• Social distancing measures could be necessary on and off through 2022, according to infectious-disease researchers at Harvard.
• To prepare for future waves of infections and build “herd immunity,” the researchers said countries should expand their critical care capacities and look for new treatments.
• Widespread coronavirus testing should also continue at least through 2024, to plan social distancing measures properly.

As parts of the US reach the peak of their first wave of coronavirus infections, officials and experts are trying to discern what lies on the other side. According to infectious-disease researchers at Harvard, that could be another two years of on-and-off social distancing.

In an analysis published Tuesday in the journal Science, they modeled the future of the virus that causes COVID-19 based on the behavior of two previous human coronaviruses.

After the initial wave, they projected that the coronavirus will come back in “recurrent wintertime outbreaks.” Though they could be less severe than the first wave, new outbreaks could still overwhelm hospitals.

“To avoid this, prolonged or intermittent social distancing may be necessary into 2022,” the researchers wrote.

They estimated that social distancing measures would need to be in place between 25% to 75% of that time, given the current critical care capacity of the US.

Testing, treatments, and expanded critical care could speed up the end of COVID-19

Even if the virus seems to disappear, widespread testing should continue, the researchers wrote, “since a resurgence in contagion could be possible as late as 2024.”

That testing will help officials “time the distancing measures correctly and avoid overshooting critical care capacity,” they added.

Once the first wave of infections has passed, the researchers recommended that countries focus on finding COVID-19 treatments and expanding the capacities of their critical care systems. Such measures would help countries prepare for future waves of the virus.

“To shorten the SARS-CoV-2 epidemic and ensure adequate care for the critically ill, increasing critical care capacity and developing additional interventions are urgent priorities,” the researchers wrote. “New therapeutics, vaccines, or other interventions such as aggressive contact tracing and quarantine… could alleviate the need for stringent social distancing.”

Expanding critical care capacities to handle more patients could also help populations gain the protection of “herd immunity” faster.

A population has “herd immunity” when enough of its members become immune that a virus has little opportunity to spread to new people. For now, herd immunity is a distant horizon. As more people become infected and recover in future coronavirus waves, the immune portion of the population will grow.

But how the virus spreads over the next five years depends mostly on how long a recovered person’s immunity lasts. If an individual becomes vulnerable to re-infection just one year after recovering from illness, it will take much longer to build herd immunity and end the virus’ spread.

That timeline is still unclear, along with much of how COVID-19 immunity works. US officials are preparing to make antibody blood tests available, which can help experts learn more about resistance by detecting antibodies.

In the meantime, countries could implement more periods of social distancing or lockdowns like the ones in place across most of the world.

“Social distancing measures may need to last for months to effectively control transmission and mitigate the possibility of resurgence,” the Harvard researchers wrote.