The Biden administration is concerned about the alarm it predictably generated by emphasizing the danger of COVID-19 cases in people vaccinated against the disease. But even as the administration pushes back against overwrought news coverage of its justification for recommending that vaccinated Americans resume wearing face masks in public places, it continues to exaggerate the risk of "breakthrough" infections.
"The White House is frustrated with what it views as alarmist, and in some instances flat-out misleading, news coverage about the Delta variant," CNN's Oliver Darcy reports. "The media's coverage doesn't match the moment," an unnamed "senior Biden administration official" told Darcy. "It has been hyperbolic and frankly irresponsible in a way that hardens vaccine hesitancy. The biggest problem we have is unvaccinated people getting and spreading the virus."
In what sense has the coverage been hyperbolic and irresponsible? "At the heart of the matter is the news media's focus on breakthrough infections, which the CDC has said are rare," Darcy explains. "In some instances, poorly framed headlines and cable news chyrons wrongly suggested that vaccinated Americans are just as likely to spread the disease as unvaccinated Americans." But as Darcy notes, "vaccinated Americans still have a far lower chance of becoming infected with the coronavirus" than unvaccinated Americans and therefore "are responsible for far less spread of the disease."
Where did reporters get the idea that vaccinated carriers account for a much larger share of virus transmission than they actually do? Possibly from Rochelle Walensky, director of the Centers for Disease Control and Prevention (CDC). For "every 20 vaccinated people," Walensky told CNN's John Berman last Wednesday, "one or two of them could get a breakthrough infection." Based on studies conducted before and after vaccines were approved by the Food and Drug Administration, that estimate is off by at least an order of magnitude. In fact, it implies that vaccinated people face a higher risk of infection than unvaccinated people do.
Ben Wakana, deputy director of strategic communications and engagement for the White Office COVID-19 Response Team, offered a similar risk estimate on Friday. "Let's be clear," he tweeted. "If 10 vaccinated people walk into a room full of COVID, about 9 of them would walk out of the room WITH NO COVID. Nine of them."
Both of these estimates seem to be based on a misconception about the effectiveness rates reported in vaccine studies. When a vaccine is described as 90 percent effective against infection, that does not mean 10 percent of vaccinated subjects were infected. Rather, it means the risk of infection among vaccinated people was 90 percent lower than the risk among unvaccinated people.
What does that mean in terms of absolute risk? In one U.S. study of adults who had received the Pfizer or Moderna vaccines, the incidence of positive COVID-19 tests among fully vaccinated subjects was 0.048 per 1,000 person-days, compared to 0.43 per 1,000 person-days among the unvaccinated controls, yielding an effectiveness rate of 89 percent. A study of U.S. health care workers put the incidence of infection at 1.38 per 1,000 person-days when the subjects were unvaccinated, compared to 0.04 per 1,000 person-days when they were fully vaccinated, yielding an effectiveness rate of 97 percent.
Wakana, by contrast, is saying vaccinated people face a 10 percent risk of infection every time they "walk into a room full of COVID." Although he thinks that is reassuring, it is actually quite alarming, suggesting that vaccination somehow makes people more vulnerable to infection. Even in studies where the especially contagious delta variant accounts for most cases, infection rates among unvaccinated people over an extended period of time are far lower than Wakana's estimate of the risk for vaccinated people from a single visit to an indoor space where carriers are present.
Given Wakana's gross exaggeration of the breakthrough infection risk, his criticism of news outlets he charges with undermining public confidence in vaccines is hard to take seriously. "VACCINATED PEOPLE DO NOT TRANSMIT THE VIRUS AT THE SAME RATE AS UNVACCINATED PEOPLE," he tweeted a few hours before claiming that one in 10 vaccinated people will be infected if they enter a COVID-tainted room. "IF YOU FAIL TO INCLUDE THAT CONTEXT YOU'RE DOING IT WRONG."
