In this interview, renowned epidemiologist Eric Feigl-Ding, a Senior Fellow at the Federation of American Scientists in Washington DC, shared his thoughts about the Delta variant of COVID-19. “In certain ways, the Delta variant has burnt through the forest, it has infected much of India…” he said. On the risk of multiple waves within short spans in India and the current pace of vaccination, Feigl-Ding said that it is hard to predict if there will be an exact repeat of the previous wave.
Read the full interview:
You have suggested that the DeltaVariant will outpace all other variants and become dominant in US by end of July, if not earlier. How vulnerable would the US still be?
Parts of the world that will be vulnerable are ones that have lower than normal vaccination rates. In parts of the US that are heavily vaccinated, the surge will not be able to penetrate. But there are parts that have really low vaccination rates, those will see a surge. Just like UK is seeing a surge in North West England and Scotland. And we know that one dose of the vaccine is not enough. With Astra Zeneca two doses, you get only 60 percent protection, with one dose only around 30 percent or less protection. And that’s for symptomatic. There are millions and millions of people who are not vaccinated and symptomatic efficacy of 30-60 percent is just not enough to contain the virus. If you are vaccinated, you can avoid severe disease, death or hospitalisation for the most part. But with 30-60 percent efficacy, and with most of India and the world with only one dose vaccinated, if you are even vaccinated, it means that we all continue to be vulnerable.
India’s National Institute of Virology has detected a new variant B.188.8.131.52 via genome sequencing of travellers from UK and Brazil to India. Your thoughts on the Delta variant (from India) and its mutants?
Delta variant is the most worrying. For other variants, we don’t have enough data on. Delta variant is one of the most infectious and one of the most severe. This is about 50-70 times more infectious than the previous alpha variant from UK. That one is itself 50 percent more infectious than the Wuhan original strain. That put together, the Delta variant is about two times more contagious. But the severity is around 2 ½ times more severe when it comes to greater risk of hospitalisation compared to the UK variant. And the UK variant is around 60% more severe than the original. So, if you multiply that puts Delta variant at four times greater risk of hospitalisation than the original Wuhan strain – that is quite a number – twice as contagious and four times more severe. This is obviously why we have seen such a horrible pandemic situation in India in the last month or two. It is also a lesson from the world, that even though UK has been heavily vaccinated and is one of the leading countries of the world for vaccination, yet it is still seeing a surge specially in north west England. It is seeing an exponential rise in hospitalisations. This means world is not safe till we have vaccinated the world.
Delta variant is one of the most infectious and one of the most severe.
How much at risk of multiple waves within short spans is India currently at given the Delta variant and the current pace of vaccination?
It is hard to say whether we will get to see a repeat of the exact same wave. In certain ways, the Delta variant has burnt through the forest, it has infected much of India. That is why we have seen such high death tolls. Some people estimate some 1.5 million people have died. Lower ends are around half a million, upper ends are around 3-4 millions. Best guess is that at least 1.5 million people have died. The virus having burnt through so much of India means that maybe the future waves may not be as bad. But one thing we have learnt is that the virus will mutate and learn to adapt. Reinfections are certainly possible. Virus that is most successful in learning to be contagious or more re-infectious is the variant that will come back and bite us. We have seen that with Brazil, with the Delta variant as well. Lesson is that Covid pandemic is not over unless we combine both vaccines and mitigation. More bodies of infections means more mutations.
In certain ways, the Delta variant has burnt through the forest, it has infected much of India. That is why we have seen such high death tolls.
Dr Fauci told India Ahead that one dose is not enough protection for the DeltaVariant B161712. Was it sensible to increase the gaps between the two doses then of Covishield in India then?
Previously, it was a sensible decision because for the original Wuhan strain and for most part of the alpha variant, one dose did provide decent partial coverage. Then, you could argue that more people with partial coverage gives more protection than fewer people with full coverage. The math has changed. With the Delta variant one dose is incredibly incredibly low efficacy. With that extending more people with just one dose is not enough against the Delta variant. It was previously enough when one dose would give you 60-70 percent protection and two doses would give 80-90 percent protection. But one dose for Delta variant is clearly just not enough and we need to prioritise two doses for everyone.
The decision in India was also driven by the demand and supply gap because of acute vaccine supply shortages. Your advice would be that we need to revise the dose gaps for Covishield vaccine?
