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What’s Contact Tracing and How Can It Fight Covid-19?

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Contact Tracing and the Risk to Personal Privacy

When a forest fire is raging out of control, firefighters are forced to use blunt measures, such as trenches and aerial bombardment, to contain it. But they must also find and extinguish hidden hot spots to make sure the inferno doesn’t blaze up again. A pandemic isn’t entirely different. Broad lockdowns are a strategy for bringing the novel coronavirus under control. To stamp it out requires a technique that relies on old-fashioned shoe leather, thousands of workers and a high tolerance for boring details: contact tracing.

Not really, although some mobile phone technologies can help with it. (More on that later.) Contact tracing has been a major public-health tool since the U.S. and U.K. first used it against sexually-transmitted infections in the 1930s. It’s grunt work. Trained staffers ask infected people detailed questions about where they’ve been and who they’ve met. Everyone considered to be a contact -- a categorization that varies depending on how infectious the disease is -- is then informed and given guidance about what to do. In the case of Covid-19, close contact means living with someone who has the coronavirus or, according to one definition, having been in a closed environment within 2 meters (6.5 feet) of such a person for 15 minutes or more. These contacts are usually then advised to self-quarantine at home for 14 days while watching for symptoms.