"If we were to see the number of deaths from Covid down to what we see on an annual basis for flu — somewhere in the 20,000-a-year range — we’ll then say that the pandemic is clearly over," said Dr. Eric Toner, a senior scholar at the Johns Hopkins Center for Health Security at the Bloomberg School of Public Health. Rachael Piltch-Loeb, a research associate at the Harvard T.H. Chan School of Public Health, said that in declaring the pandemic over now, it "seems like we are endorsing this level of disease burden and mortality associated with the virus." And Dr. Kavita Patel, a primary care physician who was a policy adviser during the Obama administration, said the virus has to become more predictable before the pandemic can be considered over. "We need to have some regular patterns, kind of like the flu, so that we can expect certain timing for sickness, certain timing for hospitalizations," she said. Given that's not the case, Patel said, she found Biden’s declaration "a bit disturbing to hear."