What will Omicron’s decline look like? Hard to say.

It appears that Omicron may have peaked in several urban centers on the East Coast. But experts aren’t sure what the coronavirus variant’s downward path will look like across the U.S.

According to a January 14, 2022, article in The Atlantic, the back ends of outbreak curves depend on the amount of immunity in a given population, on the nature of the virus, on measures to control the spread of disease, and on people’s behaviors.

Experts quoted in the article said that Omicron could drop sharply, but it could also plateau or even increase again. They noted that although Omicron peaked and plunged fairly quickly in South Africa, things could play out differently in the U.S. because, although the country is more vaccinated than South Africa, it also has an older and therefore more vulnerable population. There are other differences as well, such as the fact that Omicron hit South Africa as summer was beginning, whereas it is circulating in the U.S. during winter, when people spend more time indoors.

“I think at least the initial downslope will be precipitous,” said Yonatan Grad, Melvin J. and Geraldine L. Glimcher Associate Professor of Immunology and Infectious Diseases at Harvard T.H. Chan School of Public Health. But he noted that as the virus moves into more rural, less populated parts of the U.S., it will peak at different times in different places, which could slow and lengthen Omicron’s overall decline.

Read article in The Atlantic: The Worst of the Omicron Wave Could Still Be Coming