Health professionals started the first screening for the deadly coronavirus with passengers from two flights from China that landed at Auckland Airport this morning.

The two flights are from Guangzhou and Shanghai, both cities have confirmed cases of the virus. The virus is thought to have originated in animals and has killed 56 people since it broke out in Wuhan, Hubei.

Cases have been confirmed in Japan, Taiwan, Nepal, Thailand, Vietnam, Singapore, Australia, the US, and France.

People from the two flights to land were wearing face masks as they came into the international arrivals hall. One woman, Jennifer, told RNZ people were wearing the masks while on the plane.

Director of Public Health Dr Caroline McElnay said the news that had come in overnight that coronavirus could infect people during incubation had yet to be reviewed.

"That's not something we have been informed about officially. My team are looking at what we have received and exactly what the facts are in terms of what's known about infectivity before symptoms. Yes it makes it much more challenging to contain and manage this virus. But we need to be really clear about what the facts are.