A study published yesterday predicts that eventually COVID-19 will be just another endemic virus which circulates in the population but rarely makes anyone seriously ill. How soon we get to that point will depend on the speed of our vaccination rollout.

“The timing of how long it takes to get to this sort of endemic state depends on how quickly the disease is spreading, and how quickly vaccination is rolled out,” said Jennie Lavine, a postdoctoral fellow at Emory University in Atlanta, who led the study…

While all of these coronaviruses produce a similar immune response, the new virus is most similar to the endemic common cold coronaviruses, Dr. Lavine and her colleagues hypothesized.

The viruses that cause the common cold have already spread to people around the world. Most people are exposed to those viruses for the first time as children when their immune response is strong. And over time, people get reinfected and their immune response to the cold virus gets stronger. The reason the coronavirus is so deadly is because it’s essentially a new virus that is hitting the immune systems of older people who are less able to fight it off. If they’d encountered the same virus as children and built up a resistance, they wouldn’t be so ill now.

Another possible scenario, where the vaccine completely prevents the spread of the virus until it disappears, is less likely in this case:

“The overall intellectual construct of the paper I fully agree with,” said Shane Crotty, a virologist at the La Jolla Institute for Immunology in San Diego.

If the vaccines prevent people from transmitting the virus, “then it becomes a lot more like the measles scenario, where you vaccinate everybody, including kids, and you really don’t see the virus infecting people anymore,” Dr. Crotty said.

It is more plausible that the vaccines will prevent illness — but not necessarily infection and transmission, he added. And that means the coronavirus will continue to circulate.

If the study’s authors are correct, it will take a year or maybe a few to get there but eventually COVID will just be a kind of background noise for most people’s health. When your toddler gets a cold, it will be COVID and they’ll shrug it off and that early exposure will protect them later on. In fact, the story mentions a theory that a deadly pandemic that killed a million people in 1890 was caused by one of the four coronaviruses that cause the common cold. That outbreak ended as people built up a natural resistance.

However, there is a third possibility. The Times quotes Marc Lipsitch of the Harvard School of Public Health who suggests it’s possible the coronavirus could turn out to be more like the seasonal flu, i.e. something that has good years and bad years. “Their prediction of its becoming like common cold coronaviruses is where I’d put a lot of my money,” Lipsitch said, but he added, “But I don’t think it’s absolutely guaranteed.”