October 14, 2020 - The Perils of Inadequate Testing
The Perils of Inadequate Testing
October 14, 2020
In the West, Midwest and certain pockets of the South, the second wave of coronavirus infection is characterized by rising cases and hospitalizations. The current status of infection in Alabama is less clear. As of today, there are 834 statewide patients in 108 reporting hospitals, an increase of 13 patients from yesterday, when 106 hospitals reported. Less than 3 weeks ago (9/25), there were 703 patients in 100 reporting hospitals. Hospitalizations are certainly on the rise but the rate of increase is not yet alarming.
Evaluating the pattern of daily cases is more difficult in Alabama due to inadequate testing. In fact, I believe limited testing in our state is the single biggest obstacle for determining whether a second wave is imminent. Lack of testing, or testing only the most symptomatic persons, will inhibit the ability to identify trends and to respond effectively. Today’s Alabama data illustrate this point.
ADPH reported 784 new cases today (incl 122 probables) but only 5,014 tests. That means we had a one-day positivity rate of 15.6%, which caused our 7-day rolling average to rise to 14.1%. If you focus only on the daily cases, you might conclude that Alabama is doing okay because we had fewer cases than our 7-day rolling average of 937. But then, imagine if Alabama did as much testing as our neighbor to the north - Tennessee.
In the last 7 days, TN averaged 2,787 tests per 100K population, while Alabama averaged just 994 tests per 100K. Meanwhile, TN averaged 171 cases per 100K population, while we averaged 135 per 100K. If we had tested at the same rate as TN over the last 7 days, our case count might well be 379 per 100K population - which is equivalent to an average of 1,854 cases per day. That would definitely qualify as a second wave that is as bad or worse than the outbreak we experienced in July.
If you ever doubted that adequate testing is a critically important factor in gaining control over this virus, consider the following. There are 7 states with a 7-day rolling average positivity rate under 2%, all of which are located in the Northeast. Here they are, followed by their national ranking in per capita testing over the last 7 days: ME (0.48% - 9th); VT (0.91% - 39th); MA(1.01% - 2nd); NY (1.17% - 6th); (N.H. 1.42% - 11th); CT (1.48% - 5th); and RI (1.76% - 1st). In other words, 6 of the 7 states with the lowest infection rates in the country are among the top 11 states in per capita testing. Vermont is the only outlier.
Now, compare this list to the states with the highest positivity rates - i.e the only 8 states above 15% positivity rates. Here they are, followed by their national ranking in per capita testing over the last 7 days: SD (23.58% - 26th); ID (23.49% - 42nd); WI (21.11% - 34th); IA (18.82% - 41st); WY (16.67% - 39th); KS (16.64% - 43rd); NV (15.71% - 48th); IN (15.56% - 41st). In other words, 6 of the 8 worst states are among the bottom 11 states in per capita testing.
Where does Alabama stand? Over the last 7 days, our state ranks 45th in the nation in per capita testing and has the 10th highest positivity rate. We even may be on the brink of a second wave of infection for which we are unprepared because of inadequate testing. The totals:
10/1 - 1,043
10/2 - 954
10/3 - 1682
10/4 - 789
10/5 - 544
10/6 - 764
10/7 - 941
10/8 - 557
10/9 - 1490
10/10- 1061
10/11 - 816
10/12 - 734
10/13 - 1117
10/14 - 784
The number of counties with positivity rates above 20% continues to grow, reaching 19 of the State’s 67 counties today, as compared to 17 yesterday.