Map of life expectancy at birth from Global Education Project.

Wednesday, January 22, 2020

Oh no! Are we all going to die?

Yes. However, very probably not because of the novel coronavirus that has appeared in China. This seems to be front page headlines in every media outlet on the planet, and  the World Health Organization has convened a meeting to decide whether to declare an official Global Health Emergency.

This sort of flapdoodle happens every time a novel pathogen appears. Back when I lived in the Hub of the Universe a mosquito-borne disease called West Nile virus appeared (having formerly been large confined to, yes, west of the Nile). For weeks, every time a new case was identified it would be on the front page of the Boston Globe. The Commissioner of Public Health sprayed Boston's residential neighborhoods with insecticide, killing of course every arthropod in the air column but probably not very many mosquitoes.

Now here's the thing about West Nile virus. The large majority of people who are infected have no symptoms at all, but derive life-long immunity. The vast majority of the rest have mild symptoms and probably think they just had a cold. They also derive life-long immunity. In rare cases, people develop meningitis, which even more rarely may go on to become serious causing permanent neural damage or death. Well, West Nile virus has no been in the U.S. for more than a decade and we've pretty much forgotten all about it because as public health problems go, it is utterly trivial. Far more people are seriously sickened or die from all sorts of other pathogens which we don't worry about at all, because it isn't worth worrying about, unless you happen to be one of the very unlucky ones.

So a reasonably sober assessment of the situation is here. According to the Chinese authorities, so far 17 deaths have been attributed to this virus, apparently all among people who were already sick and frail from other causes. (This happens to be true of most deaths attributed to influenza, BTW.) The Chinese have attributed 444 illnesses to the virus but that means the actual number must be far higher because most people just get a cold, don't show up for medical care, and don't get counted. That's what always happens with these outbreaks, of course. If, as some have estimated, there have actually been as many as 4,000 cases, then the case fatality rate is about 4.25 out of a thousand, which is pretty much in line with the case fatality rate for influenza. However, this virus appears to be much less transmissible and there is no reason to think it will become very widespread. (Previous coronavirus outbreaks known SARS and MERS fizzled out without much consequence.)

So why the mass hysteria? Well, public health authorities are always paranoid about novel pathogens because some pretty bad things have happened in the recent past -- HIV, Zika -- and in the more distant past, the Black Death, which killed something like half the population of Europe; and the smallpox and other epidemics that largely wiped out the indigenous people of North America. Nowadays we know a lot about viruses and we can identify and classify them and combat them effectively enough that it seems unlikely anything like the Black Death will happen, but nobody wants to find out the hard way so they tend to be hypervigilant. Which I suppose is a good thing. But let the assigned paranoiacs worry about this one. We'll let you know if and when you need to start worrying.

1 comment:

Dr Porkenheimer said...

Yeah, it's kinda creepy when I think of all the street food I ate in Wuhan. But that was a couple of years ago. Still...