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Our Live-in Virus: What Does the Real Covid Map Look Like?

Corona has settled over this landmass like a moving cryptic crossword. Can we really read its clues?

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Our Live-in Virus: What Does the Real Covid Map Look Like?
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Let’s take a step back from a Covid-induced humidity, if such a thing is possible. And rewind to the mid-1980s when another scourge, a real ‘unknown unknown’ that had unnerved the West, was beginning to surface in India—HIV, or the human immunodeficiency virus. Veteran physician T. Jacob John has a vivid memory of a panic-stricken October evening in 1986 when Vellore’s Christian Medical College—where he headed the virology department—admitted one of its first HIV patients. An American, the patient was taken in by evening and at night his room was locked from the outside. The door was opened slightly, tremulously, for dinner—it was pushed towards him by a wardboy who scampered back to safety soon after.

The HIV danger, by then, was real, clear and present—in 1986, the first cases of AIDS in India had been discovered among sex-workers in remand homes in Tamil Nadu. How the infections first started was never tracked down, though it was clear it had come in via foreign visitors and then spread. India’s HIV transmission was largely heterosexual—a later discovery—but the air then was thick with irrational fear, stigma, misinformation. “In the morning,” recalls John, “I had the blood sample and it was positive...full-blown AIDS.” He accompanied the duty doctor on his rounds, went and sat on the patient’s bed next to him, put an arm around his shoulder and spoke to him. “That’s the best lesson doctors got that day,” he says. The story of how India finally wrestled AIDS down began that day—‘social vaccine’, as the term goes. “Public education became one of the cardinal rules for its containment,” says John, who designed the sentinel surveillance for HIV/AIDS that continues even today. Think of all those condom campaigns and the Red Ribbon Clubs in schools and colleges. The world is now gasping for clarity and a new chance against a new enemy—a highly contagious respiratory virus—but that social vaccine jab is what will work for COVID-19 too, he says, long before an actual vaccine comes along.

After all, the coronavirus is, we’re told, something we have to live with. India’s headline numbers of March and April bucked the worst predictions, but now, after four months of living with the virus, we are faced with that experience common to trekkers: the moment you scale a high promontory, a bigger peak swims into view...and then ano­ther. Judging by the altitudes of May and early June, the real Everests may belong to July. “Now the inevitable is happening. Our goal is now to reduce mortality. Let the virus play its game, but we should now protect all the vulnerable people,” says John. That’s why he’s stressing on precaution—the elementary symbols of which are the mask and those physical distancing circles chalked out on the ground. The past few days, India has been reporting a razor’s thin edge short of 10,000 cases daily—the country’s Covid curve saw no peaks or troughs as elsewhere, no jagged edges; instead it has been arching upwards smoothly, like a yogic asana, to break into the world top 10. With the US, Brazil and Russia taking the medals, India has been in the playoffs with Spain and the UK for positions 4-6 with a caseload upwards of 2.5 lakh, inching towards 3 lakh. The original European hotspot, Italy, has stanched its haemorrhaging wounds (for a comparative Covid growth rate graph of all four, with India in the clear lead, see Lockdown story).

The good news is that half of those patients have also recovered—so the count of active cases has just crossed 1.3 lakh, less than half of the total 2,67,614 as on June 9. But could this be the actual figure of infected people? Not likely, say most experts. “We will have some idea of that number once we have some serological data available from the first ICMR (Indian Council of Medical Research) survey that is being rolled out,” says Prof Gautam Menon of Ashoka University, who’s working on mathematical modelling initiatives, including one by the Indian Scientists’ Response to Covid (ISRC). Think of serological studies as a dipstick survey—testing localised groups of people for antibodies in the blood to know the average ratio of the population that had a Covid infection. But until that data is available, a probable yardstick to go by would be 20-30 undetected infections for every detected case, Menon reckons. That range, he explains, is based on the number of deaths—just short of 7,500 so far in India, which can be reasonably assumed to be closer to the real picture (barring a few undiagnosed deaths). How is this done? There’s something called the Infection Fatality Ratio (IFR)—the number of people who die out of all those who actually get infected. This is always much smaller than the ratio of deaths among only the confirmed cases. For COVID-19, the IFR was calculated at 0.37 per cent for a small German town. Extrapolated over Germany by the University of Bonn, even that yielded 1.8 million actual infections—a straight 10 times more than its official figure of 1.8 lakh. Elsewhere, Covid IFRs range up to 0.7 per cent. At this point, therefore, we can only guess at the actual footprint a tiny virus is leaving over this vast landmass.

Zoom in on that map. So far, here’s what we know: about 30 districts account for 70 per cent of the total Covid cases in India—the western states of Maharashtra, Gujarat and Rajasthan coupled with Tamil Nadu and Delhi figure prominently there. But, officials warn that the eastern states—Bihar, West Bengal and Assam, to which the flood of migrant workers flowed—could potentially emerge as the next hotspots. The numbers are beginning to rear their hoods there. Add to this inclement weather—two cyclones in a span of one month and a monsoon season just setting in, bringing with it those familiar seasonal illnesses. The situation’s fluid, literally.

