Paul and Jacqui Fidrmuc will spend 12 more days in quarantine on the Diamond Princess moored off Yokohama as they anxiously await the results of their tests for the virus.

Twenty people - including two Australians - on the ship have already been confirmed as having coronavirus, as the rest of the 3700 passengers and crew wait to see if symptoms develop.

The Fidrmucs told AAP they are learning more from the media about the situation than they are from the cruise company.

They said their medical testing - which they passed - took only one minute and now it's just a matter of waiting for the quarantine period to pass.

"The concern we have is we might have the virus and we don't have the symptoms," Mr Fidrmuc said on Thursday.

"It's a frightening situation but it is not a disease where if you get it, it's certain death. You just have to be lighthearted about the whole situation."

Authorities say the Diamond Princess outbreak can be traced to an 80-year-old Hong Kong man who disembarked the ship last month.

Passengers are now forced to stay in their rooms for two weeks.

"We have heard recently they might let us out to walk around but that is only a rumour," Mr Fidrmuc said.

"We have all of the trimmings of a nice hotel room. We feel for those in interior rooms with no window."

Australian Associated Press