The Swiss government banned gatherings of 1,000 people or more. Emerald City comic con, planned for this coming weekend in Seattle, was postponed. In New York City, Mayor Bill de Blasio asked people to work from home.

Evidence from past outbreaks shows that policies that keep people at a distance can prevent one from exploding. But cases of the virus in places that have n’t had a high number of cases identified.

During the 1918 influenza pandemic, fewer people died in cities that closed churches and schools early on. St. Louis, which closed movie theaters and canceled sporting events when only a few people had the flu, were able to reduce the spread of disease by around half.

Cases are spread out over a longer period of time, epidemiologists say. That prevents a sudden surge in the number of sick people. A flattened curve means there are n’t as many people sick at once.

There’s no consensus on the best time to put social distancing policies in place. It’s emotionally difficult for people to see everyday life disrupted around them. China locked down cities and kept people in their homes for weeks.

Some schools shut down, and some universities moved their classes online. Many companies are asking their employees to work from home. Some schools closed down and some schools moved online classes.

Many people do n’t have paid sick leave and ca n’t afford to stay home or off of crowded public transport if they’re feeling ill. New York City is reluctant to close all schools in response to the covid-19 outbreak because they’re the only places many kids get hot meals each day.