Royal Caribbean – and the rest of the cruise industry – will be studying closely the extraordinary case of an elderly passenger who tested positive while at sea, then twice tested negative onshore.

Singapore’s Ministry of Health said the 83-year-old Singaporean’s original sample was retested at the National Public Health Laboratory. A second fresh sample tested by the laboratory also came back negative.

A further test was due to be taken today.

Singapore Tourism Board director of cruise Ms Annie Chang told media outlets the man  reported to the on-board medical centre with diarrhoea, and took a mandatory PCR (polymerase chain reaction) test.

She said the man had already tested negative prior to boarding.

In an updated statement late yesterday, she said the passenger was taken to hospital for further testing, and the remaining 1,680 passengers and 1148 crew had to stay on board while contact tracing took place.

COVID positive Quantum of the Seas
Quantum COVID

They were released late last night, after waiting for the Genting World, which is also sailing cruises to nowhere, boarded its passengers.

 Royal Caribbean has now announced cancellation of its next four-night cruise, due to leave on Thursday.  The crew will be retested and the megaliner will be deep cleaned.

But the bigger question mark is over the efficacy of testing, and whether it can now be relied upon.

The cruises are part of a pilot program launched by Singapore Tourism Bopard, which has invested heavily in the cruise market and is keen to maintain its position as a cruise hub.  The three and four night cruises are part of an Ocean Gataway series or, as Genting Cruises calls them, Seacations.

Only Singaporeans are allowed on board and there are no ports of call. The cruise ships is designed as a “bubble”.

But tests have proved faulty in the past.

SeaDream cancelled all its cruises in the Caribbean after a guest who tested negative prior to boarding showed up positive during the cruise, and  nine people altogether tested positive. Uncruise Adventures also cancelled sailings in Alaska when a guest tested positive, but was then later confirmed to be a “false positive”.

Passengers reported the latest incident was handled well and in an orderly fashion.

Disembarked passengers have been told to monitor their health for two weeks.

The Straits Times quoted Mr Mah Chin Heng as saying he was glad he took the cruise, as his in-laws, who are in their 60s, celebrated their wedding anniversary.

“We were able to do all the activities we had planned for, such as rock climbing and watching the evening performance on board,” he told the paper.

Royal Caribbean had previously announced a generous compensation package and medical insurance for guests on the cruises.

Passengers who tested positive for COVID-19 and others travelling with them will get a full refund, and the rest of the guests will receive pro-rata refunds for the day missed at sea plus a day’s Future Cruise Credit.

Royal Caribbean has equipped its ships with full testing and medical facilities, including ventilators. Passengers must carry a tracing device and wear masks when necessary.

Genting Cruises World Dream’s has real-time PCR testing.

The question now is how accurate this testing is – and whether it can be improved.