An Adelaide couple is among up to 2,000 people stuck on a cruise ship in the South China Sea after it was refused entry to the Philippines because of fears about the coronavirus.

Key points: The Westerdam cruise ship left Hong Kong for the Philippines on Saturday

The Westerdam cruise ship left Hong Kong for the Philippines on Saturday The Philippines banned incoming passengers from China because of coronavirus fears

The Philippines banned incoming passengers from China because of coronavirus fears The ship is in the South China Sea awaiting a decision on its next port of call

It comes as the South Australian Government announced 56 people have been tested for the coronavirus across the state.

Philippines President Rodrigo Duterte yesterday temporarily banned travellers from China, Hong Kong and Macau from disembarking in the country after it recorded the first death from coronavirus outside of China.

Holland America's cruise ship Westerdam left Hong Kong on Saturday after a six-hour stay, but about 24 hours into its trip to Manila the captain announced it would not be allowed into the Philippines.

David and Judy Holst were about halfway through a 30-day cruise through Asia, starting in Singapore and ending in Shanghai.

"My wife and I were at dinner and I said 'the boat's slowed down'," Mr Holst told ABC Radio Adelaide.

"It obviously was and then a little while later an announcement came over the PA saying Manila has denied us entry."

Hong Kong is not subject to the same strict travel restrictions as China.

The Westerdam cruise ship. ( Holland America )

Holland America announced in a blog post on January 28 it would still dock in Hong Kong for its February 1 cruise, but that the trip would finish in Yokohama, Japan, rather than Shanghai.

An undated update said cruises would no longer stop in Hong Kong from February 15.

Mr Holst said he was surprised when the Hong Kong stop-off to allow 800 more passengers on board went ahead.

The disability advocate described it as a "dumb, greedy decision".

"I couldn't believe that we were actually going to go there, but now the Philippines have implemented bans and we've had to do a U-turn," he said.

"Now we're in the South China Sea and I have no idea where we're going next."

Mr Holst said he asked guest services about the risks of stopping in Hong Kong but he was told to "be quiet and go away".

A photo of the South China Sea from the Westerdam cruise ship taken by David Holst. ( Facebook )

"'We're always working in your best interests' — that's what Holland America keeps telling us — and I'm certainly scratching my head on that one," he said.

Other passengers and crew appeared less worried about the Westerdam's course on Facebook.

"Westerdam just cancelled our first port stop in Manila due to coronavirus," American Bob Lapointe wrote.

"Now, tomorrow is another sea day… The poor crew that were supposed to get off and go home tomorrow can't!"

The Westerdam is scheduled to arrive in Kaohsiung, Taiwan, on Wednesday.

Holland America was contacted for comment.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 49 seconds 1 m 49 s PM announces measures to restrict coronavirus

SA authorities seek passengers on China Southern flight

Of the 56 people tested in South Australia, two tests have come back positive, 15 were negative and the rest are awaiting their results.

The couple with coronavirus — both aged 60 — travelled on China Southern flight CZ663 which landed in Adelaide on January 21.

"One of the cases was symptomatic on the flight," SA Health chief public officer Dr Nicola Spurrier said.

Anyone on board that flight is urged to contact health authorities.

Premier Steven Marshall said coronavirus can now be tested in the Royal Adelaide Hospital and is the fifth laboratory to be set up across Australia.

Meanwhile, a man on board a China Southern flight from Guangzhou to Adelaide that landed on Monday was reportedly suffering from a fever and had to be removed from the plane by specialist staff.

A China Southern Airlines flight at Adelaide Airport on Monday morning. ( ABC News: Helen Frost )

Ripley Callahan, who travelled on the flight, said someone felt "a bit ill".

"I don't know if it was related to the coronavirus at all," he said.

"He was taken off with his family and I suppose they were tested by some health professionals on the plane and assessed him and we just had to wait there.

"Health professionals wearing a green gown type of thing, masks and glasses."

Another passenger said she was sitting next to some of the man's family members and was concerned because she took off her mask to eat her meal.

"I was really, really worried," she said.

She said the man should not have got on the plane if he knew he was unwell.