New Zealand imposed a two-week travel ban on arrivals from and through China on Monday and also warns its citizens to leave China fast.
Australia, the United States and seven other countries including Fiji, Russia, Japan and Indonesia, have also imposed entry restrictions on people from China, in an effort to limit contagion of the coronavirus from its source in Wuhan.
New Zealand's Director-General of Health Dr Ashley Bloomfield said preparations for the evacuation were well under way.
"The flight can take up to 300 people. The latest information I have, somewhere between 60 and 70 New Zealanders had indicated they wanted to be on the flight. The balance will be made up of Samoan and Tongan nationals and also Australians who may want to come back on that flight.
"So we will make every seat available. I can't tell you exactly the number of crew, but it would be similar to what you'd expect on a flight for 300 people, and of course there will be the medical staff on board as well."
Australians aboard the aircraft would be picked up by their own government at the point of arrival in New Zealand.
Other passengers will be isolated for two weeks at a temporary quarantine centre at a military base in Whangaporoa before returning to their home country.
Passengers will be charged a nominal flat fee of about $US300 and must pass a health check first.