Tuesday, March 3, 2020

Some cautionary notes on the coronavirus. It's both as bad as it seems and not as bad as it could be

In this Monday morning’s email from The Bulwark, Jonathan V. Last has some useful comments on how to view the coronavirus.

In a previous life I majored in molecular biology and spent some time interning in and around outcomes management and epidemiology, so I know a bit more about microbes and viral outbreaks than your average guy on the street.

We’ll have a piece at The Bulwark later this week by an actual doctor, but until then I want to make a couple points which I think are worth keeping in mind:

  • Don’t assume that Covid–19 is the beginning of the apocalypse.
  • Don’t underestimate the real damage that can be done by a non-apocalyptic outbreak.

What I’m really saying is: We should pay attention because this is serious stuff, but we shouldn’t either panic or whistle past the graveyard.

There are three important factors in any viral outbreak:

(1) The R0, or the basic reproduction number, of the bug. The simple way to think about this is: For every person who is infected, how many people do they pass the bug on to?

(2) The mortality rate for the bug. Which is to say, for every 100 people who get it, how many die?

(3) The geographic origin of the bug. This is important because if a virus originates in a rural, out-of-the-way location, the medical community has time to study it, figure out disease protocols, and possibly even contain it. By contrast, if it starts out near a dense population center that is highly connected, it can break out quickly leaving every [body] trying to catch up to it.

When you look at Covid–19 along these vectors, the news is mixed.

The R0 for coronavirus appears to be pretty high. We don’t know where it will settle but estimates are well about 2.0 and go as high as 3.5. Which means that the spread of the contagion is going to be very hard to stop.

That’s the bad news. The good news is that the mortality rate is relatively low. By “relatively” I mean that the mortality rate for Covid–19 seems to be in the neighborhood of 1 percent to 2 percent. My educated guess is that this number will decrease as we discover that more people have already had it. But let’s just leave it there for a minute.

Remember the ebola outbreak of 2014? Ebola’s fatality rate is upwards of 90 percent. So compared to that, Covid–19 is a walk in the park.

But only when compared to a monster bug like ebola.

Compared with other bugs, like the flu, where the mortality rate is closer to 0.5 percent, Covid–19 is much more dangerous.

And of course, the danger is not spread equally among populations. If you live in a developed country, you chances are better. If you are young and healthy, they get better still.

The problem is scale. If Covid–19 really does hit pandemic levels, then even a “low” mortality risk is going to kill a lot of people, especially among vulnerable populations, such as newborns, older folks, or people with compromised immune systems.

So while Covid–19 isn’t going to trigger an end-of-the-world zombie apocalypse—which is something ebola absolutely could have done—it could still cause a lot of misery and harm. Or it could burn out as the virus mutates in the wild.

All of which is to say that we should keep a careful eye on the situation, don’t assume the worst, but don’t assume the best, either.

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