Currently we’re seeing new states entering the exponential phase of confirmed cases and deaths. As I’ve mentioned recently, I don’t trust the confirmed case statistics much, but they’re interesting as a curiosity. There’s a very wide range of approaches to testing and classification of an individual as a “confirmed case.” For instance, we have Iceland who has a randomized testing strategy that is resulting in large numbers of asymptomatic confirmed cases. On the other extreme we have Iran and China, where reports indicate all confirmed cases were symptomatic and largely hospitalized. So in China’s Hubei province, the 4.7% death rate was calculated largely on a base of cases made of of largely very sick people. If one assumes that Hubei’s 68K confirmed cases was just 40% of the total infected population, the death rate drops to 1.9%. (See HERE for report on how Iceland is finding out that 50% of total cases are asymptomatic). There’s a very big difference depending on how one measures. In the chart above, we’re measuring the number of confirmed cases per 1000 residents (the color of the bubble) along with the instantaneous slope of the curve of deaths per 1000 residents over time. You can see on the map that if the rate of deaths isn’t severe, you can barely see the dot on the map. This way, if you can see it, it’s a region that is really being impacted by COVID-19. Recently there has been a lot of activity in Chicago, Detroit, and New Orleans along with the large numbers of cases and deaths in the NY/NJ region.
The Latitude Effect Still Holds
I have noted a few times that it is strange how the severity of the outbreaks is focused more on certain latitudes. I suspect that much of this has to do with the temperatures at these latitudes during February and March, but it’s possible that there are other reasons too. You can see in the chart above, that when normalized for population, latitudes 40-50 North and 50-60 North have most of the world’s cases. The strange thing to me is that Latitudes 40-50 North has consistently had double or more the number of deaths per 1000 people. This trend continues to hold, as does the trend of few cases between 0 and 20 degrees North (too hot there, likely) and 60 to 70 degrees North (too cold?). See the table below for the actual numbers.
Will the latitude effect hold up? As temperatures in the northern latitudes increase during April, will their rates of new cases and deaths slow? No one knows right now, but I think I have built analytics tools that will detect these trends quickly.