Emergency health and safety measures taken in six major countries have prevented more than 500 million infections during the COVID-19 coronavirus pandemic, according to a study published Monday by researchers at the University of California, Berkeley.
The report, published in the journal “Nature,” is the first peer-reviewed analysis of local, regional and national coronavirus containment and prevention policies in China, South Korea, Italy, Iran, France and the United States.
The researchers estimate public health and safety measures like travel restrictions, business and school closures and shelter-in-place orders have prevented about 530 million infections between January and April 6, when the study ended.
“I don’t think any human endeavor has ever saved so many lives in such a short period of time,” said lead author Solomon Hsiang, the director of UC Berkeley’s Global Policy Laboratory. “There have been huge personal costs to staying home and canceling events, but the data show that each day made a profound difference.”
Researchers did not estimate the number of deaths prevented during that time because fatality rates in all six countries likely would’ve been even higher as the number of cases increased.
The study analyzed 1,717 policies implemented in the six countries, where the number of new infections grew an average of 38 percent each day before coronavirus prevention policies were put in place.
“So many have suffered tragic losses already,” Hsiang said. “And yet, April and May would have been even more devastating if we had done nothing, with a toll we probably can’t imagine.”
In the United States alone, the researchers estimated that coronavirus policies prevented some 4.8 million confirmed cases and 60 million total cases. Only China prevented more confirmed cases, 37 million, and total cases, 285 million, during the study’s time period.
The study found that self-isolation and business and economic lockdowns produced the largest benefits while other policies like travel restrictions did not produce clear case prevention benefits. Benefits of public health policy usually took about three weeks to appear.
According to the researchers, early preventative action in countries like Brazil, India and Mexico where cases are taking off could be the difference in preventing thousands of cases and deaths in the coming months.
“It’s as if the roof was about to fall in, but we caught it before it crushed everyone,” Hsiang said of the six countries’ timing. “It was difficult and exhausting, and we are still holding it up. But by coming together, we did something as a society that nobody could have done alone and which has never been done before.”
The study can be accessed at nature.com/articles/s41586-020-2404-8.