![]() ![]() With each major wave, “the virus has only gotten more transmissible,” says Ruth Karron, a vaccine researcher at Johns Hopkins. Despite a relatively slow rate of mutation at the beginning of the pandemic, it soon evolved into variants that are more inherently contagious and better at evading immunity. This coronavirus has also proved a wilier opponent than expected. Even vaccinating the whole world would not eliminate COVID transmission. When you saw 95 percent against mild disease, with the trials done in December 2020, we should have said right then this is not going to last,” says Paul Offit, the director of the Vaccine Education Center at Children's Hospital of Philadelphia. “Right at the beginning, we should have made that very clear. Flu, the four common-cold coronaviruses, respiratory syncytial virus (RSV), and others all reinfect us over and over again. But immunity to infection is not durable against common respiratory viruses. Breakthrough cases were downplayed as very rare. In early 2021, the initially spectacular vaccine-efficacy data bolstered optimism that vaccination could significantly dampen transmission. The challenge of driving down COVID transmission has also become clearer with time. The tens of thousands of recorded cases-likely hundreds of thousands of actual cases every day-also add to the burden of long COVID. These are estimates, because lack of testing hampers accurate case counts for both diseases, but COVID’s higher death toll is a function of higher transmission. In contrast, flu sickens an estimated 10 to 20 percent of Americans a year. Going forward, COVID might continue to infect 50 percent of the population every year, even without another Omicron-like leap in evolution. But across the whole population, COVID is still killing many times more people than influenza is, because it is still sickening so many more people.īedford told me he estimates that Omicron has infected 80 percent of Americans. Since then, widespread immunity, better treatments, and the less virulent Omicron variant have together pushed the risk of COVID to individuals down to a flu-like level. We largely tolerate, the thinking went, the risk of flu without major disruptions to our lives. I keep returning to the flu because, back in early 2021, with vaccine excitement still fresh in the air, several experts told my colleague Alexis Madrigal that a reasonable threshold for lifting COVID restrictions was 100 deaths a day, roughly on par with flu. This too is approximately three times that of a typical flu year. ![]() Trevor Bedford, a virologist at the Fred Hutchinson Cancer Center, estimates that COVID will continue to exact a death toll of 100,000 Americans a year in the near future. (The elderly who mount weaker immune responses remain the most vulnerable: 88 percent of COVID deaths so far in September have been in people over 65.) With a public weary of pandemic measures and a government reluctant to push them, the situation seems unlikely to improve anytime soon. The virus evolves too rapidly, and our own immunity to COVID infection fades too quickly-as it does with other respiratory viruses-even as immunity against severe disease tends to persist. In time, it also became clear that immunity to COVID is simply not durable enough for elimination through herd immunity. “I don’t think that was ever really practically possible,” says Stephen Morse, an epidemiologist at Columbia. The virus that came out of Wuhan, China, in 2019 was already so good at spreading-including from people without symptoms-that eradication probably never stood a chance once COVID took off internationally. This shifting of goal posts is, in part, a reckoning with the biological reality of COVID. If you notice, no one’s wearing masks,” the country was still recording more than 400 COVID deaths a day-more than triple the average number from flu. When President Joe Biden declared this week, “The pandemic is over. Instead, COVID has settled into something far worse than the flu. When this too became impossible, we accepted that the virus would still circulate but imagined that it could become, optimistically, like one of the four coronaviruses that cause common colds or, pessimistically, like something more severe, akin to the flu. When this became impossible, we hoped instead for elimination: If enough people got vaccinated, herd immunity might largely stop the virus from spreading. When is the pandemic “over”? In the early days of 2020, we envisioned it ending with the novel coronavirus going away entirely. ![]()
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