This week we revisit the mystery of the falling mortality count, even as the infection rate continues to rise alarmingly in the US. We find some signals in the data that helps explain this paradox, and which indicate that we face some serious problems.
The Mortality Rate
The secular decline in mortality from COVID-19 continued in the US over the past week. There is, in this metric, no detectable signal of an uptick from the dramatic increase in the infection count concentrated the southern and western states that is being widely reported in the press. The mortality rates in those states should have climbed significantly by now, and should be impacting the US wide figures. The graph show however an unbroken and consistent decline, week-by-week, of deaths in the US. The one week trailing average line is declining at a consistent and steady rate.
In March we wrote “…the most reliable statistic is the mortality rate…New case numbers, the ones most frequently quoted in news reports are not only unreliable, but have proven to be materially incorrect.”
We considered last week whether the widespread testing may itself be a contributing factor to the reported level of infections. We published a new chart, showing the rise in infections correlate quite closely to the rise in the testing rate, while the mortality rate continues to decline. Here is an update to that chart.
We have researched this theory and have found several possible reasons why this correlation may not be the reason for the report on increase infections, and that this increase may be real.
The “Pneumonia” Theory
First, we should dispose of one theory that we were alerted to on social media. The claim was that the actual rise in COVID-19 deaths was being hidden in deaths categorized as “pneumonia”. This theory arises due to a misreading of the CDC data, as many COVID-19 deaths occur when there is also a Pneumonia diagnosis. The guidelines require pneumonia deaths, when accompanied by other COVID-19 symptoms to be reported as COVID-19 deaths, regardless of the primary cause of death. This can easily be seen in the total mortality counts, and in the CDC reports of “Excess Deaths” – i.e. the total numbers of deaths in excess of that which is statistically expected. In each case, the CDC adjusts these numbers to compensate for late reporting, and continuously corrects the totals once all reporting is complete. The CDC Excess Death report shows clearly the declining Excess Death rate.
The second set of reports groups death by select causes of death. Covid-19 related deaths may be included in several of these categories that show significant excess death rates for the period. The important issue is that in all cases, the death rate has returned to the levels of 2015-2019.
The Key States
We are tracking California, Texas and Florida as the key states experiencing a very substantial rise in infections, while at the same time representing a very large fraction of the US population. A brief summary of the historic record for these three states show a recent strong rise in infections, and – just as we observed for the whole US – no apparent rise in the mortality rate.
As we have said repeatedly, there is no clear signal in these numbers. However, the graph is based upon the number of days established in the literature – twelve – between infection and death. What if this is not correct, and the average time between infection and death is longer – say three, or even four weeks? This would mean that we would only begin to see the mortality rate increase in the upcoming weeks, meaning the worst is yet to come. There are some indications that this may be the case.
Using the IHME (Institute for Health Metrics and Evaluation, University of Washington) numbers, we have summarized the hospitalization statistics for California, Texas and Florida as follows:
These numbers show that after falling to a low at the beginning of June, hospitalizations began to increase, reaching up to 30% increases by today. These numbers are serious, and indicate that the growing number of infections are accompanied by a growing number of people contracting the illness.
Of greater concern is the numbers that the IHME project for the end of August. This shows a combined number of beds required rising to almost nine thousand by the end of August, and this is despite their projection that California will have declined from its high point in early July. This will place a very significant strain on the healthcare resources of both Texas and Florida.
Opportunities for Action
Actions need to be taken, as the evidence is now clearer that the rise of infections in the southern and western states do mean an increase in COVID-19 cases. It may be that these cases are amongst younger, and healthier people than occurred previously, and this may result in a lower – and perhaps briefly deferred – death toll. However the healthcare resource use is very significant and could once again strain the system.
We have tried to hammer home the appalling state of testing in the US. It still is seriously lacking for want of a national emergency program to force the states and localities to implement a comprehensive program.
The current testing regime has not been able to provide the metrics to properly measure and track the pandemic, and we remain in the dark as to the scope of the disease. Johns Hopkins publishes a test tracker, and the image below is a high level view of this tracker showing the state of testing in our nation.
It is easy to understand: states in red are testing far too little, while those in yellow are at optimal level, with varying degrees of orange in between. It is no accident that the problem states are those in bright red to light orange. The colors denote the fraction of those tested that are NOT positive. In other words, it isn’t helpful to control the disease if you are only testing those that are already ill. By testing a wider sample, you are able to track the extent of the spread, and so control it.
The lessons from those countries that have controlled COVID-19 is simple: without the enforcement of an effective testing regime, it is not possible to overcome the pandemic.
This diagram also shows the flaw in the theory that the additional testing was the cause of the discovery of the increase in infections: the states that have shown the greatest increase are those that focus only on testing those with symptoms. So testing is not the reason for the discovery of a large number of cases in those states.
2. Masks and Social Distancing
Masks and social distancing has been demonstrated to effectively reduce infection rates. Despite this, many members of the public, as well as – quite surprisingly – public figures have opposed this. It is difficult to understand the reason for this. We suspect some of it is a combination of various cause: laziness, ignorance, a sense of youthful immunity, and – most inexplicably – political opposition. It seems that a strong, active campaign to encourage these practices is both necessary and urgent.
The way forward
Failure to implement effective, widespread testing of those that are not yet showing symptoms, and using the the simple, but effective controls of masking and social distancing will cause the US severe human, social and economic damage.
Implementing these policies requires leadership, and leadership at every level of the political, social and economic spectrum. If those at the top don’t act, that does not excuse any of us from setting aside our political differences and focusing on implementing solutions rather than pointing at (and sometimes taking delight in) the failures of others in formulating and enforcing policy. There is far too much to lose.