What the coronavirus numbers are telling us
There are lots of numbers flying around about the coronavirus, so here is a brief attempt to put some context to them.
The United States daily new case volume rose to the mid 30,000 range in April, then started a slide to about half that level in mid-May. Since then, there has been a steep rise, to the mid 70,0000 level last week, down a bit this weekend to the low 60,000 level. The distribution of cases among the states has also changed. In the first surge, New York, New Jersey, Connecticut, Massachusetts, Illinois, Michigan, Pennsylvania, and Louisiana were hardest hit. In the last 6-7 weeks, Florida, California, Texas, Arizona, Georgia, South Carolina, and a few other states in the southeast have had the highest volumes, though a large number of states have rising numbers.
The fear surrounding the virus is, of course, most associated with its death toll. The daily number of new deaths reported is far lower now, even with the much higher daily new case levels, than at the peak of daily deaths two to three months ago. Daily deaths were regularly in the 2,000 range or higher, reaching 2,500 per day, and dropped to the 500-750 per day range in June. They are up a bit now to close to 1,000 on some days, with higher death tolls in the most severely hit states, likely to increase more since there is a lag between positive testing results and deaths associated with the new cases.
This country has the highest caseload in the world, and one of the highest caseloads in the world compared to population. But as far as deaths, many countries have higher death rates per million people than we do. In addition, there is the case fatality rate: deaths divided by positive cases. The US case fatality rate has dropped steadily for several months, from about 6% to below 4%. Death numbers are lagged, as indicated already, but back in April, new deaths were on some days 6-10% of new positive cases. The last few weeks, that percentage has been about 1-2%. The US case fatality rate is far lower than many other countries, including our developed world peers in Europe.
Why have the case volumes grown? There are probably many reasons for this. Some states reopened their economies earlier than others, and have had sizable case increases. Some of the higher volume has come from much higher levels of testing (nationally now over 700,000 tests per day), but positivity rates are also growing in many states, suggesting community spread. There are probably large numbers of asymptomatic cases in the population, some of which are showing up due to increased testing. Only sick people were tested early on.
As many as 15-25 million people were on the streets demonstrating after the George Floyd killing, according to New York Times estimates. Some wore masks, but social distancing did not occur. Many criticized President Trump for holding an indoor rally in Tulsa, which may have drawn 6,000 people. The numbers since the rally do not suggest any surge in fatalities in the city since the rally, though case volume is up some.
The critics of the Tulsa rally have been shy about any possible link between millions of demonstrators on the streets in tight quarters, and much higher case volumes in dozens of states. Some political events that add to risk of virus spread are clearly more worthy than others. There is also the possibility that warmer temperatures are driving people indoors where air conditioning is recirculating the virus and spreading it among people.
The EU has a larger total population than the United States and has had more deaths from the virus than the United States. But its daily volume of new cases is less than 10% of the US new caseload recently. This suggests that widespread transmission is not occurring in Europe (Russia is a different story), while we have not tamed the beast. Deaths are a different story: case fatality rates in many Western European countries were well over 10% (our current rate is 3.8%).
Anthony Fauci last weekend stated that New York State is the model for how to handle things in this country. I do not think this was a very thoughtful comment. If you consider each American state as a country, the two highest death rates in the world -- deaths per million people -- would be New Jersey, and then New York. New York had 32,000 deaths in a state with 19 million people. Its death rate per million is more than 4 times that of the rest of the country without New York. Its case fatality rate is double that of the rest of the United States.
It would be hard not to conclude that there were many thousands of excess deaths in New York. Why did this happen? Even setting aside the decision to put Covid positive patients into nursing homes, the death toll in hospitals was much higher than anywhere else in America other than New Jersey. These states were hit hard and early and had no real models of what to do with very sick patients. Other states are doing better; less use of ventilators, different positioning of patients (keeping them upright), more options for treatment, and earlier identification and treatment of sick patients. The mix of patients today is also younger than early on, and this also contributes to a lower fatality rate.
New York’s new daily case volume is down to a bit less than a 1,000 a day, less than 10% of the peak in April with a positivity rate of 1% among test takers. That is good, but to applaud that and disregard the ghastly death toll in the state is simply wrong. Illinois’s case volumes have started moving up a bit, but there is lots of testing going on, and the positivity rate is only 3%, also quite low. Mayor Lightfoot is already pulling back on re-openings. She would, I am sure, prefer to deal exclusively with the virus, and ignore the out of control gang violence in the city, which could produce a record number of homicides and shootings this year.
One other data point: at the peak in April, approximately 60,000 hospital beds were in use nationally for Covid patients. That dropped sharply the next 45 days, and is now rising and is close to the 60,000 level again. Nationally, there are about 1 million hospital beds, and 100,000 ICU beds. At the peak ICU beds were needed for a third or so of hospitalized Covid patients, higher in some New York hospitals That fraction (ICU beds to total covid patient beds) is lower so far in the current wave, which may relate to the age mix of hospitalized patients, younger than In April.
As to how to reduce the case volume, which will aid school re-openings, and the economy, I do not have much to add to the general advice on mask wearing, social distancing and good personal hygiene. There is generally positive news on new treatments and vaccine efforts, which would be much bigger bullets to fight this going forward.
Death rates among the countries (per hundred thousand-multiply death rate by ten to compare to state death rates)