National Post (National Edition)
LETHAL VS. DEADLY
Wuhan, once the centre of the COVID-19 pandemic, now reports zero COVID cases, and life is slowly going back to normal. This isn't the case for the rest of the world. Countries and cities are going in and out of lockdowns, as cases climb and fall, over and over again.
The virus is projected to kill 1.8 million people worldwide by the end of the year. As of 7 p.m. Tuesday, there have been 15,313 deaths in Canada. The numbers change hourly.
And while early reports on fatalities from the virus out of Wuhan, and then Italy and New York, were alarming, the death rate is much lower than it was at the beginning of the pandemic.
“It's very misleading to discuss the overall case fatality rate because there is so much variability between populations and age groups,” Miller said. The COVID-19 death rate of older people compared to that of younger people is very different.
Miller said that even comparing healthy and active elderly people to frail elderly people isn't possible.
Despite the sheer numbers of people who have succumbed, COVID-19 is not as lethal an infectious disease as one would think.
SARS-1 was more deadly – it had a one-in-three chance of killing infected people — but it didn't kill nearly as many people as COVID-19 has.
The reason? More lethal viruses tend to kill their hosts before they can spread from one person to the next.
“It tends to be the case that viruses that cause really, really high death rates are not well adapted to spread in humans,” Miller said.
Because COVID-19 is capable of spreading and thriving in the human body, it is also more contagious and more adept at transmission through the population.
So, less lethal does not necessarily mean less deadly for humanity, according to anthropologist and cognitive scientist Samuel Paul Veissière, as reported by the National Post's Sharon Kirkey back in March. “We should pause to remark that COVID-19 is extraordinarily successful epidemiologically, precisely because it is not extremely lethal,” Veissière, an assistant professor of psychiatry at McGill University, wrote in Psychology Today. Ebola, by contrast, “is a rather stupid virus: It kills its host — and itself — too quickly to spread far enough to reshape other species' life-ways to cater to its needs.”