The message is getting out: #StayHome. In this early phase of the coronavirus pandemic, with undetected cases accelerating transmission even as testing ramps up, that is critical.

But there are many people whom the country needs to keep going into work—grocery cashiers, first responders, factory workers for critical businesses. Most obviously, we need health-care workers to care for the sick, even though their jobs carry the greatest risk of exposure.

How do we keep them seeing patients rather than becoming patients?

In the index outbreak in Wuhan, thirteen hundred health-care workers became infected; their likelihood of infection was more than three times as high as the general population. When they went back home to their families, they became prime vectors of transmission.

The city began to run out of doctors and nurses. Forty-two thousand more had to be brought in from elsewhere to treat the sick. Luckily, methods were found that protected all the new health-care workers: none—zero—were infected.

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