They, however, noted that countries would need to define for themselves how long the duration of the intervals would last to suit their needs and facilities
Many governments have imposed some form of lockdown to mitigate the transmission of Covid-19.
But policymakers around the world are now weighing the trade-offs between lives and livelihoods to slowly lift those measures as the pandemic weighs heavily on economic activities.
Periods of easing, after intermittent lockdowns, could be an effective strategy to lower Covid-19 related deaths.
Fifty days of strict lockdowns followed by 30 days of relaxation could be useful in minimising fatalities from the novel coronavirus while cushioning financial instability and social interruption.
A cohort of scientists from nine countries made the claim in an EU-backed study published on Wednesday.
They based their results on data from 16 countries and simulated how different lockdown strategies would impact the spread of Covid-19.
The scientists modelled several scenarios on 16 countries, including Bangladesh, India, Pakistan, Afghanistan, Sri Lanka, Australia, Belgium, Chile, South Africa, and Mexico.
Dr Rajiv Chaudhary, a global health epidemiologist at the University of Cambridge and the report's lead author, said that following the "50-day lockdown, relaxation for 30 days" routine will help save jobs.
However, the authors presented three potential scenarios to back their claim.
The first scenario talks about taking no steps at all.
This would lead to 7.8 million deaths across the countries included in the analysis, scientists argued, and the duration of the epidemic would be almost 200 days in the majority of these nations.
The second scenario modelled a rolling cycle of 50-day "mitigation measures" followed by a 30-day period where those measures were relaxed.
Analysts defined "mitigation measures" as strategies that gradually cut the number of new infections, such as social distancing, hygiene rules, isolating individuals with the virus, school closures and restricting large public events. These measures did not include a total lockdown.
It proved effective for the first three months. But after the first relaxation period, the scientists found the number of patients requiring intensive care unit (ICU) care would exceed hospital capacities.
This would lead to 3.5 million deaths across the 16 countries used in the simulation, with the pandemic lasting around 12 months in high-income countries and at least 18 months in other nations.
The scientists also modelled a third scenario, which involved a rolling cycle of stricter "suppression measures" for 50 days followed by a 30-day relaxation period.
"Suppression measures" were defined as those that led to a faster reduction in the number of new infections, achieved by applying strict lockdown measures on top of other mitigation measures.
"Our models predict that dynamic cycles of 50-day suppression followed by a 30-day relaxation are effective at lowering the number of deaths significantly for all countries throughout the 18-month period," Dr Rajiv Chowdhury said in a statement.
The scientists noted this approach could keep the number of patients in ICU below the available capacity and not overwhelm the hospital system.
The pandemic would result in a longer event, "beyond 18 months in all countries," but the number of people who would die across the 16 countries modelled would be just over 130,000.
"This intermittent combination of strict social distancing, and a relatively relaxed period, with efficient testing, case isolation, contact tracing and shielding the vulnerable, may allow populations and their national economies to 'breathe' at intervals – a potential that might make this solution more sustainable, especially in resource-poor regions," Dr Rajiv added.
Despite the outcome of the study, the scientists conceded these rolling lockdowns may not be best suited for every country and is just one option to be considered by lawmakers and public health officials.
They noted that individual countries would need to define for themselves how long the duration of the intervals would last to suit their domestic needs and facilities.
Oscar Franco, director of the Institute of Social and Preventive Medicine at the University of Bern in Switzerland, added that the research provided a strategic option for countries to better control Covid-19.
"There's no simple answer to the question of which strategy to choose," he said.
"Countries – particularly low-income countries – will have to weigh up the dilemma of preventing Covid-19 related deaths and public health system failure with the long-term economic collapse and hardship."
A continuous, three-month strategy of strict suppression measures would be the fastest way to end the pandemic, with most countries able to reduce new cases to near zero in this scenario, the scientists said.
Meanwhile, if looser mitigation strategies were continuously applied, it would take just over six months for new cases to fall close to zero, they concluded.