A Florida couple is seeking more than $1m from Princess Cruise Lines over potential exposure to the coronavirus aboard the Grand Princess.

The lawsuit, filed Monday in Los Angeles federal court by Ronald and Eva Weissberger, accuses Princess of negligence in allowing the 107,500-gt, 1998-built ship to sail 21 February despite outbreaks on it and the 115,900-gt Diamond Princess (built 2004).

"It would only stand to reason, that having experienced such a traumatic outbreak on board one of its vessels ... that the Defendant would have learned to take all necessary precautions to keep its passengers, crew and the general public safe," the complaint reads.

"Unfortunately, [Princess] did no such thing, which is why Plaintiffs are now at actual risk of immediate physical injury proximately caused by the Defendant's negligence."

The Diamond Princess was set to sail from San Francisco for Hawaii and Mexico last month. The 15-day voyage was cut short after two Princess passengers aboard a previous sailing had been infected with the respiratory illness, with one dying.

The ship was held offshore San Francisco for five days until Monday, when it was allowed to dock in Oakland. The lawsuit was filed when passengers were still being held on the ship, where the Weissbergers argue they suffered emotional distress and trauma.

The Grand Princess incident followed the long-term quarantine of the Diamond Princess in Japan, after 700 cases of the Covid-19 coronavirus were discovered aboard the ship, resulting in seven deaths.

According to the complaint, there were 62 passengers aboard the Grand Princess' 21 February sailing that were aboard the prior voyage. None of them, they allege, were tested until 5 March.

They said Princess screened passengers using a form where they were asked to confirm they were not sick.

Princess said it has been sensitive to the "difficulties" the virus has caused guests and crew and the response has been focused on their well-being before declining to comment on the lawsuit.

In the US, there are more than 700 confirmed cases of the coronavirus, with 26 deaths. Cases are clustered in Washington and New York states and California.

Globally, the World Health Organization counts more than 109,000 cases in 104 countries.

China remains the hardest hit with nearly 81,000 cases and more than 3,100 deaths. South Korea is the second most infected country with almost 7,400 cases.