Five nurses from Frankston Hospital are believed to be in self-imposed home quarantine after it was discovered the cruise ship on which they were holidaying was carrying several passengers with human swine flu.

Peninsula Health chief executive Sherene Devanesen said "a small number of people" had been tested for the H1N1 influenza virus at Frankston Hospital but none had tested positive.

The nurses were on the P&O cruise ship Pacific Dawn, which allowed about 2000 passengers to disembark in Sydney last week, despite 172 of them indicating they had flu-like symptoms or had been in

contact with someone who did.

At least five passengers from the cruise ship and three crew members subsequently tested positive for the swine flu virus.

The Mail understands the nurses have not got swine flu, but have undertaken voluntary home 'quarantine' to eliminate any risk to the community. It is believed they will return to work this week.

Dr Devanesen said health services were "well prepared to respond to any cases of swine flu".

Frankston and Rosebud hospitals had "detailed response plans" that could be activated at a moment's notice.

"The plans include being able to administer the appropriate medication quickly and the establishment of special testing and treatment clinics if these become necessary."

She said Peninsula Health had sufficient stock of antiviral medication and was able to draw on State Government supplies if necessary.

None of the seven dedicated flu clinics that opened in Melbourne on Friday are in Frankston or on the Mornington Peninsula. The closest is at Dandenong Hospital.

Dr Devanesen said anyone with flu-like symptoms should consult a doctor, who would then refer them to Frankston or Rosebud hospital if necessary.

"Our hospitals and our community GPs are doing a wonderful job responding to concerns from the community."

Not everyone with flu symptoms would be tested for the H1N1 virus and test results were available within 8-12 hours.