As COVID-19 Infections Rise, Patients Are Getting Younger

The trend, which may reflect growing defiance of social distancing in some age groups, implies a lower death rate

By Jacob Sullum of Reason. Excerpt:

"If rising infections in states such as Texas, California, Arizona, and Florida (which yesterday saw a record increase in new confirmed cases) represent a new normal rather than a one-time jump tied to social gatherings on Memorial Day weekend, it will be hard to put the genie back in the bottle, regardless of any legal restrictions politicians decide to reimpose. Given the impracticality of mass enforcement, social distancing has always required voluntary compliance, and the willingness to comply seems to be waning, partly because of sheer impatience but also because the experience with ham-handed, economically devastating, and frequently arbitrary lockdowns has left many people bitter and disinclined to follow official recommendations.

Assuming that large numbers of Americans are not willing to sit tight until vaccines and/or better treatments can be deployed, what will that mean for the COVID-19 death toll? On that score, there is some reason for (relative) optimism.

While I could not find data breaking down new Texas cases by age, the changing distribution of total cases confirms Abbott's point that newly infected people are younger now than they were earlier in the epidemic. As of yesterday, people older than 65 accounted for 15 percent of total confirmed cases in Texas, down from 22 percent on April 21. The share of cases involving people younger than 40 rose from 32 percent to 41 percent during the same period. Consistent with Abbott's gloss, the biggest jump was in 20-to-29-year-olds, whose share of all confirmed cases rose from 13 percent to 17 percent.

Those comparisons understate the change in recently detected infections, which is the relevant consideration in projecting COVID-19 deaths. In Florida, the median age of newly identified patients plummeted from 65 in early March to 35 last week. In California, according to an analysis released last week, 44 percent of newly diagnosed cases involved people 34 or younger, up from 29 percent a month earlier. The share of new cases involving people older than 50, meanwhile, fell from 46 percent to 30.5 percent.

Why is that good news? Last month the U.S. Centers for Disease Control and Prevention (CDC) estimated that the risk of death for people with COVID-19 symptoms is just 0.05 percent among patients younger than 50. That risk rises to 0.2 percent among 50-to-64-year-olds and 1.3 percent among people 65 or older. In other words, those reckless idiots getting together in bars are correct in thinking that the risk for them is negligible, even if they overlook the fact that the risk for the oldest age group is much higher—26 times as high, according to the CDC's estimate.

While recent increases in COVID-19 infections can be expected to result in some additional deaths in the next few weeks, the consequences will not be nearly as bad as they would be if the new patients were older. The changing age distribution of cases helps explain why the nationwide tally of daily COVID-19 deaths, which has fallen dramatically since April, continued to decline long after states began lifting their lockdowns at the end of that month. Youyang Gu's epidemiological model, which has a good track record of predicting COVID-19 fatalities, currently projects that daily deaths in the United States will continue to decline until early July, then rise through mid-August, exceeding the current level by late July, before declining again through September, dropping below the current level by the middle of that month.

"With younger age of recent infections in at least some places such as Florida," former CDC Director Tom Frieden tweeted this week, "expect a lower death rate in this wave…until the 20-40-year-olds who are infected today go on to infect others." The implication is that we will eventually see a big surge in COVID-19 deaths as younger, healthier Americans relatively unscathed by the virus pass it on to others who are more vulnerable. But that is not a foregone conclusion. As always, it depends on the precautions that people take, and the onus for those seems to be shifting from the population at large to people in high-risk groups. We can debate whether or not that is fair, but it will not change the reality."