One of my major frustrations with the “news” media is how they treat numbers. In a situation like we are facing with the COVID-19 outbreak, the data is very fuzzy, and we are apparently seeing wild swings in the numbers. Headlines like this one in the New York Times are facing folks as they wake up this morning: Cases and deaths surge in Italy as its north is locked down. So we should panic, right? Maybe not.
As previously noted, I’m using data from the nCoV-2019 Data Working Group data base, Epidemiological Data from the nCoV-2019 Outbreak: Early Descriptions from Publicly Available Data as well as the current (9 March 2020) World Health Organization database. I’m also indirectly using other sources of information to cross check these data.
If we look at China, which seems to be stabilizing, it seems the all population hospitalization rate (sick enough to present for medical care and require hospitalization) for COVID19 is about 0.14 percent. Do we believe that number? I think so. The number for Korea is about 0.15%. The number for the Diamond Princess cruise ship, adjusted for demographics, is about the same. Iran and Italy are still below that (0.07% and 0.05% respectively), but are still increasing day by day and are a several weeks behind Iran and Italy.
So we can have some confidence that the fraction of the total population that will get sick enough to need medical care is 0.15 to 0.25 percent. That is what the numbers in China and Korea are converging on. For reference, the 2017 H3N2 outbreak had an overall rate of between 0.25% and, for the unvaccinated fraction of the population, 0.39%. So for the overall population this is a lot like a bad influenza outbreak. It does have some differences (it is moving faster, and it impacts various populations differently) but the overall number isn’t statistically different for the average person.
Given the above, I expect that the Italy numbers still have significant “upside” – they could (and probably will) nearly double. While that seems catastrophic, it is still less than half of what the 2017 H3N2 outbreak was responsible for. So ignore the breathless headlines and day to day updates: nothing significant has changed. The numbers are converging towards where they have been estimated to go.
All that said, I don’t want to downplay the stress this is going to cause our health care system, and the risk to vulnerable people. As noted in previous posts, this virus hits hard vulnerable populations – especially those over 65 or so and with health problems. Take a place like Chatham County, GA. As I understand it there are 155 ICU beds to serve population of around 400,000. That may not sound like much, but it is slightly above the national average of 33.6 beds per 100,000 people (Chatham is ~38). Typically about two thirds are in use at any given time. The problem is that based on the data we should expect to need a surge of 60 additional ICU beds due to COVID19 for several weeks. I hope the various authorities are planning on this both in Savannah and across the country.
In short, for what it’s worth, my concerns are in order of priority:
1) the economic impacts (extremely high level of concern).
2) the stress on the health care system (somewhat high level of concern).
3) general population impacts (manageable if everybody is sensible).
What does that mean to you? Same thing as yesterday: Wash your hands, don’t touch your face, don’t freak out. The best source of practical information are at the CDC web site, and the DHS/FEMA “ready.gov” pandemic preparation site. Essentially, these are common sense actions. If you or a member of your family is over 65 (and especially over 75), or has health problems (especially respiratory or immune system issues), you should take some extra precautions. Avoid crowds, limit travel where you will be exposed to people, be super-fastidious about hygiene, and so forth, until this thing subsides, hopefully in a few months.
What about quarantines, such as Italy is (unsuccessfully) trying to do in their north? Well, this horse has been out of the barn for a long time. They probably aren’t terribly effective at this stage other than to further screw up the economy and panic people. Quarantines are only effective for small populations you can easily isolate. That day passed for the SARS-COV-2 virus a long time ago. What will work are “mitigation” measures – things like social distancing, emphasis on hygiene, limiting large gatherings, etc. But don’t do this …