Suppose the world had never instituted lockdowns in response to the pandemic: There’s a strong chance that 530 million more people would have gotten COVID-19.
That’s according to new research from the Global Policy Laboratory at the University of California, Berkeley. In a study published Monday, the lab examined the effects of more than 1,700 different lockdown measures across six countries: the US, China, South Korea, Italy, France, and Iran. The restrictions analyzed included travel bans, school closures, suspended religious services, event cancellations, and shelter-in-place orders.
Without any limits to people’s movement and interaction in the US, they found, the number of infections would have doubled every two days from March 3 to April 6. That means around 60 million more people could have been infected. (The US has so far reported 1.9 million cases.)
Lockdowns were even more successful in China, according to the study. The researchers found that policies implemented from January 16 to March 5 in China saved around 285 million people from getting sick. The nation has only reported around 84,000 cases thus far.
China’s earliest restrictions were implemented in Wuhan, where the outbreak originated. A March study found that Wuhan’s lockdown on January 23 prevented tens of thousands of infections throughout the Hubei province. Without the lockdown, cases in Hubei would have been 65% higher, the research showed.
Lockdown measures also prevented around 54 million infections in Iran, 49 million in Italy, 45 million in France, and 38 million in South Korea, according to the study.
“The deployment of anti-contagion policies in all six countries significantly and substantially slowed the pandemic,” the researchers wrote.
But they added that “seemingly small delays in policy deployment likely produced dramatically different health outcomes.”
In other words, nations like China benefitted from locking down early, while delays in the US and Italy may have resulted in unnecessary deaths. Indeed, disease modelers from Columbia University recently found that the US could have prevented 645,000 infections and 36,000 deaths by locking down one to two weeks earlier.
Europe’s lockdowns may have prevented more than 3 million deaths
Lockdowns also limited coronavirus-related hospitalizations and deaths in Europe. A team of researchers in Italy recently determined that the country’s lockdown prevented around 200,000 hospitalizations between February 21 (when Italy’s first case was reported) and March 25.
Another study from Imperial College London, published Monday, found that lockdown restrictions averted 3.1 million deaths across 11 European countries from the time these measures were implemented in March until May 4.
Italy avoided around 630,000 deaths during that period, according to the study. France, meanwhile, prevented around 690,000 deaths — the most out of the 11 countries.
While less than 1% of Germany’s population has contracted the virus, the nation averted around 560,000 deaths from March to May, according to the study. By contrast, Spain and the UK — where more than 5% of the population has been infected — managed to avert more than 400,000 deaths.
Nordic nations avoided the fewest deaths: around 34,000 in Denmark, 26,000 in Sweden, and 12,000 in Norway. About 3% of Sweden’s population is infected, compared to 1% in Denmark and less than 0.5% in Norway.
Overall, the researchers determined that lockdowns have a “large impact on transmission.” In all 11 countries, the current reproduction number (the number of other people one sick person infects, on average) was significantly below one. That means an average person with COVID-19 passes the virus to just one or fewer people — a sign that an outbreak is contained.
“We cannot say for certain that the current measures will continue to control the epidemic in Europe,” the researchers wrote. “However, if current trends continue, there is reason for optimism.”