Yes, absolutely. We really need to switch to two doses now. One dose is just not enough. The neutralisation is so much lower. We know that neutralisation in people decreases with age. With the Delta variant, you start among younger people with such lower base line of neutralisation that it is lower than neutralisation against the older virus among older people. Basically the starting neutralisation among the 20 something olds against the Delta is lower than neutralisation for 60-70 year olds against the Wuhan strain. That just says that basically the Delta variant is so tricky and such a greater dilemma to stop that we really have to rethink our entire strategy around this pandemic. What used to minimise risks and keep infection rates down will not work against the Delta variant. What use to work in keeping bars and restaurants open, masking half the time, not masking in schools, some areas you could get away with. But not anymore because of how contagious it is. We are seeing this in UK where infections are soaring because in schools they don’t use masks. Kids are incredibly vulnerable. Overall, one percent kids who are infected are hospitalised. If you ask any parent is one percent hospitalisation rate for your infected child an acceptable level of risk? Most parents would say no. Kids are vectors and they spread it to communities. That’s why we see number one infected group is kids. Number two, 30-40 year olds, parents of school kids. This is why we have to have to vaccinate children soon as well.
What used to minimise risks and keep infection rates down will not work against the Delta variant.
There are apprehensions of a third wave being fatal for children. Is there truth to such fears ?
We need to protect kids for many reasons. Kids transmit to adults and other people in the community. They and schools are a transmission nexus. It is not just deaths. I mentioned one percent hospitalisation. Granted not all of them will lead to deaths, but there are severe diseases that kids can have like inflammatory illness and also long Covid. Kids do get long Covid. Period. Even Dr. Fauci acknowledges this. About 1 in 7 people have long Covid. Presumably similar ratio in kids. We don’t want those risks to be carried by kids for the rest of their lives. There is transmission risk, hospitalisation and mortality risk, and there is long Covid risk. Also want to remind people that it is not just how severe a disease is. If you infect enough people, virus is more dangerous if it actually balloons the total infected and that leads to increased hospitalisations and deaths even if the risks are low. This is why we have to minimise transmissions and we cannot assume that kids are immune or as if they are vaccinated. Long Covid complications are something we should not over look.
In India, vaccines for kids in trail phase and even 12+ adolescents haven’t started receiving jabs. When will it be safe for children to go back to classrooms in India? Given that there are no vaccines yet for children and the slow vaccination rate in India.
We can open/ re-open schools but please mask children. Children over the age of five should be masked as per the CDC. They don’t do it in the UK and UK now has one of the largest surges in kids. Masking is important. Ventilation is also important. Open the windows. This is an airborne virus. This is not as much handwashing as it is the fresh and clean air that is needed. The more expensive air solutions are like hepa filters or UV disinfections. But cheapest solution is open the windows. If it is cold you can wear a jacket, if it is hot you can switch on the fan. But opening windows is one of the most effective things you can do to minimise Covid risks. So, masks and ventilation are the most simple basics. We can open schools safely if we have those in place even before vaccines are fully available.
Masking is important. Ventilation is also important. Open the windows. This is an airborne virus. This is not as much handwashing as it is the fresh and clean air that is needed.
Is that something you would even advise for a country like India given the poor air quality index and air pollution challenges even pre-Covid? Dr. Faheem Yunus seemed to suggest that external environmental factors – air quality, water hygiene need to be factored in for rise in cases of Mucormycosis.
The Black Fungus phenomenon is partly steroids but also partly diabetes. Covid is exacerbating diabetes along with steroid use in Covid. But air pollution is a point. If the air quality is poor, keeping the windows closed probably will not improve that much. To improve the air quality, you really need these Hepa or advanced Filters. Not every private family can afford it, but hopefully schools and state governments can keep one in every classroom, granted its about 200 USD. But when ordered in bulk, in millions, the price can come down. That would remove both viruses and air pollution. I would also argue that even if air pollution is bad, protecting kids during Covid risks, is just as much of an important priority. Opening windows will definitely reduce Covid risks.
If the air quality is poor, keeping the windows closed probably will not improve that much. I would also argue that even if air pollution is bad, protecting kids during Covid risks, is just as much of an important priority.
But Dr. Faheem Yunus argued that if diabetes were to be blamed for black fungus, it has not been the case US, Brazil or Europe, which are hotspots for diabetes and obesity. So we need to look at more external factors?
We should definitely look for more factors. Other experts have said that steroid use have been already high before Covid. So, if it was just steroid use alone it would have been seen. Steroids have been widely used and should not be the main driver of this new Black Fungus epidemic. It is a combination of Covid exacerbating diabetes plus steroids and other factors that we do not know of yet. As the Delta variant is surging in UK and countries, maybe we will have more clues.
As some of the states and bigger cities in India start to unlock again, keeping in mind only some four percent of the population has been vaccinated yet, will lockdown remain an important tool to break down the transmission chain moving forward?
I am not the biggest fan of lockdowns. Lockdowns do work, there is evidence, but they cause a lot of economic pain. We should not prioritise economics over everything. But there are things you can do before you reach the level of lockdown. Lockdown is what you do when you run out of options and the epidemic curve is nearly a steep one. But before it reaches that bad exponential rise phase, hopefully governments will react faster on these other mitigation steps. But if we do lockdowns, we have to support people. There must be state subsidies for working class people in order to comply. If you have a lockdown without compliance and no support like free food, medicines delivery and social services, then the lockdown will be ineffective and drag out the pandemic longer. In certain ways, countries that supported lockdowns with financial assistance, and delivered food to communities like they did in China, are the successful ones, but it requires really good coordination and governance. But not all countries are equipped to do that.
