It’s no doubt tempting, in the face of a scary new virus, to shut borders and halt travel. With cases of the pneumonia-like Covid-19 illness topping 80,000 in dozens of countries, governments and companies are considering or have already implemented travel curbs. Yet the World Health Organization discourages “unnecessary restrictions of international traffic” as governments try to limit the spread of the disease.

1. What steps have been taken?

Travel restrictions have been imposed by more than 50 countries or territories in hopes of containing the virus, according to data compiled by the International Air Transport Association. The first and most dramatic was China sealing off the outbreak’s epicenter, Wuhan, a city of 11 million inhabitants, and the surrounding Hubei province. The U.S. has said it would bar entry of most foreigners who have been in China within the previous two weeks. Australia, Japan, Singapore, the Philippines and New Zealand also barred entry by non-citizens who had been in mainland China, and many airlines have suspended flights. Hong Kong, the international financial center that functions with some autonomy from China, announced restrictions as well. Even some mainland Chinese cities have begun to control arrivals from abroad.

2. Why would anyone object to such restrictions?

Consider Italy, which abruptly canceled flights to and from China when it emerged as an early European Union virus hot spot. The government’s decision was second-guessed, since travelers from China could still fly to other EU countries and enter Italy from there -- without a passport check -- depriving authorities of the ability to track arrivals or do spot medical checks at airports. And travel curbs can create a false sense of security, distracting countries from other crucual steps to fight an epidemic. Catherine Worsnop, an assistant professor in the School of Public Policy at the University of Maryland who has studied the effects of restrictions on people’s movement in past outbreaks, says such steps can merely delay an epidemic for a few weeks, at considerable economic and societal cost. Plus, the fear of trade and travel limits can lead governments to “intentionally conceal outbreaks to avoid economic and political harm,” Worsnop wrote in a 2019 study.

3. What does the WHO say?

The United Nations agency advises against restrictions on travel and trade to countries hit by the outbreak because costs -- social disruption and lots of resources -- usually outweigh benefits. Only in areas with few international connections and resources are temporary curbs useful, it says. Even during an outbreak last year of Ebola -- a far more deadly disease that kills about half of those infected -- the head of the WHO said any restrictions on travel or trade could hamper the fight rather than stop the spread, because such limits could lead people to use informal and unmonitored border crossings.

4. Is health screening at borders effective?

The WHO advised on Jan. 24 that departing travelers at China’s international airports and ports be screened for fever or other signs of coronavirus “while minimizing interference with international traffic.” As for how other countries deal with incoming passengers, the WHO said, “The evidence from the past outbreaks shows that effectiveness of entry screening is uncertain.” A big reason is that temperature monitoring may miss infected passengers still in the incubation phase and asymptomatic, or those trying to hide a fever. People suffering from other illnesses could also get caught up in the process.

5. So what should be done?

Instead of restrictions on travel, the WHO advises people stay put if they have a fever or cough and seek out medical attention early on if symptoms develop on the road. If people are returning from affected areas, they should remain isolated for 14 days. In the face of the virus’s rapid spread, governments are increasingly coming under fire by citizens looking for someone to blame. In South Korea, public fury is coalescing around the idea that authorities should have blocked Chinese from coming to the country sooner. Japanese Prime Minister Shinzo Abe has also been criticized for taking a softer approach to travel curbs on China, the country’s biggest trading partner.

6. What has this meant for the travel business?

Flight cancellations have skyrocketed since the virus’s outbreak. Most international carriers have announced plans to halt service to China. In a bid to reassure travelers, some airlines are turning to the world’s hardest-hitting disinfectants to rid planes of the coronavirus. Some cruise ships have found themselves all but trapped at sea over coronavirus concerns, as governments seek to keep cases away from their shores.

To contact the reporter on this story: Tara Patel in Paris at tpatel2@bloomberg.net

To contact the editors responsible for this story: Anthony Palazzo at apalazzo@bloomberg.net, Paul Geitner, John Lauerman

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