COVID-19 Growth Rate Trends

The number of confirmed COVID-19 cases has increased by this much daily (most recent three days average) in the following countries:

1) Korea: 1%
2) Japan: 5%
3) Italy: 14.2%
4) Spain: 22.8%
5) Germany: 26.8%
6) USA: 29.6%

Korea
Korea seems to be getting close to getting the epidemic under control. Patients who have officially recovered now outnumber new infections day by day. That is very encouraging.

Japan
Due to geographic proximity and economic relations with China, Japan was also one of the countries with early cases, many of them visitors to China. It crossed the 100 confirmed case threshold on February 22, one day before Italy, yet the outcome could not have been more different. Since then the case number doubled three times in Japan (about every 8 days on average) versus 8 times in Italy (about every 3 days). Confirmed case numbers can not always be taken at face value as they can be quite dependent on the amount of testing and most mild cases will most likely never be counted. There could easily be an order of magnitude more cases than listed in the official statistics. However, 28 deaths in Japan vs 2,503 in Italy (i.e. about 90 times more) suggests that there were actually hugely different outcomes in these two countries. Japanese infection case numbers have increased about 9 times since they were below 100 whereas in Italy they increased about 400-fold since that threshold. One would expect higher mortality in Italy once the medical system was stressed to limit and beyond. Quite plausibly Japan and Italy have been counting a similar percentage of actual cases, but case numbers have been growing much slower in Japan (9% daily average over 24 days) than in Italy (28% daily average over 23 days) and with less stress to the medical system, outcomes have been less lethal on top of numbers being smaller. With intensifying efforts at social distancing, Japan may be next at halting the spread for now. It will still be a difficult road.

Italy and Spain
In Italy the absolute number of daily new infections has been more or less flat for the last 4 days. As a percentage of existing cases it is now half of what it was about week ago, but as total numbers still tripled, the new cases are still at a peak, even if steady. In Spain too the daily increase as a percentage has slowed but like in Italy it has some way to go before it comes close to zero.

Germany and US
Neither in Germany nor in the US is there a clear drop in the daily case growth percentage yet. They are still in exponential growth. Hopefully self-isolation measures will bite soon.

Other numbers
Germany has 5 times as many respirators as France (25,000 vs 5,000).

Italy now has about half as many infections per million inhabitants (~500) than Hubei province, where Wuhan is located, had at the peak of the local outbreak (1,100 per million).

Sources:

COVID-19 Growth Rate in USA and Italy

“And again, when you have 15 people, and the 15 within a couple of days is going to be down to close to zero, that’s a pretty good job we’ve done.”
(Donald Trump, Feb 26, 2020)

Looking at charts for the number of total COVID-19 cases in the US and in Italy, it looks like in the 11 days from March 1 to March 12, case numbers increased by an average of 33% per day in the US (75 to 1697).

A week earlier (February 22) Italy already had a similar number of cases and numbers have also been growing exponentially (79 to 1701 in 8 days, an average daily increase of 48%). The infection growth rate seems to have slowed to around 24% after quarantine in parts of Northern Italy and then a countrywide lock down on March 9 (1701 to 15113 cases in 11 days). Nevertheless, in some of the worst affected areas in Italy the health care system is already stressed to the breaking point.

Assuming the US case numbers keep increasing at 33% a day, it would exceed a million cases around April 4. At 24% it will happen a week later, on April 11. But regardless of the timing, if 5% of a million infected Americans were to need intensive care, that’s more than there are ICU beds in the entire US (and most of those are already in use, of course).

This is a very worrying picture. Obesity, high blood pressure and diabetes are known risk factors for severe outcomes of COVID-19 and these are highly common in the US. 45% of the US population over 45 are either obese or severely obese (both men and women). On top of that, some 25 million people in the US are not covered by any health insurance.

Worldometers Coronavirus data:
USA Coronavirus
Italy Coronavirus