The gastro outbreak on Australia's east coast has hit a popular cruise ship.

A gastro outbreak along Australia’s east coast has also been detected on a cruise ship.

A Metro North Public Health Unit spokeswoman said there were “at least 91 cases of gastro” on board a ship that docked in Brisbane on Thursday morning.

“We have been advised that on-board testing has found norovirus to be the cause of the illness,” she said in a statement.

Princess Cruises confirmed the spread on board the Sun Princess in a statement on Thursday.

A spokesman said the first case of gastro was reported on day one of the cruise, which left from Brisbane.

“Consistent with current public health alerts that norovirus and influenza are widespread in the general community in NSW, Victoria and Queensland respectively, proactive and successful steps were taken on board Sun Princess to limit any spread of the illness,” he said.

The spokesman said the crew conducted a “deep cleansing” of the ship on Thursday ahead of its turnaround, resulting in a slight delay in its departure.

News of the outbreak came just hours after Queensland Health confirmed "two frail residents" at a Regis aged care facility in Brisbane had died.

A Regis spokeswoman said while one of the patients had gastro, it wasn't clear whether the second patient had also been suffering from the bug.

The spokeswoman said there was currently an "episode of gastroenteritis" at the facility, which had been around since late July.

The spokeswoman said the two deaths had occurred during that time.

"In neither case did the doctor report gastro as being the cause of death," she said on Thursday.

"Our immediate priority is for the safety and wellbeing of our residents, residents' families, our staff on-site and the community.

"We have implemented our infection control processes and are continuing to do everything we can to safeguard our residents at the site."

A similar facility in Wynnum suffered a gastro outbreak in June, which affected 15 residents. However, there were no deaths.

Queensland Health Minister Cameron Dick said it wasn't unusual for viral conditions to spread, particularly during winter.

"I'm always concerned with anyone who passes away in any facility," he said on Thursday.

"That's a very sad thing."

Mr Dick said the government was now working with its federal counterparts to investigate what led to the deaths.