With the Delta variant, people now have to make different calculations about personal risk. The problem is that the parameters are not yet fully known.
By Benjamin Wallace-Wells July 31, 2021 the The New Yorker
So many things have gone wrong in the American response to the pandemic, but two important things have gone right: scientists have developed a vaccine, and older Americans have got it. Seventy-six per cent of Americans between the ages of fifty and sixty-four have received at least one dose, according to the Mayo Clinic’s vaccination tracker. Between the ages of sixty-five and seventy-four, it’s ninety-one per cent, and among those over the age of seventy-five it’s eighty-seven. (Slightly smaller numbers have received a full, two-dose vaccination.) Blue states have been a little more compliant, and the red states a bit less, but the regional differences among older Americans haven’t been so big. Even in deep-red South Carolina, ninety-three per cent of senior citizens have received at least one dose. In Nebraska, ninety-five per cent have, and the numbers in Idaho and Florida are ninety per cent and ninety-eight per cent, respectively. There was no mass campaign to combat disinformation among the aged, no detectable conversion of anti-vaxxer senior citizens to pro-science liberals. “They have the same worries about the vaccine, but when they did the risk-benefit it was just so clear to them that the risks were so severe,” Mollyann Brodie, who runs public-opinion surveys on the pandemic for the Kaiser Family Foundation, told me. There is a dark irony in this. For months, conservative television hosts have fulminated to a largely older audience about the madness of the vaccine campaign: Tucker Carlson has scrunched up his face and said the word “Fauci” with Old Testament menace; a renegade ex-Times reporter named Alex Berenson has rattled off statistics in a rhythm that sounds designed to perplex. Through it all, this older audience has tuned in loyally, from armchairs in Idaho and South Carolina, while already fully vaccinated—their cells displaying the telltale protein piece, antibodies formed and ready. They have taken the campaigns on television neither literally nor seriously; they have understood that it is for show.
The broadly effective vaccination of older Americans and the embarrassingly ineffective vaccination of everyone else, just as the highly contagious Delta variant has won out in the microbe wars, has given the pandemic its current uncertainty: cases are rising sharply, but deaths are not. One reason for this strange situation is how heavily the coronavirus’s risk of death is concentrated among older people––most of whom are now vaccinated. At the outset of the pandemic, the Dartmouth economist Andrew Levin had calculated the mortality risk from covid-19 by age (he originally used data from South Korea, Iceland, Sweden, and New Zealand , because it was the first available), creating tables that the Centers for Disease Control and Prevention still uses. Over the phone, just back from a congressional hearing, he read me the numbers: at the age of thirty, one in five thousand infected and unvaccinated Americans might be expected to die; at forty, one in fifteen hundred; at seventy, one in forty; at eighty, nearly one in ten, close to five hundred times the mortality risk of a thirty-year-old. Vaccinating the elderly was the essential prophylaxis—it kept the vulnerable safe and gave everyone else a little more freedom. Levin did a calculation for me and estimated that, even though just half of Americans over all have been fully vaccinated, those vaccines (concentrated among the most vulnerable) have cut the infection-fatality rate by about seventy-five per cent. William Hanage, an epidemiologist at Harvard, told me, “The relationship between cases and outcomes—be they hospitalizations or deaths—has been altered. It is no longer the same.”
This is what made everyone pretty sanguine at the beginning of the summer. As the Delta variant has spread, the relationship between the virus and the most severe illnesses is different from what it has been in the past. Since mid-June, the seven-day average of new cases in the United States has grown by five hundred and fifty per cent, from about fourteen thousand to about seventy-seven thousand. But the number of deaths is almost exactly the same. In mid-June, the national seven-day rolling average of daily deaths was about three hundred and fifty. On Friday, it was three hundred and one. (That level, according to the Kaiser Family Foundation, means that covid is now just the seventh-leading cause of death—far below heart disease and cancer and also below accidents, strokes, respiratory disease, and Alzheimer’s, and just above diabetes.) The experience of the U.K., where the Delta variant has already peaked, was similar. Michael Osterholm, an epidemiologist at the University of Minnesota who served on the Biden-Harris Transition covid-19 Advisory Board, reviewed with me data from this summer’s U.K. surge, sorted by age group, and compared it with those from that country’s previous surge. The case numbers were about the same, he pointed out. But the deaths? “Way down, way down, way down.”