My friends, church leaders and workplace take COVID-19 quite seriously and have made drastic moves towards social distancing, so I thought it was time to shift towards figuring out how best to cope with the new reality – until I ran an errand and saw how many people are still out and about. Yesterday I went out to the library to return our books before they go overdue, and was horrified to see how crowded it was. On the way, I passed by the playground in our neighborhood, and it was busy with kids and families playing together. Some of my contacts on Facebook also mentioned that they haven’t changed anything voluntarily, and recommended going on with life as normal except for avoiding large crowds and doing extra handwashing. This is dangerous, and I want to explain why. For a visual illustration, check out this Washington post simulator where you can see the effects of different containment strategies.

“Minor” illnesses still kill large numbers of people, making COVID-19 especially concerning

Folks argue that COVID-19 is minor, just an overhyped flu or cold, but it’s likely to be far more serious because no one is immune so it can spread through our whole population and the death rates are higher. Still, let’s run with that idea for a moment – what if it were just an overhyped “normal” virus?

Two years ago, my youngest daughter had RSV and nearly died – or at least, she would have died if she hadn’t been in the ICU. Pretty much all kids get RSV before they are two, and for most it’s not severe, but occasionally it requires medical attention – in about 5-20% of cases, similar to COVID-19. She was one of those, and ended up needing to be on oxygen in the pediatric ICU for a couple of days while she fought it off. However, she hated the breathing devices and at one point while I was holding her, she managed to rip off her oxygen device (cannula) and break it. Watching her look of terror as she turned purple in my arms from lack of oxygen as I shouted for help was one of the most horrifying experiences of my life. She would have died right there in my arms while I watched if she’d not had appropriate medical care. Fortunately, she was in the ICU, got the right care, and was back home feeling normal again in about 24 more hours.

When she was in the pediatric ICU, most of the other kids there – and there were a lot – were there with similar issues because of flu and RSV. Until that time, I’d never gotten flu shots regularly because I thought, “What’s the big deal? It’s just something which makes you sick for a few days.” But after this experience, I realized that I ought to get flu shots regularly – not for me, but for the at-risk folks who I might infect if I were to get the flu. I don’t want to kill someone else’s one-year-old or grandmother because I thought it wasn’t worth my time to get a flu shot. And that’s what I’d be doing, without even knowing it. Love for my neighbor, I now believe, means I need to take action to help protect vulnerable people around me.

The parallel to RSV is interesting, because RSV seems to result in a similar fraction of hospitalizations to COVID-19 (though mainly for children) and also has a relatively low mortality rate– less than 1%. Still, in some cases it is severe. There are key differences, though; for example, no one in our population is immune to COVID-19, it spreads rapidly, and has a very high death rate for some fractions of the population.

So, even if this were just a normal virus like the flu virus or RSV, we should take drastic action. It looks like death rates are likely 0.5-5% when averaged across age groups, depending on medical care. If it spreads through, say, 40% of the US population of 300 million, a 0.5% death rate would be 600,000 deaths.

How much of a difference can I make? A lot.

In an epidemic, each person infected may infect others, meaning each of us can have a huge impact. Early estimates for COVID-19 before controls indicated that, in the absence of social distancing measures/lockdowns, each person infected 2 to 2.4 other people. That doesn’t sound like a lot, except then each of those people infects 2-2.4 other people as well, and so on, for many cycles.

This means each of us can have a major impact. If I infect two people, then each of them infect two people, and so on, for eight cycles, then I’ll be responsible for 256 people having the disease. At a 0.5% death rate that works out to about one death. If the death rate is closer to 5%, I’d be responsible for the death of 12 people. But that goes up the more cycles there are, with the number of people doubling every cycle.

The death rate doesn’t look like it’s going to be below 1%, from what we can tell:

Earlier in the epidemic, there was hope that 3.5 percent was grossly overestimated, however as evidence continues to emerge, there is dwindling support for that hope.

Likewise:

This is what you see in the data. China’s fatality rate is now between 3.6% and 6.1%. If you project that in the future, it looks like it converges towards ~3.8%-4%.

Distancing measures and staying home are critical because they reduce the number of people infected per illness, e.g. China’s restrictions brought that number down from 2.35 to 1.05; a number of 1.05 means that it still spreads, but only very very slowly.

Staying home when sick isn’t the solution

Folks can spread the virus before they show symptoms or it can be so minor that they don’t realize they have it. So, staying home when sick isn’t the solution. To keep it from spreading rapidly, we need to reduce our contact with other people.

Because of this, my family opted to stay home from church today and live stream the service, even though church is very important to us – more so than almost anything else. If we were faced with the possibility of a terrorist attack on our church, we would go and worship anyway, because it’s that important to us – more so than staying alive. But this is different; by staying home, we care for other people. As we see it, it’s not just about us – it’s about the people we might unintentionally sicken by going.

