Does Contact Tracing Work? South Korea shows it does.

Does Contact Tracing Work? South Korea Proves It Does In May, when a coronavirus outbreak hit nightclubs in the South Korean capital of Seoul, health officials quickly unleashed their version of the Navy Seals -- elite teams of epidemiologists, database specialists and laboratory technicians. Heesu Lee Bloomberg.com

In May, when a coronavirus outbreak hit nightclubs in the South Korean capital of Seoul, health officials quickly unleashed their version of the Navy Seals -- elite teams of epidemiologists, database specialists and laboratory technicians.

An old-school, shoe-leather investigation showed the virus had jumped from a night-club visitor, to a student, to a taxi driver and then alarmingly to a warehouse employee who worked with 4,000 others.

Thousands of the employee’s co-workers, their family members and contacts were approached and 9,000 people were eventually tested. Two weeks later, the warehouse flareup was mostly extinguished and infections curtailed at 152.

The work of such so-called Immediate Response Teams offers a look at how South Korea -- once the second worst hit by the coronavirus -- has succeeded in largely quelling its spread without the lockdowns that have derailed lives worldwide. At a time when cities from Los Angeles to Melbourne to Tokyo are grappling with resurgences, South Korea’s playbook offers one of the most successful blueprints yet for containing a disease that’s killed more than 600,000 worldwide.

The tally of new cases in the Asian country -- which pioneered the testing blitz strategy -- has never fallen to zero, but the number of daily new cases have largely ranged from 30 to 60 for two months after peaking at more than 800 in February. Compare that with Los Angeles county, which added 2,014 cases on Thursday alone.

South Korea’s strategy is also a contrast with the harsh shutdowns instituted in parts of China or the tourism blockade implemented by New Zealand in an attempt to completely stamp out the virus. The Asian nation meticulously targets dangerous hotspots and then simply allows most people to lead lives and run businesses unimpeded.