If you have a lockdown without compliance and no support like free food, medicines delivery and social services, then the lockdown will be ineffective and drag out the pandemic longer.
There is a lot of focus on external sanitisation as malls, offices reopen. What does the evidence say on surface transmission and how do you prevent aerosol transmission especially in indoor spaces?
We don’t think surface transmission is a major source. Like touching a door knob or something like that. Major source is airborne transmissions – long distance aerosol transmissions especially. Old thinking was that most droplets are pulled down by gravity. They are but aerosols stay in the air for a long time. Best way to solve it is ventilation. But buildings that cannot open windows or if there is air pollution outside, hepa filters and UV are the two standardised methods. Do not rely on other source of air purification or filtrations. There are a lot of scams and quack products out there. Stick to Hepa Filtration or UV disinfection. Hepa filters is something that has been installed in the central air unit or the affordable air cleaners. This is unfortunately not economically feasible for every home. But in large buildings, shopping malls, offices these should be installed. UV is the other thing that can kill the virus and has to be installed in the central air system or in large venues near the ceiling by creating a zone and near the ceiling where it does not harm the people and circulating the air up and down it almost kills the virus. Those are the only two scientifically proven methods of disinfection but ventilation is of course effective.
We don’t think surface transmission is a major source. Major source is airborne transmissions – long distance aerosol transmissions especially.
How vulnerable are individuals still to aerosol transmissions if they are just jogging in the park which may be moderately crowded?
Outdoors is not that risky. Most of the time, unless you are in an incredibly crowded concerts or religious ceremonies in which people are packed together. Unfortunately, in India and in some other parts of the world, over crowding is a serious problem. But if you are outdoors in the park just by yourself or with your family and there is some distance from other people, outdoors is pretty minimal with risks. If it gets overcrowded you always have greater transmission because the ventilation around is not adequate.
Biden administration is likely to buy 500 million doses of Pfizer #COVID19 vaccines to donate to the world. What should the cooperation be like with country the size of India and current pandemic scale ? What should the distribution plan be like for the unused vaccines?
It is really heartening that Biden will announce this decision at the G7 summit next week. This is on top of the multi billion dollar commitment of US to Covax which has its own distribution system. It will be a couple of months before the Pfizer doses are available but I am hoping it will be targeted towards high priority areas where there are surges as well as places where they are least able to afford vaccines. As supposed to other things like technology transfers, patent waivers, we should still work to waive patents and tech transfer a lot of vaccines so that other smaller manufacturers can also build these vaccines. In a pandemic with huge economic costs, it is very selfish if these companies do not share their knowledge of the vaccines with the world. There is no robust economy unless we get the pandemic under control. I am hoping that we ramp up vaccines as much as possible and share with the world, not hoard it and share with countries that need it the most.
Any thoughts on India’s indigenous Covaxin which is yet to get a WHO approval so far?
I think Covishield-the Oxford-Astra Zeneca vaccine is pretty good. The Novovax vaccine which you call Covovax is also very promising. Hopefully, that will be approved soon. On Covaxin, I am not really sure because we have not seen peer reviewed studies on that which have to be published. But Covaxin is inactivated vaccine somewhat like the Chinese Sinovac and Sinopharm. Some of them have been weaker in efficacy. We have seen around 50 percent efficacy for some of them vaccines. So we are not quite sure. We have to look at the data if they are not only efficacious but also efficacious against the variants. Those are outstanding questions. In certain ways, some of the most effective vaccines that we see today are the mRNA vaccines. For example, Pfizer is 88 % effective against the Delta variant in one study while in the same study AZ-Covishield vaccine is only 60% effective. That 28% gap is a huge difference. In certain ways for protecting against mortality all the vaccines are good. But for preventing transmissions some are better. But if I had a chance I would take any vaccine that is available.
In certain ways for protecting against mortality all the vaccines are good. But for preventing transmissions some are better. But if I had a chance I would take any vaccine that is available.
Mixing and matching or top up of vaccines for those waiting for second dose of Covishield, would it be advisable?
In Europe, they have already approved switching from AZ to Pfizer vaccine. In Spain, they have also done a study that those who got their first dose of AZ, they were able to switch to Pfizer as a second dose. There are also studies that show mixing vaccines could be promising but those are still pending. We need to carefully go through studies to see what should be more widely adopted. But it has also been used by many other countries where they have mixed vaccines but there has not been many such adverse reports about mixing. I am hopeful about mixing vaccines. We have seen it for other diseases too. But the study has to be different for each virus. This is not medical advice.