How many tent revivals does it take to alter the trajectory of an epidemic?
When Kentuckians did the hard things necessary as we entered the great unknown of a new viral disease, we altered the course of the Covid-19 pandemic in our Commonwealth. If we had remained on the initial exponential curve we were experiencing, the entire state would have been infected in a matter of weeks. We have met and passed that challenge– for now. Governor Beshear, Public Health Commissioner Stack, I, and all the rest of the hopeful Kentuckians would like to have believed that the number of new cases would steady, if not decrease altogether. Looking at the reported data and given what I understand to be the definitions of the individual data elements, I believe that the number of new cases is on the rise again. Saturday’s new cases numbered 310, the highest since May 5 when an institutional outbreak was recognized and reported all at once. Indeed the 7-Day rolling average of new cases daily has never been higher than it is now. Reported deaths or hospitalizations have not been rising substantially, but those numbers take longer to show up in reports. Other states are also reporting upticks in their case counts as society opens up.
Are rising cases the simple result of more testing?
The reporting of tests done daily remains erratic. Even though “Tests” now include both viral RNA and patient antibodies, the 7-Day average of Kentucky tests reported daily has actually been decreasing since the first of June. (See below.) The Basic Reproductive Rate (the average number of people that a given case will infect in turn) has been rising. The percent of daily tests that are positive has not changed much. Based on publicly available numbers, I cannot agree yet that the increase in cases is explainable by more testing.
What is happening around us?
What I can confirm is that our collective behavior has changed dramatically as epidemiologic measures have been formally relaxed to “open up the economy.” I noticed major behavioral changes the very first day that retail stores were allowed to open– albeit with limits. As I drove out of town to ride my bicycle in a rural setting there were clearly more cars on the road in general. The traffic on Shelbyville Road near the shopping centers was back to stop-and-go through the lights. The parking lots of the big malls went from nearly empty to what may have been a third full when seen from the road. The restaurants in St. Matthews were peopled again as were the sidewalks of Frankfort Avenue. Groups of individuals both young and older were about without masks.
Surely a collective sigh of relief became manifest as we were given permission to leave our homes more freely. I cannot blame folks. Neither can I argue that the time for gradual changes had not yet arrived. We paid a heavy price to retard the spread of a new infectious agent that had already shown its dangerous spots. We did this to prevent our healthcare system from becoming swamped, to decrease deaths if possible, to allow time to learn more about this new plague, and to develop effective treatments and a vaccine. I’d say that the plan has been working as hoped. I will also say that we are far from having stopped this virus in its tracks. We need to do more than just flatten the curve. To decrease the total number of deaths for the foreseeable future, we need to decrease the area under the curves which is the measure of total eventual deaths. Is it all right to move away from ground-zero confinement? Surely. But we must do so wisely.
How about them unwise behaviors?
Last week, the Lexington Herald-Leader reported the consequences of an “Old Time Gospel” service held in Jessamine County. That May-5 report noted that there were at least 17 attendees (from under the tent?) who contracted Covid-19 disease. It would appear that the of outbreak revealed itself because people were getting sick, not because of testing. Many of the congregation were asymptomatic, including many who lived in adjacent Fayette County– home of the second largest city in Kentucky. The course of this Holy unnecessary outbreak remains to be seen, but church-sponsored outbreaks have been a source of major disease-flairs in Western Kentucky and elsewhere in the world.
To what degree should churches or other self-designated religious organizations be given a green light to ignore the practices to which others are bound by recommendation or regulation to follow? This is going to be a tough issue to deal with, especially given that Kentucky’s Attorney General Daniel Cameron is giving a go-ahead to gather together. From the perspective of a healthcare professional, I can only interpret the Attorney General’s actions in this matter to be politically motivated rather than to protect the health and well-being of Kentuckians. (It is ironic that the pastor of this fundamentalist church joined with Attorney General Cameron threatening to sue Governor Beshear to allow church services. It looks like they got what they didn’t pray for!) Would a performance of a traditional clown and elephant circus under a big tent have been permitted? Under what circumstances can a law applied to the general public be applied differently to others? Some people who had never heard of the church above are going to get sick. Some may die. Another “huge tent revival” was still on the Nicholasville church’s book as of last week. I see troubles ahead, both medically and politically. Church services may be a lesser problem when compared to getting people to cooperate with contact tracing or renewed quarantines.
