TORONTO -- With much of the world struggling financially and mentally in self-isolation and lockdowns, people around the world are undoubtedly looking forward to the end of such unprecedented measures.

But according to analysis by Harvard researchers, the best strategy for beating COVID-19 probably isn’t one extended period of physical distancing, but several staggered periods, with time in between to allow immunity to take hold in the population.

The research, described in the Harvard Gazette ahead of being peer reviewed, posits that this strategy could “avoid overwhelming hospitals while allowing immunity to build in the population.”

The problem with locking everyone down for an extended period and then allowing them to roam free again is that this could result in a dramatic resurgence of the virus, with cases potentially soaring to new peaks sometime afterwards, according to the research.

Researchers are concerned that, while physical distancing is the best way to flatten the curve of the outbreak, there is very little immunity to the virus being developed among those who are never exposed while in isolation.

Researchers at the Harvard T.H. Chan School of Public Health focused on the COVID-19 situation in the U.S., using mathematical models to assess different potential outcomes based on different potential strategies that could be used there.

They “assessed that one-time interventions will be insufficient to maintain COVID-19 prevalence,” based on the capabilities of the U.S. system.

“Intermittent distancing measures can maintain control of the epidemic,” the research reads, “but without other interventions, these measures may be necessary into 2022.”

The U.S. is now the epicentre of the pandemic, with more than 380,000 cases and around 12,000 deaths.

These intermittent distancing methods would mean enforcing physical distancing until the caseload of patients eases up, then re-enforcing physical distancing again if the case load rose again past a certain threshold. The theory posits that the time in between lockdowns would become longer as more of the population developed immunity and the health care system worked on medical treatments, until finally the case load dropped off completely.

The research also found that the duration of physical distancing potentially needed is different depending on whether the virus is equally potent all year, or if it is a seasonal ailment that is stronger at different times of the year.

Less of these measures will be needed if the U.S. is able to increase their critical care abilities. Doubling the number of critical-care beds in the hospital system changed the predicted data, showing that bouts of intermittent physical distancing could end in 2021, as opposed to extending for another year.

With no physical distancing at all, the models predict that the U.S. epidemic would be over in the fall — but with an extreme increase in deaths, and a wholly overwhelmed health care system.

The research was released as an academic preprint this week, and has still not been peer reviewed, which means it is too soon to guide clinical practice. But according to Sarah Fortune, chair of the Harvard Chan School’s Department of Immunology and Infectious Diseases, the research could present one of the most realistic available strategies for the coming days, the Harvard Gazette reports.

“The limits of what we can achieve — even locally, in terms of COVID control — is set by the weakest health care systems globally,” said Fortune in a media conference call Thursday morning, referring to how more fragile health care systems could re-expose a country on its way to recovery.

The only option isn’t to simply switch from a full lockdown to completely open streets and businesses again and keep repeating that, however.

An editorial in the Washington Post written by three Harvard researchers from the Harvard T.H. Chan School of Public Health, including one of the central authors of the new research, proposed that certain businesses could reopen slowly before others, depending on different risk factors. For example, schools may be able to reopen before restaurants if it is determined that children are significantly less likely to carry and pass on the virus.

The development of a vaccine or other significant medical intervention would change things, but as of yet, physical distancing is still the greatest weapon the world has against the spread of virus.