COVID-19 fatality rate continues to drop in Florida


This is an update of the information in our July 10July 15July 24 , July 30August 10, August 17 , and August 25 articles on this topic. The graph above shows that even with the deaths through September 7 added to the data, the death rate for people who tested positive for COVID in June, July, or August was much lower than it was in April.

There was a great deal of concern about rising numbers of COVID-19 cases in Florida in June and July, but the real question is whether these cases have translated into correspondingly large numbers of deaths; as we’ll show below, this is unlikely because people who get sick now are far less likely to suffer adverse consequences than they were in April or May.

Similarly, there is now concern about large numbers of college students testing positive.

We used Florida’s case line data (September 7 update), which does not exaggerate the number of cases because it includes one line per person. It also shows whether or not that person was hospitalized or passed away (but not the date of either). Using this data allows a comparison of cases to deaths without worrying about a specific lag time for the disease process. The graphs include the entire state instead of Alachua County because the county didn’t have enough COVID-19 deaths over that period to make the data meaningful.

The graphs below show the percentage of daily cases that later died, regardless of death date (i.e., the graph shows the percentage of people who tested positive on each date who later died). The overall rate has dropped dramatically since the start of May. The 65+ rate has been dropping since mid-April and started dropping even faster after May 27. Note that these graphs stop with people whose case dates were August 17, allowing 20 days for the cases to resolve. (We’ve found it takes about 20 days for most of the deaths on a given day to be reported.)

This table shows how the overall average COVID-19 death rate for Florida residents has dropped by 68% from April to June and 74% from April to July; the death rate for those over 65 has dropped by 38% from April to June and 51% from April to July.

Note that these are case fatality rates; various studies have shown that a large number of cases are never detected, leading to an infection fatality rate that is on the order of 1/10 the case fatality rate.

Aug (1-15)1.19%6.48%0.20%

The following graphs show how the case fatality rate has changed since the beginning of April for all cases, for people over 65, and for people under 65.

Below is a graph of the case fatality rate by age in Florida and Alachua County, followed by the same graph broken out by month (Florida only) to demonstrate the decreasing fatality rate.

This is where we can see the extremely low risk to college students. The overall case fatality rate for the 15-24 age group is .03% (3 of 10,000 cases). For the 18-23 age group, there have been 21 deaths out of 71,352 cases. It was difficult for young people to even get tested before June and young people are more likely to have mild illness, so the proportion of missed cases in this age group is at least as high as the number missed overall. Using the 1/10 factor leads to about 3 deaths in 100,000 college-aged students who become infected with COVID. While every one of these 21 deaths was a tragedy, many of them were reported to have pre-existing major health issues. The fatality rate for healthy young people is close to zero.

If we remove residents of long-term care facilities, the case fatality rate for Florida residents 65 and over is much lower. Unfortunately, the Florida Department of Health has not updated their age-stratified long-term care facility death data since July 24.