COVID-19 cases that began to surge in the USA in June,
peaked in July, and have continued to ease leading to lower hospitalizations
and deaths (see figure below). While infections
continue to erupt in certain parts of the USA, the largest outbreaks in
California, Texas, Florida, Georgia, and Arizona have all topped out leading to
improving trends for the USA as a whole.
The 7-day rolling average of daily cases has fallen from a high near
70,000 in early August to near 40,000 recently.
The US can continue on this virtuous path if the President stops
waffling about masks and tests.
It is far too early to declare victory because part of the decline in newly confirmed cases is due to a significant reduction in testing
(see figure below). The 7-day rolling
average of daily tests peaked 4 weeks ago near 810,000 and has since declined
16% to near 680,000. It is unclear whether
this is being driven by a President that continues to be ambivalent about doing
too
much testing and/or a CDC that
has recently eased its guidance on testing.
Delays
in getting test results continue to plague the country. While the positivity rate has improved from a
high near 9% to 6%, it is still higher than the near 4% low reached in early
June. Moreover, since deaths lag daily
new cases by 3 to 4 weeks, death counts have just recently topped out near
1,100 per day in early August. Due to
the high number of cases in the pipeline, 21,000 more Americans will almost
certainly die over the next 4 weeks
This summer outbreak differs from the spring outbreak in two
very important ways. One is that the
case fatality rate (CFR = deaths/cases) is much lower the second time around as
more testing produced more asymptomatic and mildly symptomatic cases that do
not require hospitalizations. Thus the CFR
for the country as a whole that was 5.2% for cases that resulted in deaths this
past winter and spring (to 6/20/20) improved to 1.7% for deaths reported and
projected for the period 6/20 to 9/22. (Note
that the CFR for an active pandemic will necessarily be only a rough estimate
as many factors that affect the calculation are dynamic.)
|
COVID-19
|
US cases
|
US deaths
|
US CFR
|
FL cases
|
FL deaths
|
FL CFR
|
|
spring/winter
|
2,330,577
|
121,980
|
5.2%
|
93,796
|
3,144
|
3.4%
|
|
summer
|
4,708,878
|
81,407
|
1.7%
|
587,353
|
9,489
|
1.6%
|
But one interesting question that it raises is whether any
of the improvement in CFR is associated with any improvement in techniques or
therapeutics used to treat COVID-19 patients.
Careful clinical studies will be required but the early answer seems to
be no. The US numbers are influenced by
too many different factors but cases in Florida were less disparate and if we
look at the number of hospitalizations compared with deaths it should show how
successfully the hospitals were able to cure their patients. The strong correlation between deaths and
hospitalizations in FL is there even after we smooth out the strong weekly
reporting cycle by comparing 7-day rolling averages. The slope of the best fit straight line
indicates that 32% of those going to hospitals for COVID-19 end up dying with
the summer showing worse above-trend behavior.
(The percentage may be lower due to those who die outside of hospitals.) We expect that wider availability of
Remdesivir, steroids (dexamethasone),
convalescent plasma and improved technique may eventually drive this number
down. Until then, vulnerable adults are
still well-advised to avoid getting infected and hospitalized.
The other important difference is that so far the summer
outbreak has avoided general lockdowns that were imposed by scores of countries
and 43 US states in the spring and that came with enormous economic and social costs. As a result of the resurgence, certain states
have rolled back some of their more aggressive reopening steps taken in May by restricting
select businesses such as bars, indoor dining, gyms, theatres, and other
crowded venues. Some states and numerous
cities and counties have mandated mask-wearing in public and closed spaces.
In early August when few of these measures were working, some observers
such as Osterholm
and Kashkari and the NY
Times Editorial Board called for a general lockdown to crush the
pandemic. Many observers now suggest
that selective business closures combined with masking, social distancing, and diligent
personal hygiene can help to flatten the curve without general lockdowns. These cost-effective steps have been widely
recommended by health organizations such as the WHO and CDC, and business
organizations such as the German Institute
of Labor Economics and Goldman
Sachs Group. Along with more accurate
and timely testing, contact tracing, and selective quarantines, this low-cost
approach might convince more businesses, institutions, and individuals that it
is possible to reopen the economy safely.
However, this approach does require that the President stop his waffling and
mandate mask-wearing and push for accurate and timely testing. These should have never been politicized in
the first place.
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