Stejně jako jsme před nedávnem přinesli covidovou pohlednici z Izraele, tentokrát jsem požádal svého bývalého kolegu z UMTM a kamaráda Lakshmana Varanasiho, aby se s námi podělil o své dojmy ze záhadného chování viru v Indii. Koronavirus v Indii je totiž katastrofa, která se nekonala.
Lakshman je profesí biochemik, doktorát studovat v USA, potom pár let pracoval na UMTM a teď zakotvil na univerzitě v Heydarabadu. Občas jsem mu pomáhal proplout útesy české byrokracie a učil se od něj směsi indického klidu a umírněnosti a anglického nadhledu a humoru. Společně jsme pochopili, že český a indický lid je spřízněn neschopností svých vlád a všudypřítomnou dysfunkční byrokracií, na což reaguje velmi podobně – humorem.
S díky a srdečnými pozdravy do země, kde nic čínského nemůže nikdy fungovat
With its legions of diabetics, and people affected by cardio-vascular diseases, India was fertile ground for a COVID outbreak of staggering dimensions. The odds of survival itself appeared bleak, let alone those of successfully containing the pandemic. The country, that by all estimates, should have been the worst hit in the world appears to have trumped the starkest predictions. And it is continuing to do so. The steady decline in COVID incidence in India since September 2020 has been confounding, and it is worthwhile to try to understand how this is happening, such that the findings and insights may be of use elsewhere, or at a different time. What is it about the Indian population that could potentially be the basis for this resilience?
Is the recovery because of the sudden and almost debilitating three-month lockdown in 2020? Only partly so, if at all. There has been an adequate window of opportunity for the virus to spread since the administration began easing the lockdown in June last year. The concept of personal space is not as developed in India as it is in Europe and North America, and the concept of social distancing even less so. To be fair, the size and density of the population, and the heterogeneity in backgrounds makes this harder to practice too. The public’s behaviour at a roadside tea-shop, or at a supermarket in a middle-class residential area is representative of the country’s population, and we can extrapolate from this. Anecdotal evidence suggests that mask-wearing has been generally well observed in India throughout the pandemic. In comparison, European nations (barring Sweden), with smaller and more literate populations, observing social distancing more diligently, have suffered more, out of all proportion to their sizes (that is to say, weighted by population density and size, Europe has been hit harder than India). Does this mean the vulnerability to the virus is a racial or genetic property? The South Asians in the UK have been among the hardest hit demographics there1,2, arguing against a genetic predisposition; but we don’t know, and a genetic component may still be at work. Are Indians in India immunologically superior to Caucasians, where COVID is concerned? If they are, the superiority may be ascribed entirely to immune systems that are challenged more, and more often. Immunity as a cause of the pathogen’s diminished effect in India is probably the only scientific explanation that, at the moment, makes sense. However, there is no objective way of comparing the immune systems of two individuals, or of two races, and neither is there a reference for comparison; there are no physiological markers. Unhygienic conditions breed resistance better than cleanliness does, and ironically, economic backwardness may have been the saving grace (what doesn’t kill one, makes one stronger immunologically). The above is not to mean that people are generally careless about COVID in India. The precautions taken by individuals, and individual families and communities have contributed to containing the spread and must receive credit.
Or is it the climate? This too is questionable. The virus has thrived in hot humid places such as Mumbai, Chennai (Madras), and Cape Town, just as much as in New York City or Los Angeles. Within India too, inland/interior Maharashtra is just as badly hit as its coastal stretch, and Delhi with its winter cold has not outdone Bombay in fatalities.
Or is it that the cases are there but we aren’t seeing them? Various instances indicate that COVID incidence could certainly be reported better; the problem is compounded by the asymptomatic and minimally symptomatic cases that comprise the large majority in India3–5. These may not even be recognized as COVID cases, let alone reported. Likewise the deaths. One problem with assessing COVID using metrics like Recovery Rate (RR), Case Fatality Rate (CFR), Crude Mortality Rate (CMR), or the Infection Fatality Rate (IFR) is that, in an ongoing pandemic, the number of confirmed cases, disease-related deaths, or recoveries cannot be accurately followed, and the said metrics accurately calculated; the metrics are also misleading if not understood or viewed in proper perspective.
A plea to the media would be in place here. Reports of incidence or mortality alone do not help to guide public health action. What is the sense in presenting COVID as a condition that is inevitable? If public response to the pandemic’s dynamics is to be agile, the reagent-data must be forthcoming. People can figure. What tests were used for a population? Antigen, antibody, or QPCR? What is the false positive rate of the test, its sensitivity, and specificity? Which variant did the testing detect? Was the subject asymptomatic, partly symptomatic, or fully symptomatic upon presentation? What proportion of individuals in a population are asymptomatic or partially symptomatic upon presentation? Is the spike in cases because of testing that has been scaled up, or improved? Is a spike local or countrywide?
Reportage of COVID mortality appears to be better than that of incidence; COVID-related mortality roughly parallels mortality from lip/oral cancer in 2020 (approximately 135,000 cases per year), and is lesser than that of Breast cancer.
Are we speaking too soon? Is this the lull in the recrudescence? It is a moot question. If the virus has not hit as hard as predicted in the last quarter of the previous year, when few persons were likely to have resistance to it, could it hit harder now, when a greater number is likely to have been exposed to it? Again, unlikely. Of course, some viral variants of today may be significantly different from the ones of September of the previous year. The virus has had sufficient residence time in a sufficiently large group of individuals to evolve more quickly than it normally would. This is borne out by the greater than 7000 variants estimated to be circulating in India (and possibly the spike in cases in recent days), and by the two strains with altered spike sequences and enhanced infectivity that have already been reported from South Africa since the start of the pandemic. The virus is certainly refining its infective and pathogenic properties as we write these words, but the human resistance (pun intended) it has encountered in India in the first round is reason for hope.
Because the available information is patchy, inferences made here are necessarily based on incomplete data. As we mentioned at the outset, the importance of determining the cause of the resistance to the virus cannot be understated. The extent of seropositivity in the Indian populace would be something to check. Longitudinal studies, on the lines of the US NIH’s Long COVID program, on the persistence of this pathogen and its avatars in the human host will help us understand its long-term effects on human health. The emerging national framework for digital health which, along with the remote healthcare sector, got a fillip last year, will help in this respect. It is a practical exercise and, in the immediate term, will also inform and guide the vaccination drive.
1. Mitigating ethnic disparities in covid-19 and beyond | The BMJ. https://www.bmj.com/content/372/bmj.m4921.
2. Disparities in the risk and outcomes of COVID-19. 92.
3. Most COVID-19 Patients in Delhi Reporting No or Mild Symptoms: Kejriwal. The Wire https://thewire.in/government/covid-19-patients-delhi-no-or-mild-symptoms-arvind-kejriwal.
4. Kumar, N. et al. Descriptive epidemiology of SARS-CoV-2 infection in Karnataka state, South India: Transmission dynamics of symptomatic vs. asymptomatic infections. EClinicalMedicine 32, (2021).
5. Majority of Indian Covid patients asymptomatic as infections top 3 million. RFI https://www.rfi.fr/en/international/20200825-majority-of-indian-covid-patients-asymptomatic-as-infections-top-3-million (2020).
6. COVID-19 Tracker | India. https://www.covid19india.org.