-19 mutations as compared to the other “a la carte” vaccines that will need tweaks, a top Indian virologist said.
Speaking to ThePrint in a telephonic interview, Dr V. Ravi, former dean, basic sciences, National Institute of Mental Health and Neurosciences (NIMHANS), said the Covaxin platform will be effective against all the mutations as it “will produce a broad immune response where one or the other antibody produced will eventually catch the virus”.
“The vaccine is a wholly inactivated virus — that is an entire dead virus whereas other vaccines use some part of the virus. The experience shows that the platform of killed or inactivated viruses have higher chances of generating immune response even when the virus mutates,” said Ravi, who is the nodal officer for genetic confirmation of SARS-CoV-2 virus in Karnataka.
According to him, all the “other platforms, which use either subunits (of the virus) or viral vectors but not the whole virus, such as Pfizer, Moderna, Sputnik, AstraZeneca-University of Oxford, won’t work against the mutated virus and may need tweaking”.
In simpler terms, the Covaxin platform is “like a buffet which produces a variety of antibodies in the human body whereas, the subunit vaccines are like a la carte, where the body produces antibody response for only one or two proteins”, he said.
“However, the advantage of subunit vaccines is they are faster to manufacture. Also, the manufacturers will argue that if a new variant emerges, it would be possible to tinker the spike protein of the vaccine in a reasonably quick time,” he added.
An expert in public health virology, Ravi is credited for establishing the department of neurovirology at Bengaluru-based NIMHANS, which is considered a medical institution of national importance. He also represents India on the international scientific advisory board of Russia’s Sputnik vaccine.
India’s vaccination plan ‘smartly designed’
Speaking about India’s Covid-19 immunisation strategy launched on 16 January, which is set to vaccinate 3 crore frontline workers in the first phase, Ravi said this is the “best strategy” and “smartly designed”.
“While I don’t hesitate in criticising the government, here I must agree that India has applied the best of the strategy for curbing the Covid outbreak,” he said. “Even our strategy to vaccinate the priority groups first is smartly designed and very well thought of.”
He added that not allowing vaccines for the private sector in the initial phase of rollout is a wise decision, considering the need for “equitable distribution”.
“We must understand that there needs to be an equitable distribution of the vaccine in a systematic way. As soon as the market gets into private chains, the regulation will be a huge challenge,” he said.
“The government has to focus on preventing the malpractices such as availability of fake products, leakages in the system, black marketing, upping of the MRPs and other supply challenges. It is best that the priority groups are given shots through government procurement only,” he said.
The carefully-designed vaccination strategy will also prepare the country against the second wave, he said. “If India sees the second wave, because of the super-spreader events or even due to the mutated virus outbreaks, our healthcare workforce will be ready to take the challenge. It’s a very smart move,” he said.
“As soon as vaccines hit the private sector, deserving people will not get the vaccines and social, cultural and political issues will start cropping up,” he added.
‘Should expect second wave’
India should expect another wave of Covid cases, said the virologist.
“All it requires is a couple of super spreader events. History tells us that pandemics always have a second wave followed by other smaller waves,” Ravi said. “Hence it is better to assume we are likely to get a second wave rather than assuming the worst is over. Indeed, we have seen a huge second wave in states like Delhi.”
He added that “even if we hope that our country is near achieving herd immunity — which comes when around 60-65 per cent of the population has had the infection — around 35-40 per cent of the population remains vulnerable”.
So, all those who have not seen the infection yet are either going to get the disease or get immunity via vaccination.
“Smaller second wave was seen in Rajasthan, Gujarat and Madhya Pradesh. In fact, several western countries have seen a huge second wave,” said Ravi.
He advised states to conduct serological surveys to understand how far herd immunity is. “As Delhi has conducted sero-survey, showing it is nearing head immunity, now all states must start conducting the same. In Karnataka, we have begun the same process,” he said.
Analysis of data on clinical severity of UK strain important
According to the data by the Union Ministry of Health and Family Welfare, there were 150 cases of Covid infection due to a mutated strain from the United Kingdom on 23 January.
NIMHANS is one of the institutes involved with the central government in sequencing the samples of people coming in from the UK. The earlier reports from the UK on its variant strain showed that the mutated virus is more infectious than the original one but the clinical spectrum and severity remains more or less the same.
However, Ravi said, “Last week, the preliminary data from the UK showed that in the particular age group the variant can cause serious disease.”
He said, “We need to analyse more data to understand the severity of the strain.” But he added that there is “no need to be alarmed as India has initiated action early and has restricted the entry of the variant well”.
Covid here to stay for ‘at least 5-10 years’
According to the virologist, Covid-19 won’t go anywhere at least for the next five to 10 years. “It will be here but not in a higher proportion,” he said.
He cautioned that “the situation will remain dynamic and if given room to spread, then it will occur in a bigger amount”.
“Once we will cover the majority of the population with vaccination, Covid will remain endemic. It may never touch the baseline but will keep hovering somewhere near to it,” he added.