Coronavirus

Alabama’s COVID-19 Cases, Deaths Trending Downward, Though Data-Collection Concerns Remain

The official COVID-19 data reported by the Alabama Department of Public Health continues to show improvement in most categories, though some questions remain about whether state totals are sometimes incorrect because of reporting issues.

In BirminghamWatch’s weekly analysis of data reported by the Alabama Department of Public Health, the 7-day moving average of new COVID-19 cases for the period ending Wednesday was 622.86 per day. That average has fallen by two-thirds since its high July 19, but in recent weeks it has spiked in both directions because of issues in reporting of positive cases by various testing organizations. The ADPH said last week that some counties had reported higher numbers than normal because they were adding cases backlogged from earlier weeks, and some labs that use the newer antigen tests had not been reporting.

Over the past two weeks, the ADPH website has reported daily new cases as high as 1,561, on Aug. 29, followed by a low of 86 just four days later. For that reason, BirminghamWatch did not publish a weekly analysis on Sept. 2, because the accuracy of data reported in the previous week could not be verified. BirminghamWatch continues to try to determine whether any previous data is affected by these issues.

Alabama Assistant State Health Officer Dr. Karen Landers told BirminghamWatch on Wednesday that some of these spikes occur when new testing laboratories are brought online to report data. “Every time that a laboratory becomes a new facility to us and they give us historic files, they dump some data in and we see kind of a false increase,” Landers said. “But also, if a laboratory inadvertently marks some negatives as positive or vice versa, we get blamed for that — and really we’re just the messenger. It’s an ongoing problem … . We’re at the mercy of all these data sets coming in.”

The longer-term 14-day average is at 746.71, down by 70 from last week. The percentage increase in the number of new positives was up by an average of 0.52% per day over the past seven days, another new low since the figure was first calculated at the end of March. That was down from 0.75% last week.

On the other hand, Alabama has seen an increase in the number of cases that are classified as probable, as opposed to confirmed. Landers said that cases classified as probable are primarily those detected through the use of the newer antigen testing procedure, whereas confirmed cases use the standard PCR procedure.

“This mainly is a terminology issue, from our standpoint,” Landers said. “A case which is a confirmed case is treated the same as a probable case in terms of investigative procedure, in terms of context … . A lot of states don’t differentiate between confirmed and probable. We do in Alabama.”

Landers said the ADPH is looking at including both confirmed and probable case numbers in its own moving average calculations.

The total of positive cases statewide stood at 122,580 on Wednesday, an increase of 4,360 cases over seven days. Another 11,837 cases were listed by ADPH as probable, for a total of 134,417 positives overall. The doubling rate of confirmed cases is now up to a high of 133 days, which means it will take more than four months for the total to double again at this rate.

The 7-day average positivity rate now stands at 13.48%, about the same as a week prior but a jump from the 9.56% level on Aug. 26. As in the past, the increased positivity rate may be tied to a sharp decline in the testing rate. The 7-day average of tests stood at 4,261, falling from 7,433 the week before. The positivity rate is the percentage of positive results from all tests in a period, so a drop in tests administered often will drive up the positivity rate. The ideal rate is considered to be 5% or less.

The state death toll on Wednesday was 2,161, up by 47 over the week, with an additional 124 deaths listed as probable. That gives the state an overall total of 2,285. The 7-day moving average of new death reports fell to 6.71 per day, the lowest since June 17. The daily count of deaths was in double digits only once during the week, and only two deaths were reported from Sunday through Tuesday. The 14-day average is now 14.00 new deaths per day, on a very slight downtrend.