Update: Most information presented here is out of date. See the 80,000 hours page for more up-to-date information.
I have been researching the Wuhan Coronavirus for several hours today, and I have come to the tentative conclusion that the situation is worse than I initially thought.
Given my current understanding, it now seems reasonable to assign a non-negligible probability (>2%) to the proposition that the current outbreak will result in a global disaster (>50 million deaths resulting from the pathogen within 1 year). I understand this prediction will sound alarmist, but in this post I will outline some of the reasons why I have come to this conclusion.
I now believe that it is warranted for effective altruists to take particular actions to prepare for a resulting pandemic. The most effective action is likely to research preparation in order to limit exposure to sources of the virus. Sending out evidence-based warning signals to at-risk communities may also be effective at limiting the spread of the pathogen.
Summary of my reasons for believing that this outbreak could result in a global disaster
- The current outbreak matches the criteria that scientists have identified as being particularly likely characteristics of a pandemic-induced global disaster. That is, it’s a disease that’s contagious during a long incubation period, has a high infection rate, has no known treatment, few people are immune, and it has a low but significant mortality rate. See this article for a summary of likely characteristics of a pandemic-induced global disaster.
- Based on my research, I wasn't able to identify any historically recent pathogen with these characteristics, giving me reason to believe that using an outside view to argue against alarmism may not be warranted. For reference, the 2003 SARS outbreak, the 2009 Swine Flu, and the several Ebola outbreaks do not match the profiles of a global disaster as completely as the current outbreak.
- Estimates of the mortality rate vary, but one media source says, "While the single figures of deaths in early January seemed reassuring, the death toll has now climbed to above 3 percent." This would put it roughly on par with the mortality rate of the 1918 flu pandemic, and over 10 times more deadly than a normal seasonal flu. It’s worth noting, however, that the 1918 flu pandemic killed mostly young adults, whereas the pattern for this pathogen appears to be the opposite (which is normal for pathogens).
- The incubation period (the period during which symptoms are not present but those infected can still infect others) could be as long as 14 days, according to many sources.
- An Imperial College London report stated, "Self-sustaining human-to-human transmission of the novel coronavirus (2019-nCov) is the only plausible explanation of the scale of the outbreak in Wuhan. We estimate that, on average, each case infected 2.6 (uncertainty range: 1.5-3.5) other people up to 18th January 2020, based on an analysis combining our past estimates of the size of the outbreak in Wuhan with computational modelling of potential epidemic trajectories. This implies that control measures need to block well over 60% of transmission to be effective in controlling the outbreak."
- Compare the above infection rate to the H1N1 virus, which some estimate to have infected 10-20% of the world population in 2009. The World Health Organization has said, "The pandemic (H1N1) 2009 influenza virus has a R0 of 1.2 to 1.6 (Fraser, 2009) which makes controlling its spread easier than viruses with higher transmissibility."
- A simple regression model indicates that the growth rate of the pathogen is predictable and extremely rapid.
- The number of cases as reported by the National Health Commission of China forms the basis of my regression model (you can currently find the number of cases reported in graphical format on the Wikipedia page here). An exponential regression model fit to the data reveals that the equation 38.7 * e^(0.389 * (t+11)) strongly retrodicts the number of cases (where t is the number of days since January 26th). In this model, the growth is very high.
- [Update: Growth for January 27th remained roughly in line with the predicted growth from the exponential regression model. The new equation is 35.5*exp(0.401*t) where t is the number of days since January 15th]
- A top expert has estimated that approximately 100,000 people have already been infected, which is much more than the confirmed number of 2808 (as of January 26th). If the number were this high, then the pathogen has likely already crossed the quarantine. The infection has also spread to 12 other countries besides China, supporting this point.
- The Metaculus community’s estimate for the number of total cases in 2020 is much higher than it was just two or three days ago. Compare this older question here, versus this new question (when it opens).
- While several organizations are developing a vaccine, Wikipedia seems to indicate that it will take months before vaccines even enter trials, and we should expect that it will take about a year before a vaccine comes out.
Summary of my recommendations
I think it's unlikely that EAs are in any special position to help stop the pandemic. However, we can guard ourselves against the pandemic by heeding early warnings, research ways to limit our exposure to the virus, and use our platforms to warn those at-risk.
The CDC has a page for preparing for disaster.
Currently, the pathogen appears to have a significant mortality rate, but kills mainly older people. Therefore, old people are most at-risk of dying.
Even if you contract the disease and don't die, the symptoms are likely to be severe. One source says,
ARDS (acute respiratory distress syndrome) is a common complication. Between 25 and 32 percent of cases are admitted to the intensive care unit (ICU) for mechanical ventilation and sometimes ECMO (pumping blood through an artificial lung for oxygenation).
Other complications include septic shock, acute kidney injury, and virus-induced cardiac injury. The extensive lung damage also sets the lung up for secondary bacterial pneumonia, which occurs in 10 percent of ICU admissions.
