Coronapod: The variant blamed for India’s catastrophic second wave

Benjamin Thompson

Welcome to Coronapod.

Noah Baker

In this show, we’re going to bring you Nature’s take on the latest COVID-19 developments.

Benjamin Thompson

And we’ll be speaking to experts around the world about research during the pandemic.

Amy Maxmen

We’re entering a new era now. We have new COVID strategies, there’s some new unknowns and we’ve got a vaccine.

Benjamin Thompson

Welcome to the latest episode of Coronapod. I’m Benjamin Thompson in the hosting chair this week, and I’m joined on the line from Sydney, Australia by Nature’s John Pickrell. John, thank you so much for joining me today.

John Pickrell

You’re welcome.

Benjamin Thompson

John, you’re a new voice on Coronapod. Could you tell the listeners what you do here at Nature?

John Pickrell

Yeah, I run the Asia-Pacific Bureau. We cover and coordinate all of Nature’s news coverage from the Asia-Pacific region, covering India, China, Australia and the Pacific.

Benjamin Thompson

Well, let’s stick with India today for this episode of Coronapod, John, and of course, listeners around the world, if they’ve opened a newspaper up or gone on to a news website, they will have seen the situation there. I mean, let’s be honest, they’re in the middle of a devastating second wave of COVID-19. What’s the overall situation at the moment?

John Pickrell

Yeah, I mean, it’s absolutely catastrophic in India. For weeks now they’ve been having daily case numbers, kind of 400,000 new cases a day or somewhere whereabouts that number, so they’ve really been having higher case numbers there than any other country has had, and they’ve been breaking records for the highest case numbers of any country for weeks now.

Benjamin Thompson

I mean, you’re absolutely right – shocking statistics – and understandably, scientists are racing to try and understand what’s driving this second wave, and we’ve got an article about that in Nature this week. And it’s really looking at sort of different variants of the virus, and one in particular that’s of great concern.

John Pickrell

You’re right. Scientists have been racing for some weeks now to really work out what was going on in India, and it was kind of puzzling because, before the latest surge many people had been infected, and also more than 100 million people had been vaccinated in India, and that’s coming up to 10% of the population being vaccinated even before this surge began. So, it was very puzzling to scientists initially that this massive surge was able to take root because they thought that many people, certainly in India’s mega cities, had already been infected and had some natural immunity already. A couple of weeks ago it appeared really that there were different variants driving surges in different places, but India has relatively limited sequencing capabilities. But as they’ve ramped up their genome sequencing capabilities they’ve seen that one variant called B.1.617 has really spread to many different places where other variants seem to be the predominant variant previously. And what that’s really suggesting is that B.1.617 is more transmissible potentially than some of these other variants, and that’s why really it’s managing to rapidly spread all over India, and really it’s been of great concern, and that’s part of the reason that the World Health Organization designated that variant as a variant of concern earlier this week.

Benjamin Thompson

When we talk about variants, John, I think just a quick recap I guess, this means that there has been in a change in the genetic code of the SARS-CoV-2 virus that maybe confers the virus with the ability to potentially spread more efficiently or what have you. And clearly researchers have been sequencing this B.1.617 variant – what have they found?

John Pickrell

Yeah, so I mean, the virus is constantly evolving and new variants are appearing in different places. Some of these variants pose kind of a new threat, and other mutations and changes in the viral genome are relatively benign. But one area that scientists are particularly interested in is the virus’ spike protein, which allows it to gain entry into certain cells. So, one of the groups in India who’s been studying the virus, they looked at the spike protein and they found eight mutations in that spike protein, and a number of these have been kind of concerning because two of them look similar to mutations that have allowed other variants of concern to become more transmissible, and a third resembles a mutation that was found in another variant called P1, which caused an outbreak in Brazil earlier this year. And they found that that third mutation resembles one that may have allowed the P1 variant to partially evade immunity and led to that outbreak among people who’d already been infected with the virus in Brazil.

Benjamin Thompson

So, if that’s what’s going on with the genome, is there any idea of how these changes are affecting the virus’ abilities?

John Pickrell

So, the genomic work is really important to show us some of these different mutations, but then to kind of actually see whether these mutations are allowing the virus to be able to enter cells more efficiently or have other effects, we have to actually test it. Some experiments in hamsters seem to show it causes some more damage and inflammation in the lungs, but really all of these tests are very, very preliminary at the moment.

Benjamin Thompson

Well, early days in this research, as you say, but of course hamsters and humans are very different beasts.

John Pickrell

You’re absolutely right. I mean, that’s what some of the scientists said. They said these studies in hamsters are kind of indicative but really there needs to be studies, particularly around the stuff to do with the severity of the disease with this variant, in people.

Benjamin Thompson

Well, obviously we live in a different world than we did six months ago. Is there any work on how this variant may be affecting the efficacy of vaccines or of immunity kind of in general?

John Pickrell

Yeah, there have been several studies looking at antibodies, so they took blood serum from people who’d received their Pfizer vaccine, and they tested the blood serum against some kind of modified versions of the mutations from B.1.617, and what they found was that the kind of abilities of some of the antibodies in that serum to block or neutralise the virus and prevent cells from getting infected was slightly limited. So, they found that some of the neutralising ability of those antibodies was reduced. So, it certainly appeared that this variant may be able to evade some of the immunities of vaccines, but then other scientists have pointed out that vaccines tend to induce the body, the immune system, to produce vast quantities of these neutralising antibodies. So, even if this variant is able to evade some of that immunity, may not be impacted quite so much by those neutralising antibodies, it may not be enough to render the vaccines ineffective. So, it certainly appears at the moment that the vaccines would still be effective against this variant.

Benjamin Thompson

And there’s two vaccines currently being used in India as I understand. Do we have any info on how they might be affected?

John Pickrell

So, there have been very preliminary studies which actually tested the two vaccines that are currently being used in India. So, one of those is the Covaxin vaccine made by Indian firm Bharat Biotech, and the other one is the locally produced version of the Oxford-AstraZeneca vaccine which is called Covishield. And certainly, at the moment, it appears that those vaccines are still effective against the variant, but they’re very small studies with small sample sizes, so really they’re just at the beginning of trying to work out what’s going on with this variant.

Benjamin Thompson

Yeah, which I think echoes what we’ve seen with previous variants of concern, that it isn’t an on-off situation. It may lessen efficacy in some way but yet you’re still conferring some protection.

John Pickrell

Yeah, so it certainly appears people need to continue to get vaccinated and hopefully as India ramps up its vaccine effort, then it’s going to help bring these outbreaks under control, but we just have to see what happens.

Benjamin Thompson

Yeah, is that the key to it? I think we’ve talked on previous Coronapods that if you can stop the spread of the virus, you reduce the chance of new variants arising.

John Pickrell

Yeah, so as I pointed out earlier, more than 100 million people out of 1.4 billion had received the vaccine really before these outbreaks began, and I’m not on top of where they’re up to with their vaccination programme, but they’re probably up to the 200 million mark by now. But, I mean, you really need large swathes of the population to be vaccinated to have a big impact on the spread of the virus, so I think India is probably unfortunately still a long way from that point.

Benjamin Thompson

Well, clearly there are a lot of questions that need to be answered about this variant, and this is definitely a story we’ll be keeping a careful eye on. But for the time being, let’s leave it there. John Pickrell, thank you so much for joining me today.

John Pickrell

No worries, thanks.