With H.I.V., Dr. Brandt said, “there were conspiracy theories and a lot of misinformation, but it never had a broadcast system like Covid-19.”
Other pandemics, like this one, were hobbled by what Dr. Snowden calls “overweening hubris,” prideful certainties from experts that add to the frustrations of understanding how and when it will dwindle away.
With Covid, prominent experts declared at first that masks did not help prevent infection, only to reverse themselves later. Epidemiologists confidently published models of how the pandemic would progress and what it would take to reach herd immunity, only to be proved wrong. Investigators said the virus was transmitted on surfaces, then later said that, no, it was spread through tiny droplets in the air. They said the virus was unlikely to transform in a substantial way, then warned of the Delta variant’s greater transmissibility.
“We paid a heavy price for that,” Dr. Snowden said. Many people lost trust in officials amid ever-changing directives and strategies that weakened the effort to control the virus.