While Americans watch the number of the coronavirus cases in their home states and cities tick up, they have few—if any—details about where people are getting infected or what the risk of going to, say, their local grocery store might be. In South Korea, the situation is different: People receive detailed alerts via text message whenever someone in their neighborhood is newly diagnosed. The messages name the specific businesses that person had recently visited, and what travel route they took to get there.
This type of public disclosure, made possible by legislation passed after the South Korean MERS outbreak in 2015, allowed businesses that hadn’t seen infected customers or staff to stay open—preventing as severe an economic fallout from the pandemic as the U.S. experienced—and was more effective in reducing COVID-19 deaths than broad stay-at-home orders, according to a recent National Bureau of Economic Research working paper.
South Korea and the U.S. both identified their coronavirus outbreaks on January 13. As of May 22, South Korea’s total number of cases was 11,142. The U.S. had more than 1,570,000. South Korea’s prominent testing was one reason, but Munseob Lee, an assistant professor of economics at UC San Diego and co-author of this research, says he wanted to look more closely at the country’s innovative public disclosure practice.
Twice a day, local Korean authorities publish a list of confirmed cases along with where and how those people traveled in the last few days, based on GPS data and credit card transactions. “People see that information and then they can avoid going to high-risk neighborhoods,” Lee says. “Or, say I went there—maybe three days ago I was at the Starbucks in this specific neighborhood—then there’s a possibility I was also next to [the] infected person. So then if I have symptoms, I can get tested.”
Armed this information, people actually changed their behaviors, the researchers say. According to foot traffic and GPS data, South Koreans changed their commuting behavior in response to district-specific information, especially on weekends, and particularly for those over 60 years old. Researchers saw an 18% drop in weekend commuting for those under 60, and a 44% drop for those 60 and older, to downtown Seoul when the number of infected cases there peaked. In general, residents traveled to districts with known cases less compared to their behavior before the cases were publicized, even though there was no government-imposed lockdown. In the U.S., where states had varying stay-at-home orders, people struggled to follow those orders or social distance while out, like when grocery shopping, according to reports. One analytical tool from the University of Maryland estimated that on average, a government stay-at-home order resulted in “just a 4.3% change in behavior.”
“Under the full lockdown . . . there are certain people who cannot work from home, and there are certain people with low health risk who may still want to go out,” Lee says. “Under the Korean strategy, the people could still go to the low-risk neighborhoods, and people with high health risk, say the elderly population or the vulnerable population, could decide to stay at home. That kind of selective or targeted social isolation was possible.”
The UC San Diego researchers modeled three different scenarios—no changes to behavior, a partial shutdown, and a lockdown—and compared that to public disclosure system in Seoul. Compared to the scenario with no behavior changes, public disclosure reduced the number of COVID-19 cases by 400,000 and deaths by 13,000 in the city of Seoul over two years.
Under the lockdown model, those under 60 saw a hit to their economic welfare, meaning their standard of living and general prosperity, twice as large as they did under a full disclosure situation, from the severe limitations on their ability to work and travel. “Compared to lockdown, this strategy of public disclosure saves more lives at a lower [economic] cost,” says Lee. The partial shutdown scenario was still economically costly and also the least effective in curbing cases, per the research.
There are, of course, privacy concerns. This information that South Korea’s system is based on comes from contracts between the government and the private companies that collect credit card transaction and GPS data. Though names of COVID-19 patients aren’t disclosed, there are still concerns both with the government having this information, and what this information may expose.
Researchers didn’t measure the cost of that infringement upon people’s privacy, but they say that that loss of privacy has to be measured against the benefits to public health. Months into this pandemic, Lee says, “people are experiencing and feeling the cost of the full lockdown. That’s why there’s a huge demand for reopening the businesses and economy.” In the wake of the first reopenings, though, more than a dozen states have seen record highs of new COVID-19 cases, and health experts warned early on about a possible second wave.
“What I’m recommending to the U.S. is now seriously discussing this possibility [of public disclosure,] because the social agreement for surveillance is needed,” he says, though he notes this has to go hand in hand with more testing, To Lee, we need to find a balance between public health and privacy. The U.S. couldn’t implement a national public disclosure practice immediately anyway, because it requires new legislation and legal and tech infrastructure such as new agreements between private companies and government. But, he says, “We can think about applying the Korean strategy to a smaller scale, at a city or company or university.”