COVID-19: Should we worry?

COVID-19 is still in its young days, but historical trend is comforting

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Coronavirus, as it continues to sweep from one continent to another, is professed as the greatest threat to humanity. Our generation is not really used to seeing the destruction by a global pandemic. We thought mankind is much ahead of the deadly reach of a virus. Advancements in science and technology gave us a false sense of security. The fact remains that nanometric-sized bugs have been our greatest enemies from the days when we were cave-dwellers. Globally, infectious diseases have claimed more lives than all the wars combined. They have wiped out civilisations, stopped invasions on its tracks, spurred revolutions, and have created empires. History, as we see today, was in-parts written by these tiny, invisible creatures.

Indian history is also influenced by a global pandemic which consumed 12-18 million of its total population within a short span of three months, way back in 1918. The world called it ‘Spanish Flu’. It claimed around 100 million lives worldwide, and India was the worst affected. History has not given due importance to this episode, mainly because it occurred in an eventful era of World War-I, and more so because the devastation happened in a colonial country.

Despite historians dubbing it as ‘yielding a relatively poor historiographical harvest’, there is ample evidence to prove that the Spanish Flu was ‘the greatest pandemic in world history’. It struck at a time when India was just coming out of its fight against plague, smallpox, cholera, malaria and typhoid. The economic situation of India was under severe stress when close to a million of its men had to participate in World War I for the British Empire. Famine and malnutrition were severe, fuelled by the wartime economic crisis and the unfavourable seasons. The pandemic got a transit across the globe with troop movements. It is believed that the flu reached India when troopships from Basra (Iraq) came to Bombay and Karachi.  The first wave of flu was comparatively milder which only affected children and elderly with lower mortality. The second wave was deadlier than the first, predominantly affecting younger age groups. Punjab, Madras and Bombay were among severely affected regions.

The Spanish Flu was later identified to be caused by H1N1 influenza-A type virus. Through a process termed genetic re-assortment, viruses that specifically affect one species can genetically evolve to be capable of affecting another. Possibly, such a process facilitated transfer of genes from avian infecting virus to a swine infecting virus that could infect humans.

Normally, we slip back into the ease of complacency and forgetfulness once an epidemic ends. But, history never forgets to repeat itself. Separated by a century, yet another pandemic strikes. The year 2020 woke up to the terror of COVID-19, caused by a virus officially named as Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). The virus has got protrusions from its body which makes it look like a crown in 2D electron microscopic images. ‘Corona’ refers to crown/halo in Latin and hence the name. These protrusions are called spike proteins and it gives ability for the virus to attach to and enter a host cell. Coronavirus was considered rather harmless till the dawn of the millennia. But, in 2003, Coronavirus struck the first major epidemic of the 21st century, which was termed ‘Severe Acute Respiratory Syndrome’ (SARS). In 2012, Corona virus unleashed yet another epidemic- ‘Middle East Respiratory Syndrome’ (MERS). Both the epidemics could be controlled before turning into a pandemic.

The current COVID-19-causing virus is considered to have emerged from bats and is genetically evolved to be more infectious than its predecessors. Studies indicate that genetic changes have super-powered the spike proteins of the COVID-19 virus. SARS viruses usually latch onto ACE-2 protein (Angiotensin-Converting Enzyme 2) present on the surface of cells which lines the human respiratory tract. Studies indicate that the COVID-19 spike proteins are up to 20 times more efficient in binding to the ACE-2 proteins compared to its predecessor. A second key genetic change allowed the coronavirus to grow a flap upon the spike protein that is tailor-made to be cut by a molecular scissor Furin, which is abundantly present in the lung and throat cells. This cut will help the entrance of the virus into host cells. Specific details are yet to come out, but it is clear that COVID-19 is much better armed to spread itself when compared to predecessors from the corona family. 

Beacon of optimism

Despite the fact that we have been threatened frequently by pandemics throughout history, we are getting better at dealing with it, and the trend shows that mortality is gradually coming down. COVID-19 is still in its young days and its future cannot be precisely predicted. But the trend from history is comforting. Though a pandemic of this scale tests the resilience of mankind, it is not here to stay forever. So far, mankind has survived all pandemics and epidemics nature has thrown at it. The causative virus can undergo genetic mutations with time, which may curb its lethality, as endorsed by the case of the Spanish Flu. Spanish Flu had claimed 4,597 lives in Philadelphia in the span of a week by October 16, 1918, and by November 11, the cases dropped to nil; possibly suggesting a rapid genetic change in the virus, rendering it less lethal. Or a vaccine may soon be discovered against the virus. Just like any other pandemic/epidemic that has ever affected mankind, COVID-19 possibly will also thin out and vanish; but not before drawing a line of demarcation in world history between ages before and after it.

Manu Krishnan K. is a researcher in Amrita Centre for Nanosciences in Kochi.