The discrepancy between the trends for cases and deaths first appeared in June, at a time when cases had plateaued, and it generated a lot of discussion about why the two were diverging — some of it hopeful. Could the novel coronavirus be mutating to become less lethal? (Experts see no evidence of this.) Is everyone benefiting from time outdoors, including a bigger dose of vitamin D? (Again, no clear evidence.) Certainly, treatments for hospitalized patients have improved, but these advances remain incremental. (Dexamethasone, a steroid treatment, reduced mortality from 41 percent to 29 percent in patients on ventilators, one study found.) A more boring, yet likely, explanation is that during our long plateau, increased testing uncovered milder infections — enabling raw numbers of new cases to appear steady even as the true outbreak slowed, thanks to stay-at-home orders.
But the picture has now changed. There’s no more plateau: We have a major outbreak on our hands. Daily case numbers have surged mercilessly, to a record-breaking 65,000 this past week. True, given increased testing, these numbers are not directly comparable to the late-April figure of 35,000 cases in a day; back then, because of a shortfall in testing capacity, we were missing many more infections than we are now.
But test positivity rates are spiking, too. In Arizona, for instance, the figure increased from roughly 5 percent in early May to 20 percent in late June. At the same time, nationwide hospitalization numbers are approaching mid-April levels, and intensive care units are filling up in such states as Florida, Texas and Arizona. The combination of more testing, higher positivity and rising hospitalization is a grim one — a clear signal of extensive community transmission.
In short, the period that might have warranted a degree of optimism has vanished. Deaths have leaped in the past two weeks to an average of 700 daily — and there is no reason to think the rise will stop. The accelerating outbreak is only now showing up in the death numbers because deaths are a “lagging indicator”: It takes awhile from the time patients are infected, to when they are symptomatic and seek testing, to when they are admitted to a hospital. And once in the hospital, patients can experience protracted stays. The result is that deaths reflect viral transmission that occurred two to eight weeks earlier. (Hospital admissions are another lagging indicator, though they provide an earlier signal than deaths.)
Amid the sharp jump in cases, the demographics of the new infections have contributed to the wishful thinking: They have skewed younger. This trend is partly due to increased testing of people with mild or even no symptoms. But with test positivity rising, we know there is more going on. Young people are among those who flocked to bars when they reopened; they’re going back to work or hanging out with friends, and the virus is spreading.
It’s true that older adults are far more likely to die than younger adults — which is why Vice President Pence has said it’s “a good thing” that many new cases involve younger people. But the catch is that our populations are not neatly partitioned into low- and high-risk bubbles. Young people without symptoms can inadvertently transmit to people of every age, including family members, neighbors and co-workers. And what we are seeing in states like Florida is that infections among older people are proving to be yet another lagging indicator: New cases in adults over 65 in that state are belatedly on the rise, from roughly 300 per day in mid-June to more than 1,800 per day in mid-July.
Several states are reporting record highs for daily deaths (Florida had 156 Thursday), the upswing in daily deaths has begun nationally, and ICUs are filling — all this, as states’ responses remain slow and inadequate. Here in Gainesville, Fla., I can, if I wish, go to an indoor fitness class, get my nails done and eat inside at a restaurant. I could make the two-hour drive to Disney World and get in line for a ride (though I will do none of these things).
Modest policy changes, such as encouraging more mask wearing, are almost certainly insufficient to reverse the rapid growth in cases. And in Georgia, where more than 2,800 patients are currently hospitalized, the governor has gone so far as to forbid local mask mandates. With the case numbers we’re seeing, it’s whistling past the graveyard — nearly literally — to celebrate a temporarily low death rate. As the numbers of cases continue to rise, so will the preventable deaths of thousands more Americans.