Sydney to treat cruise ships as potential flu sites

All cruise liners docking in Sydney will be treated as potential swine flu sites and passengers will be held on board until the ship is cleared under tough new measures launched yesterday.

The protocols were tightened after authorities came under fire for allowing 2,000 passengers off the Pacific Dawn to voluntarily self-quarantine in the community, despite a suspected outbreak of swine flu on board.

A total of 20 passengers have since been diagnosed with the virus, with another three suspected cases among a fresh group of guests on board the ship, which is currently headed to the Great Barrier Reef.

All the ship's crew had been given a course of anti-viral drugs and Health Minister Nicola Roxon said there would be a "significant increase in the number of cases that are confirmed, particularly in the coming days".

Prime Minister Kevin Rudd urged anyone suffering flu-like symptoms to seek the advice of a health professional, and called for vigilance on personal hygiene.

As the number of confirmed cases hit 66, authorities in New South Wales State said they would ramp up their response to cruise ships docking in Sydney.

"We will be treating all cruise ships as if they had swine flu on board and taking appropriate responses," said state chief health officer Kerry Chant.

"(This includes) not letting people off the ship until we have absolutely cleared swine flu being on it," Mr Chant said.

Ms Roxon said she expected a "dramatic increase" in the number of confirmed cases in the next two days, and said Australia faced some unique challenges in tackling the virus during the southern hemisphere's winter.

"We are coming into our flu season here in Australia while the northern hemisphere is moving out of their flu season, and no one is entirely sure what consequences that will have for the potential of those two flus to combine," Ms Roxon said.

Six schools were closed and a McDonald's fast food restaurant was shut down for 24 hours in Melbourne after a teenaged employee was diagnosed with the illness.

The virus also hit the popular National Rugby League code, with four referees in quarantine after sharing a flight with an infected passenger, the sport's officials said.