Acknowledgements: Dony Christie and Louis Francini helped gather sources and write this post.
For a week or so I have been fearing this potentially deadly disease spreading to most people on Earth (space-station and antarctic bases excepted), since the doubling time has been about half a week, and simple calculations show that even with a 1 week doubling time, half the Earth's population would get it by June. My fears were confirmed by reading of the John Hopkins Event 201 simulation last year, in which a 1 week doubling time virus spread throughout the world and killed tens of millions of people:
https://www.abc.net.au/news/2020-02-01/coronavirus-outbreak-researchers-simulated-severe-pandemic/11906562
http://www.centerforhealthsecurity.org/event201/videos.html
There is no precedent for a virus spreading as fast and far as this one:
https://graphics.reuters.com/CHINA-HEALTH-VIRUS-COMPARISON/0100B5BY3CY/
I still believe the Wuhan coronavirus will infect half the population by the middle of this year, but I now have cause for hope that the variants which do this will be far less virulent than the one or ones which caused the deaths in Hubei in January.
I am not an epidemiologist, but here goes. I am suggesting that the virus is mutating rapidly into less virulent strains which compete successfully against the original, December and early January, more virulent form(s). However, I know of no reports of such mutations.
From the John Hopkins ticker (necessarily long URL):
https://gisanddata.maps.arcgis.com/apps/opsdashboard/index.html#/bda7594740fd40299423467b48e9ecf6
here are the figures from Hubei, the province containing Wuhan, and the ten provinces with the highest death rates, all of which were infected in mid to late January, about 5 or 6 weeks after the disease began in Wuhan. (The following is a table, to be viewed in a fixed width font.)
The lower death rate in the provinces which were first infected well after the initial spread in Hubei is striking: it is 1/27th the death rate in Hubei.
The reasons for this might include:
1. Cases in the other provinces are, on average, more recent than those in Hubei, meaning the death rate will rise over time to resemble that of Hubei (and the Hubei death rate could rise too, for the same reason.)
2. Saturation of hospitals and testing in Hubei and Wuhan in particular.
3. The provinces being infected more with a less symptomatic and so less deadly variant of the virus than those which caused the initial spread in Hubei, though hopefully the same process would be occurring in Hubei too, so the death rate for recent infections would be lower too. (I hope this is happening.)
4. Nursing leading to people surviving to the extent that a significantly lower proportion of people have no immunity. (I think this does not yet play a significant role.)
5. Poorer quality of care, including people not being able to get into hospital, in Hubei compared to the other provinces
However, I can’t imagine that 1, 2 or 4 would make anything like the difference we see - a striking 27:1 ratio in the death rate. 5 might explain some of it. This makes me think that 3 is true to a significant degree.
Now turning to the recovery rates. The other provinces have a significantly higher recovery rate than Hubei. Assuming the diagnostic standards do not vary significantly, this cannot be explained by 1, 2 or 4. It would be very well explained by 3.
In the other provinces, the recognised infections seem to be less damaging, with quicker recovery. Assuming that quality of care is about the same, the only explanation I can think of is that these more recent cases in the other provinces are with variants of the virus which cause less symptoms and perhaps lead to an earlier recovery - while still being contagious enough to compete successfully against the original and/or any more recently mutated, more virulent strains.
This analysis gives me hope that by the time the virus reaches about half the people on Earth - as I believe it will by the middle of this year - that the variants most people get will be much less damaging than at the start of the pandemic.
If this analysis is true, then the true rates of infection in the other provinces - and recently in Hubei - may be much higher in proportion to the number of confirmed cases than was the ratio a few weeks ago. This would be due to a greater proportion of infected people having no or only mild symptoms - so they are never tested or recognised much by the medical system.
If this is occurring, then it may work out well . . . unless there are mutants which remain highly infectious but which have sufficiently different spike and envelope proteins that the antibodies developed in response to the current strains are ineffective. Then those strains might start a whole second wave of infection, since immunologically, they would be a different virus.
If this analysis is correct, then while the Chinese lockdown (which is unsustainable) may slow the spread of the virus more effectively than the post-symptom quarantine arrangements of the West (which is the best they can do, not being a dictatorship), the Western approach is actually more helpful. This would be due to the Western approach enabling strains of the virus which have few or no symptoms to spread very rapidly, while significantly reducing the replication of strains which produce strong enough symptoms for people to be hospitalised and tested.
If there were no such helpful mutations, then the Western approach would be less effective than the Chinese approach, but the Chinese approach is unsustainable for more than a few weeks. There's no hope of a conventional vaccine by the middle of this year, or even the end. However, if my analysis is correct, then by the good fortune of the virus mutating without altering its envelope and spike proteins significantly, the most successful strains become less damaging and work like a vaccine against the more damaging strains.