Wakana was responding to this New York Times tweet: "The Delta variant is as contagious as chickenpox and may be spread by vaccinated people as easily as the unvaccinated, an internal C.D.C. report said." Wakana is right that the missing context—the fact that vaccinated people are highly unlikely to be infected in the first place, even by the delta variant—made that tweet potentially misleading. But it's true that the CDC has suggested the delta variant "may be spread by vaccinated people," assuming they defy the odds by becoming infected, "as easily as the unvaccinated."
When it published a study of a COVID-19 outbreak in Provincetown, Massachusetts, on Friday, the CDC reported that it found "similarly high SARS-CoV-2 viral loads in vaccinated and unvaccinated people," which it said "raised concern that, unlike with other variants, vaccinated people infected with Delta can transmit the virus." It remains unclear whether that finding means vaccinated people infected by the delta variant are as likely to spread it as unvaccinated people.
The CDC cautions that the indicator of viral loads used in the study may be misleading. Assuming that the viral loads in nasal samples from vaccinated people were indeed similar to the viral loads in nasal samples from unvaccinated people, that does not necessarily mean the two groups were equally likely to transmit the virus. Researchers are still trying to figure out how many of the Provincetown cases (if any) were caused by vaccinated carriers. And given that three-quarters of the 469 cases described by the CDC involved "symptoms consistent with COVID-19," the similarity of viral loads in nasal samples may not apply to asymptomatic infections, which easily could have been missed.
Still, the misleading impression left by the New York Times tweet pales in comparison with the blatant misinformation that the Biden administration is disseminating about the risk of breakthrough infections. The CDC and Walensky herself have repeatedly noted that breakthrough infections remain "rare," notwithstanding the delta variant, and that unvaccinated people account for "the vast majority" of transmission. Those observations cannot be reconciled with the notion that one in 10 vaccinated people who enter a room where COVID-19 carriers are present will emerge with an infection.
Wakana also faulted The Washington Post for this tweet: "Vaccinated people made up three-quarters of those infected in a massive Massachusetts covid-19 outbreak, pivotal CDC study finds." That gloss was "completely irresponsible," he said, because "the CDC made clear that vaccinated individuals represent a VERY SMALL amount of transmission occurring around the country." He added that "virtually all hospitalizations and deaths continue to be among the unvaccinated," which confirms that vaccines still provide excellent protection against life-threatening symptoms. Wakana also could have noted a caveat that the CDC study mentions: Even though their risk of infection is very low, vaccinated people are bound to represent a growing share of infections as vaccination rates rise, and the vaccination rates in both Massachusetts and Provincetown are especially high.
But at least the Post accurately reported what the CDC's Provincetown study said. Wakana's statement about the probability of a breakthrough infection, by contrast, misrepresents what vaccine studies tell us.
Furthermore, the CDC's rationale for resuming universal masking itself implies that vaccinated people are playing a significant role in spreading the delta variant. As Darcy notes, "the CDC said it was changing its mask guidance because of the new data regarding rare instances in which a vaccinated person becomes infected and can then spread the virus." Former Baltimore Health Commissioner Leana Wen, now a CNN medical analyst, suggests that explanation was misleading, if not disingenuous.
"They got it wrong," Wen told Darcy. "The reason why the guidance is changing is that COVID-19 is spreading really quickly, delta is a big problem, and the reason for the spread is because of the unvaccinated." In Wen's view, blanket mask mandates are appropriate because it is not feasible to exempt vaccinated people. But the CDC made no reference to that issue when it published its new guidance, which recommends voluntary precautions that it thinks vaccinated people should take, regardless of whether state or local governments decide to require masks.
The CDC, in short, said vaccinated people should wear masks because of the danger they pose to others, which depends on the still very low probability that they will be infected as well as the still uncertain probability that they will transmit the virus if they are infected. Walensky defended that new position by grossly exaggerating the risk of breakthrough infections, and Wakana followed suit, even while attempting to reassure the public about the effectiveness of vaccines and emphasizing that "vaccinated individuals represent a VERY SMALL amount of transmission." Now the Biden administration is dismayed at the alarmist reporting it invited, which it rightly worries will deter people from being vaccinated. One need not give news outlets a pass for misleading the public to recognize that they were taking their cues from federal officials.