Many Americans do not have much faith in the government's COVID-19 advice, which has changed repeatedly during the pandemic, often for questionable reasons. It has not helped that local, state, and federal public health officials have defended their positions with disingenuous arguments or misrepresented the scientific evidence.

survey conducted last spring by the Robert Wood Johnson Foundation and Harvard's T.H. Chan School of Public Health found that just 52 percent of Americans had "a great deal" or "quite a lot" of trust in recommendations from the Centers for Disease Control and Prevention (CDC). Other public health authorities had even lower ratings: 44 percent for local health departments, 41 percent for state health departments, 40 percent for the U.S. surgeon general, 37 percent for the Food and Drug Administration (FDA), and 33 percent for the U.S. Department of Health and Human Services, for example.

New York Times health and science reporter 

Is it really so surprising, then, that Americans feel bewildered and bamboozled, even enraged, by rapidly changing rules that have profound implications for their lives?"

There is some truth to this. Emerging evidence concerning the especially contagious delta variant and the possibility that vaccine effectiveness wanes over time, for example, has given rise to lively debates about the merits of new masking guidelines and booster shots. Evidence that face masks play an important role in reducing virus transmission, which was pretty meager early in the pandemic, has been reinforced by more recent studies, although it is still not strong enough to persuade many skeptics, including some who are familiar with the scientific literature.

But Mandavilli completely overlooks other factors that help explain why so many Americans are disinclined to accept the government's guidance as gospel. Public health advice is not simply a function of science. It incorporates cost-benefit analyses and value judgments on which well-informed people of good faith can honestly differ. Whether "universal masking" in schools makes sense, for instance, depends not only on the uncertain evidence that it prevents outbreaks but on the weight one assigns to the burdens that policy imposes. It also depends on what level of risk is deemed tolerable.

In this case and others, it often seems that public health agencies are working backward, settling on a policy and then searching for evidence to back it up. Anyone who delves into the studies that the CDC cites to justify its recommendation that everyone 2 or older wear face masks in schools and other public settings, regardless of their vaccination status, can see that science is just one element of the agency's deliberative process.

The CDC's initial dismissal of general mask wearing as a precaution against COVID-19 likewise was clearly influenced by nonscientific considerations—in particular, the concern that the practice would aggravate a shortage of masks for health care workers. The agency's reversal of that position in April 2020, although supposedly justified by evolving evidence, officially was driven mainly by concerns about asymptomatic transmission, a danger that had been recognized for months. And while the CDC's double reversal of its mask advice to vaccinated Americans was based on concerns about a new development—the proliferation of the delta variant, coupled with evidence that vaccines are less effective at preventing infection by it—there was legitimate disagreement about the merits of both shifts.

As far as Mandavilli is concerned, the CDC has simply been following the science all along, a point that Americans are too ignorant to recognize. "One jarring backtrack was the mask guidance by the Centers for Disease Control and Prevention," she writes. "The agency said in May that vaccinated people could drop their masks, advice that helped set the stage for a national reopening. Officials did not emphasize, or at least not enough, that the masks could be needed again. Now, with a new surge in infections, they are." Mandavilli thus takes as a given the very point that critics of the CDC's latest guidance contest.

State policy likewise has been driven by scientifically questionable reasoning. After California banned outdoor restaurant dining in late 2020, the state's health secretary admitted the policy was not based on evidence that the newly prohibited activity posed a significant risk of virus transmission. The real aim, he said, was to discourage Californians from leaving home.

Around the same time, San Mateo County Health Officer Scott Morrow, an early advocate of lockdowns in the San Francisco Bay Area, complained that there was little rhyme or reason to the new restrictions imposed by Gov. Gavin Newsom, which ultimately delivered no perceptible public health benefit. "I am aware of no data that some of the business activities on which even greater restrictions are being put into place with this new order are the major drivers of transmission," Morrow said. "I'm not sure we know what we're doing."

Morrow, a physician with a public health degree who has been San Mateo County's health officer since 1992, presumably cannot be accused of misunderstanding how science works. His complaint was that California's policies were not justified by the evidence.

The distrust provoked by disingenuous arguments and empirically shaky policies has been compounded by official statements with no basis in fact. Early in the pandemic, then–Surgeon General Jerome Adams flatly asserted that face masks "are NOT effective in preventing [the] general public from catching #Coronavirus." After the CDC changed its advice on masks, public health officials erred in the opposite direction. Last fall, in his zeal to promote face masks as "the most important, powerful public health tool we have," then–CDC Director Robert Redfield claimed they offered more effective protection than vaccines would. The current CDC director, Rochelle Walensky, has grossly exaggerated the risk of outdoor transmission and the danger posed by breakthrough infections, blatantly mischaracterizing the scientific evidence.

Americans should be able to rely on public health officials for accurate summaries of COVID-19 research. Episodes like these suggest they can't, which is at least as big a problem as the public's lack of appreciation for scientific uncertainty.

Mandavilli likewise blames the public rather than the government for the skepticism inspired by the FDA's delay in fully approving COVID-19 vaccines. Today the FDA finally gave full approval to Pfizer's two-dose COVID-19 vaccine, eight months after it granted an emergency use authorization. "Some holdouts found it suspicious that the vaccine was not formally approved yet somehow widely dispensed," Mandavilli  writes. "For them, 'emergency authorization' has never seemed quite enough."

But surely it was reasonable to wonder why the FDA—despite expressing confidence in the safety and efficacy of vaccines and allowing millions of injections, which generated reams of data to supplement the evidence from clinical trials—waited so long to address the concern that Mandavilli seems to view as frivolous. While full approval may not persuade committed anti-vaxxers, it could have made a decisive, potentially lifesaving difference for many waverers. If the delay led to avoidable COVID-19 deaths, the FDA bears some responsibility for that outcome.

Mandavilli does fault "health officials" for failing to take "full advantage" of their ability to counteract COVID-19 "misinformation," which she says offered "a powerful opportunity to fill in the knowledge gaps for many Americans." But while rebutting misinformation certainly is preferable to suppressing it through government-encouraged censorship, there is always a danger that health officials themselves will err, evincing unjustified confidence and mistaking their own opinions for incontrovertible fact.

Mandavilli, for example, thinks it's a fact that universal masking is "needed," which implies that people who disagree are disseminating misinformation. That attitude is hardly consistent with the epistemological modesty that seems appropriate in light of the scientific uncertainty she emphasizes.

No comments:

Post a Comment