We actually know quite a bit about this epidemic. We know the death rate is on the order of 1%, or at least 0.5% to 2%. We know it grows exponentially if left unaddressed. We know that this would eventually overwhelm the hospital system, causing massive death among people who don’t even have coronavirus. We know that most societies won’t allow that to happen and we know that it’s possible to prevent that outcome. So what are the big unknowns?
1. How long until a vaccine, or some other treatment?
2. What’s the tradeoff between economic harm and epidemic control, until we get a vaccine?
China is likely to provide the first test on the second question. Here’s Bloomberg:
“This coronavirus is more comparable to influenza,” said Ben Cowling, a professor of epidemiology at Hong Kong University, who said it might take two months for fresh cases to emerge in China. “It spreads too easily, and most parts of the world don’t have the ability like China to do containment and control to get rid of it.”
China had no new domestic cases yesterday, for the first time. It is still getting a few dozen new cases from international travelers, which are all quarantined for 14 days on arriving in China. So it seems that domestic community transmission can be controlled.
One obvious question is whether other (less authoritarian) countries will also be able to put a lid on community transmission. I don’t know the answer to that, although based on what we see in other East Asian counties, I’d say “to some extent, but perhaps less so than China.”
But first I’d like to consider a different question—the prospect for China itself. The above reference to the virus popping up again in two months may sound like bad news, but it actually is not. I presume that China has the following strategy in mind:
Continue quarantining inbound flights. Even so, some cases will leak across the land border. Each time a new domestic case is discovered, they’ll clamp down on that region hard, just as they did with Hubei province. The hope is that life can go on as usual in provinces not directly affected. Rinse and repeat until a vaccine is developed.
Normally, I’d be rather pessimistic about this strategy. But there are two facts that suggest it just might work. First, a new outbreak would likely be far less severe than the Wuhan outbreak was when the Chinese government finally got around to addressing it. Thus the new round of tight controls would tamp down on things much earlier than in Wuhan.
Second, the response to the severe outbreak in Wuhan achieved success amazingly quickly. Thus the second round of controls would probably be effective even more quickly. China has learned a lot in the past 3 months. I could see China having 5 or 10 such local clampdowns between now and the time a vaccine is developed, but still keep their economy functioning.
I am less optimistic about countries outside of East Asia. Experts still don’t fully understand why new infections in East Asia are so low. Some smaller countries seem to have effective policies. But Japan does not, and still seems to have a low rate of new infection (although some question the Japanese data.)
I do know that East Asians were much more likely to wear masks even before the epidemic, and this article says the Japanese wash hands more often and touch each other less often than do Westerners (less hand shaking, etc.) Yet it seems odd these factors would be decisive, given crowded subways in Japanese cities.
I think Tyler Cowen is exactly right when he suggests that if we tried the herd immunity approach then the hospital system would become overwhelmed, we’d freak out, and then we’d abandon the strategy at a time when it was too late to easily control the epidemic. But he also points out that social distancing is hard to maintain in a Western society, and suggests a possible yo-yo-ing of policy. The question is whether there’s some amount of social distancing that is consistent with less than a deep depression, but holds the R0 down below 1.0, say to 0.8 or 0.9. And what amount of social distancing is that?
That’s the 6.4 trillion dollar question, and I have no idea what the answer is.
PS. This video suggests that one difference between the East and West is that East Asian countries revamped their public heath systems after the SARS epidemic, to be ready for the next one. The West did not. Ironically, they have many more hospital beds than the US (per capita) despite spending much less on health care. They are far more prepared than we are.
Think of “country immunity”. Once a country has been infected by a major epidemic, it creates institutional “antibodies” making it less susceptible to the next one.