Tourists wearing protective masks walk on Republique square in Paris...

Tourists wearing protective masks walk on Republique square in Paris on Thursday. France prepared to shut down again for a month to try to put the brakes on the fast-moving coronavirus. Credit: AP/Lewis Joly

The coronavirus pandemic hasn't finished with us yet. A spike in infections in recent weeks has sent new cases to records in a number of places around the world including the U.S., which already weathered two waves of outbreaks this year. And the weather is only starting to turn cold.

Europeans have started taking draconian action again, despite the potential drag on their economies. France has introduced a new lockdown which is only slightly less harsh than the one it imposed in the spring. Germany has opted for lockdown-lite. So what is the U.S. going to do?

Hospitalizations, which had been on the decline, are now rising again, with some health systems feeling the strain. In Wisconsin, a field hospital was opened on the state's fairgrounds to accommodate patients, while capacity in El Paso, Texas, is so overtaxed that a county judge imposed stay-at-home orders. Elsewhere, though, and as a whole, hospitalizations are nowhere near where they were during the previous big outbreaks. As a result, there is a risk that the administration, governors and the public misinterpret the severity of this latest wave or downplay the danger beyond a few hotspots. This would be a mistake, and a good look at the data shows why.

During the first wave — which was centered around the New York area from March 3 to June 11 — COVID-19 case counts led hospitalizations by about a week. That gap stretched to about two weeks during the second "Sun Belt" wave from June 11 to Sept. 14, and has now grown to an even longer three weeks in the current third wave. It also appears that the ratio of people in the hospital to the number of positive cases has fallen dramatically in the second and third wave. Here is where the risk of complacency rises.

There are several ways to explain this evolution. First, it is very likely that the number of infections in the first wave were significantly undercounted. I personally know three friends who had mild COVID-19 symptoms very early in the pandemic — from loss of smell and taste to cough, a fever and feeling fatigued — but never got an official diagnosis. This was not only driven by the fact that we did not have access to routine tests and facilities at first, but also, as the case with my friends suggests, many never got checked out to begin with.

Second, the latest wave is driven by younger individuals. While there is risk of severe COVID-19 and "long COVID" in this group, they have a much lower rate of hospitalizations. But they can certainly still spread the disease. Given the incubation period for the virus and the fact that many younger people are likely to be asymptomatic, we would expect many of them to pass on the infection to older members of their families without realizing it. In time, as more elderly people become sick, you'd expect to see an increase in hospitalizations.

Another key difference from prior waves is our increased knowledge of COVID-19 and how to treat it. This has made us more stringent in deciding who gets hospitalized. During the first wave, clinicians had no idea what they were dealing with and outpatient settings didn't know how to handle patients with moderate to severe illness. So the hospitalization rate was much higher. This time around, people who are being hospitalized are likely to have much more severe cases of the disease, which means a bigger strain on intensive-care units. The good news is that mortality rates are likely to be lower this time around as we already have better treatments and clinical management has evolved significantly. But hospitals may still be just as burdened, raising the prospect of delays in elective procedures and other care.

This latest COVID-19 wave isn't taking the same course as the prior ones, but it looks likely to end up with the same result or worse: an acute health crisis in hospitals. How can we avoid this? Proper mitigation tactics — masking, social distancing, hand-washing — should be standard operating procedure. But it may take more than that.

In the coming winter months, we will tend to gather more indoors, where the virus has a very a good chance of being transmitted, while our immune systems will become less capable of fighting invading pathogens. A vaccine won't be ready for broad deployment until well into 2021, assuming current clinical trials of experimental vaccine technologies work. States and local governments will likely need to put curbs on people mixing. Given the experience in Europe, lockdowns — or something very close to that — may be the only option.

Sam Fazeli is senior pharmaceuticals analyst for Bloomberg Intelligence and director of research for EMEA.

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