A passenger onboard the novel coronavirus-hit cruise ship Diamond Princess says a lack of information on the duration of quarantine is causing uncertainty and hardship.

Photo: AFP

British couple Dave Abel and his wife were on the cruise when they were informed on Monday their vessel was being brought back to port at Yokohama a day early so 3700 passengers on board could be given health checks. The pair had been celebrating their 50th wedding anniversary onboard.

The decision to quarantine followed the diagnosis of an 80-year-old man with the deadly novel coronavirus after he disembarked in Hong Kong.

More than 60 passengers have now been diagnosed with the coronovirus, including one New Zealander.

Thirteen New Zealanders are onboard the ship, which had left Yokohama on 20 January. The ship had travelled through Japan, to Hong Kong, Vietnam and Taiwan before it was asked to return a day early to Yokohama.

All passengers had been confined to their cabins since Monday and only in the past 24 hours have passengers been allowed out on the deck for an hour-and-a-half each day.

Abel told Checkpoint the man who disembarked with the illness in Hong Kong had been onboard the ship for at least five days prior to disembarking.

Abel said he had been under the impression only 20 people had been stricken with the virus and that this inaccuracy was a reflection of a lack of adequate communication with the crew and passengers.

The couple had to cancel their flight home last Tuesday, and had paid for open tickets, but they still didn't know when they'd be able to fly home, or whether they'd be subject to another quarantine period when they arrived back.

"I've made a plea this morning, for the British Embassy, for the health officials in the UK to inform us. The information on board is very limited."

He said information was limited to safety protocols given to passengers, which involved limiting time spent outside their room, remaining one metre away from other passengers, not to congregate in groups and wearing face masks. They were told if a cough or fever was present to immediately inform staff.

The couple are now demanding to know when the quarantine period is going to end and when they will receive more health screening to enable them leaving.

"When is the quarantine going to end. Nobody can answer that question until we have all been health screened and we have not have any form of health since since getting into Yokohama last Monday," Abel said.

Authorities had previously advised crew and passengers would be quarantined for 14 days.

He said they had been treated well considering the circumstances and food had improved since Monday. However, a fellow elderly passenger with diabetes and a heart condition had been told by staff that they could not source some of his medicine, which he was bringing up with crew authorities.

"He is really concerned he's running out of medication. The captain announced all people running short of medication the ship would fill up prescriptions and supply them free of charge during this quarantine period. I don't know the reason why, but they can't fill his prescription."

Another passenger, US citizen Matthew Smith, said some people were experiencing in rougher than others.

"We've been a little more fortunate than our shipmates because we have a suite on the vessel giving us access to continually to the outside on our balcony... We sympathise with people stuck in inside cabins."

He said staff were supplying fresh towels and linen, but could not enter rooms and said there health officials onboard making sure measures were being adhered to and those sympathetic were looked at.