The coronavirus disease (Covid-19) first appeared in the Wuhan district of Hubei province of China in early December 2019. The first case was reported by China on January 7, 2020, and this aroused variable interest worldwide, with most countries initially ignoring the novel infection. Fortunately, Indian health authorities sensed the danger, largely because the country has always been alert to new infections. The scientific think-tank at the Indian council of Medical Research (ICMR) became active immediately and the first laboratory confirmed case was identified at ICMR’s National Institute of Virology (NIV), Pune, sometime towards the end of January.
A look at the world Covid meter shows that there is striking variation in mortality rates across countries, ranging from 0.2% to 15% depending on age, the smoking habit and pre-existing co-morbidities. It may be too early to tell, but in general, countries in the Northern hemisphere have faced the maximum brunt, and those in the Southern hemisphere (and those located proximate to the Equator) have so far escaped high infection numbers.
Three factors seem to be playing a role in the observed lower numbers in India with almost zero occurrence of severe Covid-19 cases (until now). First, broad-based immunity in the population due to the extensive microbial load. The Indian population has been exposed to a vast variety of pathogens, including bacteria, parasites and viruses leading to the generation of broad specific memory T-cells in the system, ready to attack additional foreign invaders.
For example, the three main killers of Tuberculosis, HIV and Malaria have plagued India, Africa and several countries in the Southern hemisphere much more than the European and North American nations. In the context of CoV-2 coronavirus, the beneficial role of chloroquine and hydroxychloroquine has been much talked about and debated, while there has already been an extensive usage of this drug at the community level in India — this too may ultimately prove beneficial.
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Second, epigenetic factors that include environment and food habits may also play a beneficial role for countries such as India; much literature is already available in Ayurveda and other Indian systems of medicine on the definitive beneficial effects of Indian spices in augmenting immunity.
Third, and most important, is the possible role of immune response genes in the Indian population. These genes are collectively referred to as comprising the human leucocyte antigen system or simply, the HLA genes. Their main biological function is to present invading foreign antigens to the immune systems, since T-cells, which act as the body’s soldiers come into play only when pathogens are presented to them in a more formal manner in association with HLA genes. In other words, the pathogen must first attach to compounds created by HLA genes before T-Cells attack it. If no such compounds are produced by the body, then the T-Cells are ineffective. As a consequence of the microbial load, the Indian population possesses a high genetic diversity of HLA, much more extensive than Caucasian populations. Indeed, studies by the author at the All India Institute of Medical Sciences, New Delhi, over several decades revealed the presence of several novel HLA genes and their alleles in the Indian population, most of which do not occur in other ethnic groups. Such genetic diversity of HLA could affect viral fitness.
The question then is: Why should genetic variation in HLA genes play a role in the Covid-19 progression? One hint comes from earlier studies in related viral diseases: Certain genetic variants of the HLA system provide protection against such viruses, while others increase genetic susceptibility to them. Another source of indirect evidence comes from recent clinical Covid-19 studies which showed that rapid T-cell response appears to be crucial for recovery from Covid-19, and reduced functional diversity of T cells in peripheral blood could predict progression of Covid-19.
The big question is: Does this give Indians a better chance at fighting the virus effectively? From the epidemiological data so far, it seems so (although much more extensive research is required). However, it is important for us to keep viral loads in check and below the threshold levels. In this context, the complete lockdown announced by the government is highly timely and most desirable. It is imperative that the virus replication cycle gets disrupted as early as possible before it gains numbers that may become difficult for us to counter.
To this end, the images of crowds gathering in several places whether for panic buying or interstate movements are disturbing. They could jeopardise all efforts and mitigate whatever natural advantages we enjoy.
The State must act fast to enforce the lockdown, even forcibly if necessary. India may be the outlier in fighting the coronavirus infection and succeed in keeping the overall numbers lower than the rest of the world with minimal deaths.
Narinder Kumar Mehra is the ICMR National chair and former Dean of the All India Institute of Medical Sciences, New Delhi
The views expressed are personal
By special arrangement with 
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Just few days back all these experts were giving horror story that there will be more than 500 million corona cases in india and more than 2 million will die. Now Modi with strong hand approach and with people’s (Non Tablighi’s) whole hearted support seems to be succeeding in effectively controlling it. The Print and other traitors cannot digest it. They wanted to see 2 million death because of corona and then blame Modi for it. Their dreams are stand shattered. Now they are worried the credit will go to the government and the leadership, so they want to raise a bogey of natural immunity, weather etc.
