Deadly epidemic outbreaks in the 20th and 21st centuries, number of deaths by type of virus. Graphic: The Guardian

Dr Jonathan D Quick
18 March 2018
(The Guardian) – Somewhere out there a dangerous virus is boiling up in the bloodstream of a bird, bat, monkey or pig, preparing to jump to a human being. It’s hard to comprehend the scope of such a threat, for it has the potential to wipe out millions of us, including my family and yours, over a matter of weeks or months. The risk makes the threat posed by Islamic State, a ground war, a massive climate event or even the dropping of a nuclear bomb on a major city pale by comparison.A new epidemic could turn into a pandemic without warning. It could be born in a factory farm in Minnesota, a poultry farm in China or the bat-inhabited elephant caves of Kenya – anywhere infected animals are in contact with humans. It could be a variation of the 1918 Spanish flu, one of hundreds of other known microbial threats or something entirely new, such as the 2003 Sars virus that spread globally from China. Once transmitted to a human, an airborne virus could pass from that one infected individual to 25,000 others within a week, and to more than 700,000 within the first month. Within three months, it could spread to every major urban centre in the world. And by six months, it could infect more than 300 million people and kill more than 30 million.This is not alarmist science fiction. It is one of several highly plausible scenarios – and far from the worst – developed by infectious disease specialists working with disease-modelling experts. Bill Gates, who funds a group that uses computer simulations to predict the spread of diseases, said: “The Ebola epidemic showed me that we are not ready for a serious epidemic, an epidemic that would be more infectious and would spread faster than Ebola did.” He put the likelihood of a catastrophic epidemic at “well over 50%” in his lifetime.Gates’s model estimates that a perilous virus, carried via cars, planes, ships, and trains, and spreading quickly in packed cities, could kill up to 33 million people in just over 200 days.In the last century alone, smallpox killed 300 to 500 million people. The 1918-19 Spanish flu killed 50 to 100 million and Aids has taken 40 million lives since it was first recognised in 1981. The annual influenza outbreak still claims half a million people a year worldwide. The west African Ebola crisis took more than 11,000 lives – seven times the total of the 22 Ebola epidemics that preceded it. But widespread death isn’t the only threat. For those who survive the initial infection, an epidemic leaves its own particular trail of disfigurement and disability. People who contracted smallpox suffered characteristic, sometimes horrific, scars, along with blindness, limb deformities and other disabilities. As a lifelong condition, Aids and the side-effects of treatment can affect nearly every body system, from brain to bone. [more]

Are we prepared for the looming epidemic threat?