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Journalism of Courage
Humans constitute a miniscule part of life on Earth. But to most of us, it takes a disease or a natural catastrophe to show humans their place in nature’s scheme. The pandemic has been one such humbling experience. On more than one occasion, we have felt victory against the SARS-CoV-2 virus to be close at hand, only for the microbe to prove us wrong. The past two years have shown that despite the remarkable scale of scientific accomplishments, much about the ways of microbes remains in the realm of the unknown. And, viruses are among the least understood of pathogens.
All viruses, however, are not oracles of disease. In Invisible Empire: The Nature History of Viruses, Pranay Lal shows how viruses are integral to human life and they have been critical in making us what we are. Not, just human evolution. The transformation of the tulip from an object of beauty to a commodity of speculation and desire, for instance, owes much to the artifice of a virus. Invisible Empire is a fascinating piece of work that tries to understand these simplest life forms – “mostly dozens of genes wrapped in a coat of protein” — as well as excavate the human endeavours to unravel the mysteries they present. Viruses are inert till they find a host to multiply. Then, they undergo a transformation of sorts to lead complex and diverse lives.
Part of the failure to understand viruses stems from, as Lal points out, from the human fascination with large charismatic creatures. For long, taxonomists tried to slot them according to the traditional seven-rank system only to find out that the complexity and diversity of virosphere eludes the kingdom-phylum-class-order-family-genus-species schema. It was only in 2020 that the International Committee on the Taxonomy of Viruses expanded the criteria to a 15-rank system.
Invisible Empire maps two seminal developments in the endeavour to understand viruses. It first locates virology within the broader field of understanding microbes. For long – and somewhat predictably, given the human propensity to understand the relatively larger life form better — viruses were not thought to be much different from bacteria. Louis Pasteur, though he found a vaccine for rabies, had not even looked closely at the pathogen that caused disease. The quest to understand the causes of infection in tobacco plants, foot-and-mouth disease in cattle and yellow fever along with the development of powerful microscopes contributed to identifying viruses as distinctive life forms. In 1939, a year after the first “proper” electron microscope was launched, a crystal of the tobacco mosaic virus was placed under it. The ‘TMV” was the first virus to be seen by us.
The other major development happened as late as 2003. The Human Genome Project found entire sequences of RNA viruses, retroviruses, embedded within our genes. In one of the most riveting sections of Invisible Empire, Lal shows how acquiring a retroviral gene was a momentous development for all modern mammals. It’s a retroviral infection in reptilian mammalian ancestors, for instance, that stops the mother’s immune system from attacking a developing embryo which it can mistake as a foreign body. In the nearly two decades since the Human Genome Project, scientists have identified more than 50 Human Endogenous Retroviruses (HERV) that were critical to human evolution such as our transformation from hunter gatherers to sedentary farmers.
At the same time, HERVs may even be responsible for certain kinds of cancers and inflammatory diseases. Some of them may lie dormant for long periods and then get awakened by environmental triggers. “If Charles Darwin reappeared today, he might be surprised that humans descended from viruses as well as from apes,” Lal quotes biologist Robin Weiss telling The New Yorker. Weiss was amongst the first to discover ERVs in wild fowl and chicken.
The virosphere is critical in other ways. Along with other microbes, viruses regulate the activities of carbon, phosphorus, nitrogen and sulphur – the building blocks of life. They also prevent fellow microbes from becoming hazards.
Lal doesn’t neglect the other side of the story. Invisible Empire alerts us to the depredations caused by viruses. Some, such as smallpox or the HIV and ebola in more recent times, are well known. But the brilliance of Lal’s prose makes a tour to these often-visited episodes interesting, and one often comes back with fresh insights. Our attention is also drawn to diseases that no longer take a toll – the sweating sickness virus, for instance, struck in the 16th century in England, lay dormant for a century and half, before appearing in 1718 in France and Spain and then vanishing forever around the second half of the 20th century.
At other times, Lal corrects us for using terms such as critters, germs, pests casually. When seen in the context of nature, there can hardly be any bugs. Not surprisingly, the book is replete with words that would be essential to a dictionary of science jargon. But it says something of Lal’s demystifying skills that the reader’s curiosity is only whetted on encountering such terms. Invisible Empire is one of those books that you read cover-to-cover, parts of it become favourites, and you keep going back to them. For this reviewer, the book has several – the struggle to find the origins of viruses, how these microbes got embedded in our genes, friendly microbes, antibiotic resistance, the story of tulips.
Lal’s is also an argument for an “anthro-pause”. For too long “we have been looking at ourselves, our existence, our relationship through a keyhole, from our perspective alone,” he writes at one point. This shouldn’t be mistaken for biological determinism but a plea to appreciate that we share space with microscopic creatures that behave in complex ways – benign, creative, and destructive. The pandemic should alert us to, as Lal says, the “need to understand that our bodies are an ecosystem… Every pathogen that affects us has its own set of pathogens – the enemy’s enemy…The revival of a safe and responsive public system to address disease will depend on how well we understand the ecology of viruses and the human microbiome in the context of disease and wellness”.
