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The aliens among us

     Humans think of themselves as the world’s apex predators. Hence the silence of sabre-tooth tigers, the absence of moas from New Zealand and the long list of endangered megafauna. But sars-cov-2 shows how people can also end up as prey. Viruses have caused a litany of modern pandemics, from Covid-19, to hiv/aids to the influenza outbreak in 1918-20, which killed many more people than the first world war. Before that, the colonisation of the Americas by Europeans was abetted – and perhaps made possible – by epidemics of smallpox, measles and influenza brought unwittingly by the invaders, which annihilated many of the original inhabitants.

(www.economist.com, 22.08.2020. Adapted.)