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Take Kerala, which had famously kept its infection count leashed down, but is now battling Round 2 with inter-state movement opening up (see Jeevan’s Sitrep story). Or take Delhi, where daily cases were around 400 in mid-May—now it clocks 1,400. “The cities with more infections may be peaking sooner. The other places, Tier 2 and Tier 3, will progress slowly,” says Dr S.K. Sarin, who heads the Delhi government’s Covid response panel. He foresees a plateau by end-July or mid-August for the capital. “We are in a relatively early stage, and the peak is still several weeks ahead of us. That could be one guess,” says Gautam Menon. “You would really know you have crossed the peak when the number of daily cases begins to decrease.”

Case counts alone don’t offer much granular insight—the states differ on many counts. For example, contact tracing. A recent ICMR study showed wide variations in ‘contacts tested per case’ during the early phase across states—broadly, those with good public health systems did meticulous contact tracing, explains epidemiologist Giridhara R. Babu, a co-author of that study. That’s still easy to grasp, as a function of administrative efficiency. But in many other ways, the epidemic settled over the land like a giant cryptic crossword. What explains the fact that, for instance, while both Tamil Nadu and Delhi carried out a high number of Covid tests over a span, Delhi saw 7.8 per cent testing positive, while it was only 2 per cent in TN?

The ‘test positivity ratio’, as it is called, could point to two things. The simpler explanation: Delhi could have genuinely had a wider prevalence during that period. “Different states are indeed in different stages,” says Babu. “Or again, testing itself could have been made more targeted and efficient, say by zeroing in on as many severe respiratory cases as possible—a syndromic approach.” Sharp, constant surveillance is key. Not the easiest thing to manage during ‘Unlockdown’. Railway stations are opening up, public places coming alive—eventually, places of worship will draw out the devout from their confines, trying to dispel the gloom. What can be done?

Mask-wearing, says John, needs to be enforced like a sacred commandment. “Viral behaviour is as predictable as water going down a slope. So if you have a virus that spreads by droplets, it will infect people by social contact,” he says. “Ultimately, people have to take precautions for themselves and their families. Nobody has understood that. Even now people shift from the ludicrous to the sublime.”

Across the world, lockdowns are tapering off. But the coronavirus still places us in a peculiar spot: there’s a wealth of information about the virus itself, but some fundamental questions haven’t been settled yet. For instance, are asymptomatic patients infectious? Is reinfection possible? We haven’t heard the last word on these yet. That’s another facet of the corona chronicle—a very conspicuous absence of scientific consensus on many fronts. Scientists are indeed working at an unprecedented pace, crossing milestones in days and months instead of years. But the deluge of research reports globally seethes like a stormy, troubled sea. Last week’s retraction of a controversial study on Hydroxychloroquine in leading journals The Lancet and The New England Journal of Medicine came by as a shocker amidst this turbulence. There was a controversial India connection there too (see Data story).

Since the pandemic broke out, scores of pre-print papers—not yet vetted by peers—are being put out every week and some of these hypotheses are hotly debated. “A significant fraction of that would never make it to peer-reviewed publications,” says virologist Shahid Jameel, who heads the DBT/Wellcome Trust India Alliance. “Nevertheless, it’s important for the rapid evolution of knowledge. So whatever one reads in that space must be read with that understanding.” Jay Bhattacharya of Stanford University agrees: “We will need good ideas from everywhere to solve this epidemic.” Some frictions are inevitable, he says. “People working in different disciplines learn for the first time the different ways in which other scientists approach similar problems. This is typical of the scientific process and will undoubtedly be sorted out over time.”

The coronavirus isn’t likely to go away anytime soon. But why did it come? “This pandemic was not a black swan event,” says Sridhar Venkatapuram, associate professor of global health and philosophy at King’s College London. “Any good epidemiologist will tell you that pandemics were expected. And more will come in the future.” But it has created an important need to rethink how societies are connected, he says. Countries may have been flinching back from hyperglobalisation of late, going back into their protectionist shells…but here has come along a microbe, like a voice of the planet, to remind humanity that we are indeed one.

Vox PoP

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Vikram Patel

Pershing Square Professor of Global Health and Wellcome Trust Principal Research Fellow, Department of Global Health and Social Medicine, Harvard Medical School

Will this pandemic radically alter our approach to public health?

It’s hard to predict the long-term consequences of our approach to public health due to COVID-19; remember we had a similar major scare in the 1990s in relation to HIV/AIDS and while the public health response to that particular disease was outstanding, most of the rest of the healthcare system has remained under-funded, under-performing, poorly governed and largely unaccountable. On this occasion, the threat is right at the doorstep of the rich and I hope there will be much greater impact in mobilising support across society for a much stronger public healthcare system.

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Gautam Menon

Professor Physics and Biology, Ashoka University

What does data tell us about the pandemic—its past and future trajectory?

It tells us that the lockdowns have worked in reducing the exponential growth of the epidemic. The doubling times have increased from around 3-5 days at the onset of the lockdown to somewhere between 15 and 20 days at present. However, the effective reproductive ratio remains above 1, indicating that the epidemic is still in its growth phase and the number of new cases each day shows no sustained decline. Thus, relaxing our guard now will inevitably lead to a faster spread of the disease. Our models suggest that allowing people to return to work in a periodic but staggered manner—say with three days on and six days off, with a third of the population at work each time while being effectively locked down otherwise—can reduce the rate at which disease spreads. Our models also point to the crucial importance of rapid, ramped up testing and quarantining of positive cases as the only way to halt the progress of the epidemic.