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October 7, 2021

Is the delta surge truly ending? Here's why some experts aren't so sure.

Daily Briefing

    With Covid-19 cases, hospitalizations, and deaths declining across the country, some people are hopeful about a potential end to the delta surge. However, public health experts continue to encourage safety measures and vaccinations to mitigate another potential winter surge.

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    Is the delta surge declining?

    According to the New York Times, delta-driven coronavirus cases, hospitalizations, and deaths are declining. Since Sept. 1, the number of daily new Covid-19 cases in the United States has decreased by 35%. In the past two weeks alone, the number of new daily cases has fallen by 24% to around 101,000.

    In addition, new Covid-19 deaths have decreased by 12% to 1,829 a day, and hospitalizations have decreased 20% to fewer than 75,000 a day—a first since early August, the Times reports.

    "Barring something unexpected," Scott Gottlieb, a former FDA commissioner, said, "I'm of the opinion that this is the last major wave of infection."

    Edwin Michael, a professor of epidemiology at the University of South Florida, agreed with Gottlieb's assessment, saying, "[T]his might be the last wave, pending any new variants that arrive, and the boosters will help with that."

    According to STAT News, some experts suggest that the United States has reached an "inflection point," in which the coronavirus is gradually transitioning from an epidemic phase to an endemic phase. As an endemic virus, the coronavirus will still cause infection, disease, and death, but it will be more manageable.

    When asked whether Covid-19 could be endemic, Stephen Kissler, an epidemiologist at Harvard University's T.H. Chan School of Public Health, said, "We've still got a little work left to do, but my hope is that we're approaching something ever closer to normalcy."

    Health experts continue to urge caution

    However, even with the delta surge on an apparent decline, many public health experts continue to urge caution, saying that the pandemic is still a threat, the Times reports.

    "We don't want to celebrate even though we feel like we're on the back end of this surge—we learned our lesson from doing that," said Kirsten Bibbins, an epidemiologist and physician at the University of California, San Francisco. "[I]n this pandemic, you're always waiting for the other shoe to drop."

    Ali Mokdad, an epidemiologist at the University of Washington, agreed. "We're not out of danger," he said. "This virus is too opportunistic and has taught us one lesson after another."

    Mokdad said he was worried people would disregard public safety precautions by wearing masks less often and traveling more, just as they did when earlier surges declined—potentially fueling a jump in cases in December and January.

    Some experts are also concerned about the potential emergence of a new coronavirus variant that could kick-start another surge, much like the delta variant did at the beginning of the summer.

    "There were similar conjectures [about the pandemic ending] before the delta variant appeared and knocked all our assumptions for a loop," said Stephen Morse, an epidemiologist at Columbia University Medical Center. "We don't know whether [a new variant will emerge], but we weren't expecting delta either."

    In addition, there is still the possibility of a surge in cases during the winter months, STAT News reports.

    According to Sen Pei, who studies the transmission dynamics of infectious disease at the University of Columbia's Mailman School of Public Health, viruses survive better in cooler, drier weather, and people will gather indoors more frequently in the fall and winter. Holiday gatherings could also lead to more close social contact, further increasing the risk of spreading the virus.

    Vaccination remains a necessity to combat surges

    Most Covid-19 deaths during the latest surge were among the unvaccinated, the Times reports. Today, around 68 million eligible Americans remain unvaccinated—leaving the United States vulnerable to future surges.

    In particular, areas with low vaccination rates, along with a lack of public safety precautions, may be more likely to experience Covid-19 surges in the future, STAT News reports. According to data from the University of Iowa, rural Americans are already twice as likely to die from Covid-19 than urban Americans.

    "It is becoming clearer that any challenge to hospital capacity this fall and winter is likely to be dictated by regional vaccination rates," modelers at the Children’s Hospital of Philadelphia’s PolicyLab said.

    Currently, vaccination rates in the United States have slowed to fewer than 700,000 doses a day, the Commonwealth Fund reports.

    However, a simulation model of 10 states by the Commonwealth Fund found that increasing daily vaccination rates by 50% over the pace they were at in the last week of August would lead to 344,341 fewer Covid-19 cases; 19,500 fewer hospitalizations; and 6,900 fewer deaths across the next six months. These potential reductions were largely concentrated in the Southern states included in the model, such as Texas and Florida.

    "Vaccination works best as prevention," the Commonwealth Fund said. "Quickly increasing population immunity now can prevent needless Covid-19 hospitalizations and deaths while keeping hospital beds open and staffed for people with other serious health problems." (Hassan, New York Times, 10/6; Joseph, STAT News, 10/6; Leonhardt, New York Times, 10/4; Putka, MedPage Today, 10/5; Carbajal, Becker's Hospital Review, 10/5; Schneider et al., The Commonwealth Fund, 10/5)

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