Is there an additional way to detect outbreaks?
If we had a well-coordinated healthcare system that could collect information about sick people and report it in a timely manner, we could begin to take action even before the swabs were swabbed, the tests performed and reported, or our clinics and hospitals were filling up new sick people. Unfortunately, we are not there yet. Readers of these pages know of my concern that the current status of our national public health system is not performing as we expected. Some would go so far to say the CDC has failed us or has been ignored. The data that is available to me and to nation’s aggregators of Covid-19 epidemiological data– such as Johns Hopkins, the New York Times, or the Covid-19 Tracking Project– is full of missing data, is non-uniformly reported by states, uses different definitions or standards, has built-in delays, can be changed after the fact, and is subject to political pressures.
What does it say about our national healthcare and public health systems that I cannot look to the CDC for reliable information– or for that matter any of the tables of numerical information that I expected? I have been updating Kentucky’s numbers daily as new evening reports are given by Governor Beshear. There is much about the structure of the reporting that I do not fully understand. The national aggregators are in the same boat. I have asked the Governor’s Office and Cabinet several times by both email and phone for help and for a cumulative official tally of the major numbers reported but have not received a response. I assume those folks are too busy and I reluctantly give them a pass. However, I must therefore make assumptions about our home-grown data that may not be fully correct. Below are a few observations in support of my concern that we are not as well prepared to use publically available data to identify scattered outbreaks in a sufficiently timely manner to do anything definitive about them.
Data reporting is erratic, sometimes absent, and occasionally erroneous.
Look at any reported media summary of new national cases and tests and you will see curves and bar charts jumping up and down in large daily swings that fall often to zero one day and rise dramatically the next. The reason for this is that it depends on what day of the week it is! For example, below is a bar chart of Kentucky’s New Testing data as reported to the CDC. (Data from Covid-19 Tracking Project.) Note the negative adjustments on two days in May.
The aggregate number of reported new tests has been highest on Tuesdays and Fridays, and lowest on Sundays and Mondays. (New tests are defined in this data visualization as the increase in tests from the day before.) Note that on days following those when no cases were reported that there are corresponding increases over the next day or two. Changes in testing and/or reporting over the weekends obviously have a major effect on what each day’s numbers look like and distort any derivative calculated result. In practice, the significance of a big jump in data either way cannot be interpreted by itself. The weekly ebb and flow of reporting is the reason why we now commonly see 7-day averages used to determine the overall direction of change. I have moved to this practice as well. Looking at changes in aggregate total counts was useful in the beginning when counts were relatively low but that viewpoint is no longer sensitive enough to visually detect even moderate changes.
Below are two figures derived from data accumulated daily by KHPI from Governor Beshear’s end-of-day presentations.
It is a truism that as more tests are done, more positives will be found. The percent of tests that are positive will depend on the illness status of individuals and the prevalence of disease in communities being tested. In a perfect clinical world, we would also collect data from people with symptoms that are compatible with Covid-19 even before testing results are available. It is my understanding that our clinicians are proceeding in this way already. I want to believe that our public health departments already have the necessary reporting structure and resources of both funding and personnell to collect such clinical information throughout the state. Otherwise we will be playing whack-a-mole for some time to come and we all know how difficult that is!
An interactive data visualization of these graphs and others are available on KHPI’s Tableau Public Website.
Peter Hasselbacher, MD
Emeritus Professor of Medicine, UofL
June 8, 2020