(CNN) -- The Majestic Princess cruise ship was about halfway through a 12-day voyage when an outbreak of cases was noticed, Carnival Australia president Marguerite Fitzgerald told reporters in a media briefing on Saturday.
The ship had 4,600 passengers and crew on board at the time, according to CNN affiliate Nine News.
After mass testing 3,300 passengers, around 800 tested positive for COVID-19, as did a small number of crew, Fitzgerald said.
"All positive cases were mildly symptomatic or asymptomatic, and those guests isolated in their staterooms and then separated from non-impacted guests," parent company Princess Cruises representative Briana Latter told CNN.
Cruise operators separately escorted those infected off the ship and advised them to complete a five-day isolation period, CNN affiliate Nine News reported.
Those who tested negative were permitted to leave the ship, a New South Wales Health statement read.
"Carnival has advised NSW Health that they are assisting passengers with COVID-19 to make safe onward travel arrangements," the statement added.
Latter said the outbreak aboard the Majestic Princess was "reflective of an increase in community transmission in Australia."
Australia has seen an uptick in COVID cases recently, leading to more caution from within the government.
The New South Wales Ministry of Health has recorded 19,800 new cases of COVID-19 and 22 deaths in the past week.
The Majestic Princess cruise ship has since departed Sydney on her next voyage to Melbourne and Tasmania.
In a later statement, Fitzgerald said Carnival Australia have made over 50 international and domestic voyages "with a vast majority of more than 100,000 guests unimpacted by COVID." "However, the emergence of COVID in the community has meant we have seen a rise in positive cases on the last three voyages," she said.
Fitzgerald said the company has been implementing "the most rigorous and strict measures which go well above current guidelines", including requiring 95% of guests over the age of 12 to be vaccinated and testing staff and passengers for COVID before they board.
"We take our responsibility to keep everyone safe very seriously. This extends to not only caring for our guests, but also for the wider community in which we operate and visit," Fitzgerald said.
The Majestic Princess isn't the first Carnival cruise to be hit by a COVID outbreak.
At least three other ships within the company's Princess fleet -- the Ruby Princess, Diamond Princess, and Grand Princess -- experienced outbreaks earlier in the pandemic.