NSW health minister defends experts who handled Ruby Princess coronavirus outbreak

The New South Wales health minister, Brad Hazzard, has defended the role of health experts who allowed 2,700 passengers to disembark the Ruby Princess cruise ship and make their own way home, following reports that authorities knew about the widespread respiratory sickness on board.

As recriminations about the Ruby Princess saga continued on Saturday, the NSW police conducted the largest maritime operation in Sydney Harbour outside of wartime to move crew and supplies between a series of stranded cruise ships before they depart Australian waters.

NSW Health has confirmed it had been aware of 104 people with “acute respiratory infections” on the Ruby Princess before it docked in Sydney. Leaked emails show the ship’s doctor told authorities on 18 March that people who had presented at the onboard medical clinic with flu-like symptoms had tested negative for influenza.

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Yet on 19 March about 2,700 passengers were allowed to depart the ship at Sydney’s Circular Quay and travel onward, before test swabs had been analysed by state health authorities, who had considered the ship a “low risk” of carrying coronavirus.

A total of 662 people linked to the cruise ship have been infected with Covid-19 and seven passengers have died.

The NSW opposition leader, Jodi McKay, has described the incident as one of the most significant health failures in the state’s history and called on Hazzard to stand down.

During a heated press conference appearance on Saturday, the health minister faced aggressive questioning about the government’s handling of the Ruby Princess.

“Can I just say that the experts who made the decision were the best in the world,” Hazzard said.

“Each of the staff of the chief health officer who made the decision made it to the best of their ability. And those people are experts in their field.”

The NSW chief health officer, Dr Kerry Chant, said those who had died had all contracted the virus on board, and that authorities believed it might have spread through the ship from infected crew members preparing food. Sources familiar with ship said crew rarely disembarked and that the infection would have likely been brought on board by a passenger.

Chant said that if NSW Health had known that coronavirus was on board the ship, they would have disembarked the passengers differently and moved them directly to self-isolation.

But she said that would have only prevented 11 known cases of the virus that were subsequently spread within the community.

“Cases that we could have averted by decanting people in a more ordered way with face masks and taking them directly to their homes, would have been in the order of 11,” Chant said.

“The people that have acquired their infection on the cruise ship could not have been avoided and every period of time that people were on that cruise ship, there were actually at risk of more transmission on the cruise ship in a very, vulnerable age group.”

NSW Health has said the rapid influenza tests conducted onboard the Ruby Princess often return false negative results and that it believed “the illness and test results identified on board was consistent with influenza”.

Guardian Australia understands crew members on four Royal Caribbean ships – Celebrity Solstice, Ovation of the Seas, Voyager of the Seas and Spectrum of the Seas – are being sorted into groups according to their country of origin before the ships depart Australian waters.

NSW police said these ships would return to their home ports, though maritime sources say that is unlikely as most are “flag of convenience” vessels registered in the Bahamas. Crew members who remain onboard are mostly Indonesian, Indian, Sri Lankan and Filipino.

At least two of those ships – Voyager of the Seas and Celebrity Solstice – have been linked to fatal Covid-19 cases.

Documents seen by Guardian Australia show almost 800 crew members from Celebrity Solstice were transferred to two separate ships, the Ovation of the Seas and Voyager of the Seas, under police escort.

More than 600 crew members were transferred from the Ovation of the Seas to Spectrum of the Seas.

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Maritime sector sources told Guardian Australia many crew members stuck aboard those ships were “frightened” and believed they were being separated in order to be returned to their countries of origin.

Crew members have expressed concerns that the effect of the transfers will be to spread the contagion across several ships.

In a statement, NSW police marine area commander Steve Hegarty said the operation has been planned for several days.

“NSW Police has been instrumental in facilitating the movement of more than 750,000 tonnes of shipping through the Port of Sydney over about a 30-hour period,” he said.

“It will be the largest peacetime maritime operation undertaken in Sydney Harbour and has relied on the cooperation of Royal Caribbean cruise line and the Port Authority of NSW to ensure its success.”