Jayaprakash Muliyil is the chief contrarian in India’s epidemic story—who famously prophesies two million deaths post-lockdown. Leading epidemiologist, former principal of Vellore Christian Medical College, chairman of the scientific advisory committee of the National Institute of Epidemiology…he explains his theoretical preference for ‘herd immunity’ to Preetha Nair.
We are in Unlock 1.0 and already seeing almost 10,000 daily cases….
Those are people who are positive. It possibly doesn’t mean they are sick. Everybody gets viral infection, all of them are not sick. Over 80 per cent are sub-clinical cases. We call them ‘case’. We keep counting them, we have to count up to 60 crore, that’s when it will stop. I think fear is what troubling us. Fear causes stigma, stigma makes you unjust and unfair. But all this is the natural trajectory of an epidemic. We are mostly rural, so it will slow there, then it will come down. Next year, this time, everybody would have forgotten Covid. We live with lots of viruses anyway. Do we remember any of them any time?
But Covid is different…
It may seem so at the moment. When HIV and HINI happened, people were frightened. HIV was there for several years, torturing us. Now nobody is worried. Only thing is, Covid is a prolonged one.
How do you come to the calculation that India will see two million deaths with a substantial opening up?
Based on the mortality experiences from UK and France, their latest publications. I applied the age-specific corona death rate through our population. India’s population is 1.36 billion: one should see the two million in that context. It comes to about two per thousand, much less than Europe. In India, even small percentages give us large numbers. One per cent of Indians is 13.6 million people. So the number of deaths would be high but the rate of death will be low. Some 1.358 billion will still be alive.
And 7.5 lakh deaths in the age group of above 60?
That’s the most dramatic thing. The death rate is very disproportionate when you take age. Above 80 is over nine per cent of our population. They will have over 80 per cent share of the deaths. We have 36 crore below age 15. My calculations say they will have very few deaths. For a 25-year-old, the risk of dying is still only 30 out of 1,00,000, a very small rate. The equation changes as you go up the age graph. For those in the seventh decade (in their 60s), the rate is 2 per cent. In the eighth decade, it’s 4 per cent. Ninth decade, 8 per cent. In those groups, mortality is anyway high: whether corona is killing them or another disease, it’s not clear.
But we have to open up?
You have to worry about the collateral damages of a lockdown too. Now people are going around sealing hospitals…tragic and ridiculous. People with other diseases will be in danger. There’s a number of Covid deaths we expect. We can’t help it. The focus has to be on providing services.
We have reached community transmission, nobody admits it...it’s a dirty word for everyone. At one point, one can test, identify and isolate, like Kerala did. This is a different phase. A majority will get infected, most will be fine. Only the ones who get breathless are sick. Adequate oxygen supply will save lives. There’s no point testing asymptomatic people. Just treat every pneumonia case as a Covid patient, without testing.
How does herd immunity work?
Let the young go out and work. In the bargain, they will get infected...and be immune forever. They will not die: infection is nothing, they just walk away from it. When many people develop immunity, the virus finds it difficult to get from person to person. I’m an optimist. For one death, there will be 400 people recovering and developing immunity. That becomes an immunity-building population. We expect cities to achieve herd immunity at 60 per cent, villages around 40 per cent. Mumbai will come to that phase very rapidly because they have many cases. Delhi too. The virus doesn’t disappear…it goes into a phenomenal value of R1, a quiet endemic phase where it can remain for months or years. We hope that break will be enough for a vaccine to come.
But protecting the elders may be difficult in India…
You can’t just protect them by issuing a government order. You have to tell them how to protect themselves. Physical distance, hand hygiene, ironing newspapers etc. Make sure even in the house, you wear a mask most of the time. The numbers will come down from 7.5 lakh.
Do we see evidence of herd immunity anywhere in the world?
Herd immunity levels will be different in different areas...you need above 50 per cent level to reach herd. In a thickly populated place like Dharavi, you need a higher level, above 60 per cent, maybe even 80 per cent. With Influenza A, H1NI, we measured it at exactly 40 per cent. Then it died down. I saw it in 2009, then the next year. (New births occur, people move, so there’s always a new population, with a certain percentage who are immunologically susceptible.) It happens by itself. I say it with confidence because I have seen it with measles, Ebola, chicken pox, rubella etc.
Are you hopeful of a vaccine?
I’m very confident a vaccine will come, a good one. All studies on the virus show nice immunogenicity…the ability to stimulate our immune system. So chances are the vaccine is also easy to make. Whether it’s vaccine or virus, it’s our body that produces antibodies. And this virus is not that highly mutant.
Will there be a second wave?
That’s for people who are not immune, never for this virus. My reading is, once you are finished with corona, you are out of it.
What about the reports of reinfection from China et al...
Humbug, not a single report. What happened is, they found the virus in the throat of those who had ‘recovered’ even after 21 days. CDC Atlanta did a careful study...they took the lingering virus and tried to culture it. They couldn’t! So NOT infectious. After the ninth day, nobody had any of the infectious virus in their throat. Then what was that PCR test picking up? Fragments of the virus, not the whole thing. So first we thought it was a peculiar disease that doesn’t go away even after immunity. Now we know. This is the truth currently. But with new evidences, it can change. That’s science.
Is corona here to stay?
The virus has found a balance between itself and us. R0 is the starting rate: everybody is susceptible. Herd immunity means R1: one case leads to one case, no epidemic, just a lingering on in the community. That’s what WHO is referring to. Future outbreaks will happen when the susceptible population increases… after a year or two, when a large number of children are born, Covid can again move around. Young people will block it, but it can kill the uninfected elderly. By the time, we will have a vaccine hopefully.
Experts predict a peak in July.
Luckily, I’m not an expert! Usually it takes three months, not over four months. A lockdown is a break, a temporary delay, so we are slightly better off vis-à-vis the peak. But this epidemic will take away a few elderly. In the process, we have to make sure we don’t destroy our country.
Why are some states so badly affected?
We are taking a snapshot in between…. Everywhere the curve is starting. Wait for it to be over.
Did the lockdown serve its purpose?
They could have given one week’s time, instead of taking people for granted. New Zealand informed the public several days in advance about the coming lockdown. We just announced it and people got caught on the road. Basically, by doing this, we supported the virus.
Would all of us get infected sooner or later?
Yes, sooner or later. We don’t know yet, because 80 per cent is asymptomatic. We can get unduly afraid…. Even at 71, I have 95 per cent chances of living.
Giridhara R. Babu
Epidemiologist, Indian Institute of Public Health, PHFI, Bangalore
Is herd immunity the solution?
One of the largest surveys was done in Spain recently and the results show just 5 per cent of the population was infected in terms of immunoglobulins. Therefore, looking at 5 per cent and so many deaths, imagine the number of deaths if 60 per cent get infected. So, I’m not a believer that herd immunity through infection is going to be the solution. Herd immunity has to come from a vaccine.