Better Health Surveillance on International Cruise Ships

Associate Professor Mark Ferson, Director of the South Eastern Sydney Public Health Unit South Eastern Sydney and Illawarra Area Health Service, reports that over the past decade, but particularly since 1998, staff at the South Eastern Sydney Public Health Unit (PHU) have worked with Sydney-based shipping lines operating international cruises to improve health surveillance on cruise ships.

"The number of people travelling on cruise ships is expected to reach 22 million by 2010," Professor Ferson said.

Conditions on cruise ships increase the chance of infection because of the presence of crew and passengers from many parts of the world, shared sanitation facilities and common food and drinking water supplies. The consumption of foods ashore, where food safety standards may be poor is another source of infection.

The semi-enclosed environment of the cruise ship also fosters rapid person-to-person infections such as the flu. Older passengers may also be more susceptible to infections and to complications arising from illness.

Since the development of the new health surveillance program, not only are quarantinable diseases reported, but also all infectious diseases of public health interest for every cruise.

From 1999-2003, the surveillance program detected and responded to 14 outbreaks of gastroenteritis or acute respiratory infection, affecting more than 1,400 passengers and crew.

Professor Ferson cites one example where on 8 June 1999, the Victorian Health Department reported typhoid in a 38-year-old man who had been ill since 30 May. As further cases were reported, it became evident that all had travelled on a Cairns to Sydney cruise, which had visited Papua New Guinea. Active follow up from a national outbreak investigation, confirmed 12 typhoid cases from a possible 19 cases.

"This investigation brought to attention the lack of awareness of the Quarantine Act requirement for ships' masters to report gastroenteritis. In addition, the cruise ship operator instigated recommendations for typhoid vaccination for travellers to Papua New Guinea," Associate Professor Ferson said.

The program has led to a better understanding of the need for ships' doctors and masters to report infectious diseases. Vessel operators are also advised to waive professional medical fees during an outbreak, encouraging more people to seek medical advice and enabling authorities to establish the real extent of the outbreak.

There are plans to negotiate with other operators of cruise ships using Sydney and other Australian ports to provide standardised end-of-voyage medical reports. A similar program has recently been initiated in Queensland, and discussions are underway towards a coordinated, national cruise ship surveillance program modelled on the Sydney program.

The Medical Journal of Australia is a publication of the Australian Medical Association.

CONTACT Associate Professor Mark FERSON 0401 141 890

Judith TOKLEY, AMA Public Affairs, 0408 824 306 / 02 6270 5471