A handful of Skittles

Here are my unfiltered, unedited thoughts on the virus and the lockdown.

Isn’t this just a bad cold?

No. Although coronaviruses do cause respiratory tract infections in humans, they’re not all the same. SARS was a coronavirus, as was MERS. In fact, the virus’s actual name is SARS-CoV-2.

OK, maybe it’s just the flu, then. After all, flu kills so many people per year and we don’t freak out about it.

Flu does kill thousands of Americans every year, and we do freak out about it. We’ve developed a vaccine for it — that’s how much we freak out about it. And this virus is worse! It’s more infectious than the flu (more on that below), and its mortality rate is 10–30 times higher than the flu. It hasn’t killed too many people in the US yet, because it hasn’t infected as many people as the flu has. Yet.

But still — this lockdown is an over-reaction. It tramples on my rights and it’s going to kill the economy.

To be fair, we’re not going to have much of an economy if we’re dead.

Still, here’s why this lockdown is important (you’ll forgive some nerdy, science-y things):

There are really only two fundamental numbers in an epidemic (ok, there are more, but these are the most important). The case-fatality rate, and the reproductive number (also called R0, R-zero, or R-naught). The case fatality rate for COVID-19 is currently sitting at 4.0% (link) — this varies by location. 4% in China, 8% in Italy, 0.3% in Germany. By comparison, the flu is 0.1%. Everyone thinks the 4% is a bit of an overestimate because there are likely lots of asymptomatic people with the virus, but most estimates predict that when everything dies down, the CFR will be 1–3%. (Hence 10–30 times higher than the flu).

That’s how many people die, but it’s not how the virus spreads. To understand that, you’ve got to look at the R0. Essentially, the R0 is “the number of new people an infected person infects.” See here:

The R0 for COVID-19 is around 2.5, higher than Ebola, and definitely higher than the flu.

This means that if I carry the disease, then I’ll infect 2.5 people on average. Those 2.5 people will infect 2.5 other people each, and so on…leading to exponential growth. Epidemics do not die down until the R0 drops below 1.

There are three ways you can drop the R0 below 1:

1. The virus mutates. (Waiting for that is kind of silly, so let’s ignore that one)

2. The virus simply runs out of people to infect — which is what it’s on its way to doing.

3. The virus just doesn’t encounter 2.5 people in the first place.

We basically have our choice, then, of letting the virus rip through the entire human population, or we force the R0 down to zero by keeping people away from each other. This is why travel bans and restaurant bans and quarantines have been implemented. If the virus doesn’t encounter someone to infect, then eventually its host fights it off and we’re good.

Evidence for this comes from the Diamond Princess, where they did the opposite of social distancing. They kept everyone on the ship. The R0 on the Diamond Princess was 15.

But aren’t most cases mild?

They are. According to the WHO’s guide to treat COVID, 81% of cases are mild, 14% require hospital admission, and 5% require ICU care (of which more than half die). So, the likelihood is that if you or I get this virus, we’ll be fine.

On the other hand, if I put 100 Skittles in a bowl and said, “20 of these will put you in the hospital and 3 of them will kill you”, would you grab a handful of Skittles?

The virus will die when the weather warms up, won’t it?

Our inimitable president claimed that this virus would “miraculously” go away when the weather warmed up in April.

And it’s true. Viruses are heat sensitive. Heat something hot enough and you’ll deactivate viruses. The problem is, April isn’t hot enough.

In fact, if summer killed this virus, then Australia wouldn’t have any of it. It does.

But I’m young, so I’m going to be ok. This virus infects old people

This is both true and false. The virus kills older and sicker people, for sure:

(The numbers from South Korea are a little less drastic than China, but even there the mortality in the over-80 age group is 8–10%).

But it doesn’t infect old people. It infects everyone — and probably young people more than old people. This next chart takes a little explaining:

The chart shows the age distribution of people who tested positive (not died) of the disease in Italy (green) and South Korea (red). If you just look at the Italy numbers, it looks like this is a virus infecting the elderly. But in SK, 50% of people who tested positive are under 40.

The difference is that Italy only tested symptomatic people (like the US is doing), whereas SK tested everyone. What this means is that the bulk of infections are asymptomatic infections in young people. Because the virus is infectious before symptoms show up, this means young people are carrying this virus to their older colleagues / family / friends — and then killing them.

We’ve got the best health system in the world. We can handle this if people get sick

Patently untrue. Whether or not we have the best health system in the world, our health system will be overwhelmed by this. We’ve only got about 100,000 ICU beds in the entire nation. Highest concentration of ICU beds per person anywhere in the world, but still, only 100,000. They usually operate at 90% capacity — meaning only about 10,000 ICU beds are open at any one time — because of things like strokes and heart attacks and cancer and the like. This is to say nothing of the PPE that’s needed (expected to run out in about 2 weeks), the doctors to take care of the ICU patients (Italy has had to pull in pathologists, who only ever see dead people, to take care of critically ill patients), the drugs necessary to keep people on a ventilator, etc. And people who need ICU care aren’t just on the vent for a day or two. They’re on for 7 days. Italy didn’t have the capacity to take care of their much smaller population, and neither do we of ours.

If we can keep the total number of cases down and we don’t have huge spikes — like we’re on our way to having — then our health system can cope. If we can’t flatten the curve, then we’re screwed. And the only way to flatten the curve is to drop that infernal R0.

But what about the UK? They haven’t closed things.

The UK are trying a different strategy to deal with this infection, which nobody thinks is smart (besides some dude on YouTube with his bucket). They intentionally want people to get infected in small doses so that you never overwhelm the health system. So the same idea behind rolling blackouts not to overwhelm an electrical grid. Then once people are infected, they’re immune, and voila — crisis averted.

Two problems with this: First, there’s evidence that infection doesn’t necessarily confer immunity. There are already multiple reports of people getting this a second time after they’ve recovered the first time. Spanish flu came in two waves — an earlier wave and a more lethal second wave. Everyone’s watching China to see if they get a second wave.

Second, we’re already having a hard enough time convincing people to Netflix and chill. How successful do you think it’ll be to tell people to Netflix and chill, and then when it’s their turn to grab a handful of Skittles and hope they don’t die?

A personal plea

Look, I get it. I don’t agree with infringing on individual rights either, and tanking the economy isn’t great. But those will recover before I will, before my friends will, before my colleagues will. In Italy, 16% of infections were among healthcare providers. Many of them died.

We know what we’re getting ourselves into. We made oaths to this. This is what we signed up to be doctors for. And we know that our friends will die because of this. We’re scared, but we’re doing it because this is why we’re here. We’re putting ourselves in actual harm’s way for you. Please stay home for us.

The stock market will get better. We might not.