Marilyn Halladay's love of cruising is infectious.

The Queenslander has been on 29 voyages and cannot wait for number 30.

That is despite the last journey — aboard the Diamond Princess — landing her in a Japanese hospital after catching COVID-19 from one of her fellow passengers.

"[I'm] ready to cruise again!" she told 7.30 this week.

"I just love the ship life."

The Diamond Princess was the earliest major cruise outbreak, and Marilyn was one of the first Australians infected with COVID-19.

With husband Ian, they were on a bus tour through the Japanese city of Kagoshima earlier in the trip with an infected passenger.

She spent 22 days in a Tokyo hospital, and now lives with some bizarre side-effects.

"I have strange feelings in my feet, I lost my sense of taste and smell ... I have a nose drip now," she said.

"I have had high blood pressure for many years, and my blood pressure is now lower than it's ever been."

The pair has nothing but praise for operator, Princess Cruises, and 77-year-old Marilyn is itching to set sail once more.

"With my failing mobility, it's the ideal thing for me, because I'm a bit past walking through cobblestone streets and uneven ground," she said.

"I can still enjoy the company of other people, seeing great places, and with modified mobility, I can tackle most things.

"Age is certainly against us. But that's why I'm keen."

'They're virtually begging us to come'

More than 700 Diamond Princess passengers and crew caught the virus, including 13 who died.

Ian Halladay dodged the disease, but is less keen on being around "a lot of people moving around in a confined space" out at sea.

"We get emails every day from them offering us great prices, great deals, free internet, free drinks, free anything; they're virtually begging us to come and cruise with them," he said.

"[But] I'm a bit reluctant to do anything at this stage."

Lessons learned from the Ruby Princess

The experience of the Diamond Princess — which became the largest virus outbreak outside China while docked at Yokohama — was not enough to prevent disaster the following month in Australia.

One year ago today, the Ruby Princess docked at Circular Quay in Sydney.

It had incubated the virus during its 11-day voyage to New Zealand and back.

NSW Health allowed passengers — including people later found to have COVID — to disembark and then scatter across the world.

In his first interview since leading the state's special commission of inquiry into the Ruby Princess, Bret Walker SC said he felt "shock" at some evidence he heard.

"[There were] slips and errors that really shouldn't have occurred," Mr Walker told the ABC's 7.30 program.

His other lasting memory relates to the way the federal and state governments handled the sick international arrivals.

"Everyone would have thought … that the system would be neatly worked out, effectively administered and incapable of producing problems," he said.

"Well, people would have been wrong on every count."

Four of his recommendations related to the federal agriculture authorities, and some require cooperation between state and federal governments — recommendations Mr Walker fears will take too long to implement.

"I've done … other work in the field of Commonwealth-state relations, and it's not a pretty sight, believe me," he said.

"Far too often, it's depressingly not very good."

The NSW Health department said it had "implemented all the recommendations relevant to NSW" from the special commission.

The Department of Agriculture, Water and the Environment, which has responsibility over biosecurity, also said in a statement: "Work is currently underway to implement all of the ... relevant recommendations."

The future of cruising

The Federal Government's ban on international cruising was recently extended until mid-June.

When voyages resume, Ruby Princess survivor Tony Londero wants an end to exorbitant medical costs on board voyages.

"I would personally like to see it included in the fare ... so it's easy for people to go to the medical centre and find out whether they've got something infectious, so they can contain that and stop it spreading through the ship," he told 7.30.

Mr Londero spent much of last March's fateful voyage in the ship's medical centre, suspected of having a minor heart attack but diagnosed with COVID-19 after being rushed to hospital.

His $8,000 onboard medical bill was covered by insurance, while Princess Cruises refunded him the insurance excess.

Researcher Ashley Quigley from the University of New South Wales' Kirby Institute said onboard COVID-19 testing facilities need to be available when cruising resumes to ensure a "rapid response to any situation that unfolds, and to ensure that the correct measures can be taken if there is an outbreak on board".

Vaccination should also be mandatory for cruise passengers, she said.

Joel Katz from industry body Cruise Lines International Association said passengers would be required to produce a negative COVID test before boarding, when cruising resumed.

"The industry has developed a comprehensive set of COVID protocols," Mr Katz said.

"[This includes improving] the ventilation systems on the on the ship, social distancing, and also operating at reduced capacity in order to be able to comply with the with the social distancing rules."

The Ruby Princess is currently anchored off the Mexican coast, and its operator Carnival plans for it to operate in North America once cruising resumes.

NSW Police is expected to hand a brief of evidence about Ruby Princess deaths to the state coroner within months, with an inquest due to start later this year.