It’ll be slow at first, until it’s not

Currently in my area, people are starting to take drastic measures – though as I noted about the playground and library, perhaps not drastic enough. Still, I worry people will fatigue of these measures as they get lonely and bored, especially as the situation may not seem to be changing that rapidly. Indeed, it’s not – the doubling time (which may change) seems to be around six days (though one of my grad students, using the latest CDC data, is coming up with a number closer to four days). Six days can be a lot of loneliness and isolation, and in today’s nonstop news cycle it can seem like an eternity.

Still, the same math from above applies. At first it might just be one person in a thousand sick, then two, then four, then eight, 16, 32, 64, 128 and so on… The number starts small but gets bigger quickly.

So what should you do?

Cancel everything social and move it online, unless you must do it. If you’re a police officer, firefighter, healthcare, healthcare worker, etc., or responsible for our foodchain or other essentials, then by all means keep doing your job but maintain as much social distance as possible. But otherwise, move things online. In my next post I’ll provide some links to resources that may be helpful for folks to move things online.

Still, from what I understand, we shouldn’t be afraid to go outdoors – as long as we maintain appropriate distance and avoid touching “public surfaces”. My kids (and I) will go nuts without physical activity; I took some of them with me on bikes yesterday while I ran for a few miles. Most of them swim quite a bit every day, but that’s now canceled, so there’ll likely be a lot more running and bike rides.

Tell your friends. There are still lots of people out there who think this is no big deal, and are going on with life as normal, or think everyone is overreacting. Let’s try to help our friends understand what’s going on, and how much of a difference each person can make.

Let’s also try and find ways to help others; there are some who aren’t going to be able to go out at all, even to shop – especially those who are at risk. Check out how this woman helped an elderly couple who was afraid to shop. There are going to be lots of needs; let’s help meet them.

Further reading

Thomas Pueyo’s piece is still one of my favorites; it’s been updated to discuss the difference between containment (which will no longer work in the US) and mitigation, which is the stage we’re in now. See this:

Mitigation requires heavy social distancing. People need to stop hanging out to drop the transmission rate (R), from the R=~2–3 that the virus follows without measures, to below 1, so that it eventually dies out.

Flatten the Curve is a good read to understand how the virus is already here and what we do now really matters, and that our actions can have a direct impact on the overall death rate.

If you want direct access to a dashboard to visualize the latest data, check out the Johns Hopkins Coronavirus Resource Center.

If you like math and analysis, Jason Warner’s long facebook post provides a useful analysis. It’s a long read, but deals with the key issues. A couple highlights:

I have already isolated my family. We have canceled EVERYTHING. We have canceled previously scheduled doctor visits. Social get togethers. No play dates. Normal routine meetings. Everything has been canceled. It’s difficult and socially awkward. Some of you think I’m crazy, but I’m doing it not because I am afraid, but because I am good at math

If hand washing and “being smart” were sufficient Italy would not be in crisis.

Spreading the virus puts those in the high-risk category at much greater risk. This is the moral argument. It’s a strong argument because there are only two ways, as of today, that the virus can be stopped: let it run its course and infect 100s of millions of people, or social distancing. There is no other way today. If you don’t practice social distancing, people downstream from you that you transmit the virus to will die, and many will suffer.

The virus is already in your town. It’s everywhere. Cases are typically only discovered when someone gets sick enough to seek medical attention. This is important as it typically takes ~5 days to START showing ANY symptoms. Here’s the math: For every known case there are approximately 50 unknown cases… in the time it takes me to figure out I am sick 50 others downline from me now have the virus. So every third day the infection rate doubles until I get so sick that I realize I have the virus an am hospitalized or otherwise tested. Harvard and Massachusetts General Hospital estimate that there are 50x more infections than known infections as reported.

This might seem implausible, but think about it this way: What if you have a cough and a sore throat right now, probably a cold that you caught a few days ago? If it’s COVID-19 and you’ve had it five days, you’re now starting to show symptoms. In a few more days, perhaps you might begin feeling sick enough to go to the hospital and get tested – or perhaps it’ll just go away and you’ll never even know if you’ve had COVID-19. Only if you actually (a) get really sick, and (b) go get tested (once testing catches up) will we find out that you had it. Otherwise, you don’t even show up in the statistics. And even if you do, it’s not until long after you actually caught the virus. So it’s easy to see how the number of reported cases could be 50x lower than the actual number.

Currently Johns Hopkins is showing 3200 cases in the US – again, from very ill people – which likely means we have well over 160000 cases around the country.

Other posts in this series: