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-19US casesUS deathsUS CFRFL cases FL deathsFL CFR

 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.