Bunch of nonsense. why did 1918 flu killed 20 million in India? If the author is so confident then Modi should open India as there is nothing to worry about.
The author is a former dean of AIIMS. He must be knowing what he is writing. I am not a medic. But just because I cannot play the ball, I wont play the man.
Wtf even here. More than coronavirus, people die with ego related diseases.
Complete junk that should not be published. The only reason the number of cases is low in India is because of inadequate testing. India is testing less than 40 people per 1 million. New York is testing 9,000 people per million. No testing = no cases. Wishful thinking.
If that is the reason then we would have been witnessing alarming number of deaths from all over the country and specially from slums where people live in close proximity, but that is not the case. Our genes, habits and weather is helping us against covid 19.
It’s a serious matter, based on Scientific studies, with emperical postulations.
Rhetorical comments are of no consequence.
Making fun of India’s traditional food habits had been a happy pastime for the blind brains.
Will somebody explain No Covid 19 Casualty in Workers gigantic migration of 15 millions, to East UP & BIHAR !
Also very little Covid 19 Cases in NE, EAST & East Coastal India, raises definite issues of some valid Resistance/ Immunity in this part of the Country’s population’s DNA.
I am a few years off 80. Just as a matter of interest and re the Black aDeath or great plauge of centuries ago. Test done on the descendants of survivors reveiled that these descendents were carrying a protective gene inherited from their earliest European ancestors. Hence the reason that their ancestors survived the great plauge.I hope this is of interest. Thank you for reading.
Years later, we may also do a similar study and find that COVID-19 did the same to us.
It killed off those of us without protective genes as we did not practice physical distancing well since we assume Yoga, Turmeric and last year’s diarrhea made us immune.
Indian are not that immune. Even today, Indians die 20 times more than Americans, 32 times the British and 133 times Russians from common diarrhea, even when adjusted for population. To hope we would be specially immune for a disease we were never exposed to is delusional.
https://www.worldlifeexpectancy.com/cause-of-death/diarrhoeal-diseases/by-country/
The writer of this article is a F**king idiot. The only reason India has few cases today as compared to other nations is because of the 21 days lockdown initiated by our Government !! Everything else is a lie !! Social distancing and the hardwork of doctors and Police. Such people should be punished for spreading misinformation in such perilous times . You want to maintain the status quo , then blisten to the government and cooperate . Do it for your elders if not for yourself . Don’t be the reason for someone else’s death. STAY HOME STAY SAFE !! DOWNLOAD Aarogya Setu App by government. It’s a great initiative , just like what they did in South KOREA.
You are a lowly worm, So you are the expert here? What is your medical qualification? i doubt if you even have a basic qualification considering your unciviled post.
That’s right……
This is not a time to make unsubstantiated claims. This crap isn’t supported by scientific evidence.
Some time back, a message floated around in social media claiming that we Indians are exposed to more diseases and infections than western and other countries, and we have the required resistance to overcome COVID 19 also. Rather frivolously, the message added that the spices and chilli we eat will kill Covid 19! Be that as it may, I hope that if the inferences in this article are even reasonably plausible, that explains low infection and mortality rate in a huge and populous country like India.
We are late in getting C19 only because no Chinese visits India. Chinese tourists were swamping Italy Spain UK New York. These are hot spots today. Tomorrow is our turn.
This is conjecture and should not be printed. It will prompt Indians to lower their guard and not be vigilant about prevention. Misinformation
Mortality rate in India is low right now, as testing rate is abysmally low. Also actual mortality rate comes after a lagging time of 10 days. First the patient has to develop symptoms, thereafter wait for the test results. Even though Indians may be genetically predisposed to fight viruses better than Caucasians, due to pollution, undernourishment, bad drinking water and other diseases ( TB), Indian population has to be considered weakened right from the beginning.
Arguably if there was any ‘natural’ resistance to the ill effects of nCov19 exposure, populations with the most genetic diversity would hence, in theory, show reduced severity of covid19 and arguably, controlling for other factors, reduced CFRs. East Africa and then the Indian subcontinent are two such areas of tremendous genetic diversity.
I would wish to visit this page after 60 days to check where we are. I hope this is true.