Countries slamming borders shut as coronavirus spreads has caused travel chaos and the World Health Organization's Margaret Harris believes they should remain open but with thorough screening.

Harris has attempted to answer people's concerns over COVID-19 in a question and answer session. 

With lockdowns and social distancing, people have been told they should only travel when it is absolutely necessary. It has meant that movement has been restricted and borders between countries have been closed.

Many people who live abroad or depend on international travel for their livelihoods are worried over how long this will last and whether it is in fact necessary to block borders.

One expat living in New York put that question to Harris, who said it was important to keep borders open during a pandemic – especially to allow in equipment and supplies.

"If you have an ongoing infection, big outbreaks, you have to look at exit screening," she said. "You have to do your best to ensure that people infected don't leave your country. Countries at high risk, we advise them to do entry screening, ensure that you test – or as many countries are now doing, asking people to quarantine for 14 days. If there is any suggestion that someone may be bringing the virus in their body you find it early and you stop any ongoing transmission.

"At the moment countries are dealing with it by shutting borders, we prefer to see borders open but (with) those restrictions I've said before."

Harris explained that the problem with closing borders is that it hampers legitimate attempts to fight the outbreak. "If you close borders, you stop all travel," she said. "It means the help countries need – like logistics, the tests, the personal protective equipment, the experts you want... that limits the movement."

Harris was also asked what will be done to ensure that COVID-19 will not just come back once social distancing has stopped. 

"Wuhan is a good example, if you watch what is going in China," said Harris.

"They are doing it slowly: there is concern there could be some reseeding of their outbreak from people into the community. It is something that has to be done slowly and carefully but certainly something everyone is thinking very hard about now."

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