Coronavirus

COVID-19 cases in the USA have shown a sharp decrease over the last 8 days causing the 7-day rolling average to peak and rollover (see figure below – red squares).   The question is whether this is measuring a real lasting phenomenon – perhaps attributable to local COVID-19 fires burning out, or to mitigation factors taking hold, or to some temporary factor associated with the Thanksgiving holiday.   The answer is probably a combination of all three that will ultimately be overwhelmed by an increase in Thanksgiving transmission. Some COVID-19 outbreaks have burned so strongly and for so long (3-4 months) that local “herd immunity” may be acting as a retardant to the fire.   For example, in North Dakota (ND) 10.3% of the population has now been confirmed infected (see table below).   State Confirmed Testing Est. Pop Deaths Death per Fatality   Infection % Positive % Infection %

Amidst the bad news of COVID-19 increasing in the USA for the third time to record levels, there is some evidence that the case fatality rate (CFR = deaths/cases) has improved significantly from spring to summer.  Two large studies of patients in NYC and in England both show significant improvement in survival rates.  We have done a study of cases in Florida and find a similar trend in improvement.  The figure above shows that cases (brown squares) in Florida first increased in March and then eased in June, only to surge again and burn out by early October.   Since then cases have risen again for the third time and deaths (blue diamonds) appear to have bottomed out and are increasing again.   During the first wave, the first 82,719 cases reported in FL on 6/17/20 were responsible for most of the 3702 cumulative deaths reported on 7/4/20.   This corresponded to an overall CFR of 4.5% (with deaths lagging cases by 2-3 weeks.   The second wave ended roughly on 10/20/20 with 676k more ca

The total number of COVID-19 cases in the USA surpassed ten million or 3% of the population today.   The third wave of the Pandemic in the USA is here and it looks extremely dangerous.   For the first time, the number of confirmed cases per week has reached 700,000 or more than 100,000 per day – 50% higher than the peak of the summer wave reached in July (see brown squares in the figure below).   Cases are rising everywhere this time around in contrast to the first wave which was concentrated in the Northeast and the second wave that was concentrated in the Sunbelt.   This third wave differs significantly from the first and modestly from the second in other ways.   Testing now is much more thorough than the first wave and slightly better than the second wave thus identifying more asymptomatic and mildly symptomatic cases than before (see figure below).   More kids and young adults are being tested now increasing the percentage of silent carriers.    But the new cases are not all benig

COVID-19 cases are increasing around the world, in the USA, and in Florida.   In Florida, cases have been rising for the last 5 weeks albeit at a slower rate than many northern states as temperatures have cooled and activities have moved indoors slowly in the Sunshine State.   In Florida, the push to reopen the economy and especially schools have exacerbated the problem.   Since schools have reopened in August it is clear that kids can get infected and high school kids are as likely to get infected as the general population (see graph below).   College kids and young adults are nearly twice as likely to get infected since they are more mobile and are less risk-averse in general.   While younger kids appear to be less contagious than older kids, their infection rates have been going up with the general population and for kids of elementary school age (5 - 10) it is now about 45% that of the average population.   Even though kids (<18 yrs old) are unlikely to die from COVID-19 (in f