Cruise together and get sick together

The tragic death of Dianne Brimble aboard P & O’s Pacific Sky has focused attention on some of the risks associated with cruising.

This year more than 12 million people, including more than 200,000 Australians, will choose to embark on an ocean cruise. Cruise travel is booming like never before, it is a $50 billion industry, and the ships are getting bigger, the number of passengers travelling greater, the locations visited more exotic, and the range of activities and facilities ever expanding.

Cruising is seen as a relaxing, exciting and hassle-free way to go, offering the opportunity to visit many different places and cultures, even if only for a few hours.  The numbers cruising have almost doubled in the last six years and the size of cruise ships keeps creeping upwards.

The Explorer of the Seas now caters for more than 3,100 passengers and 1,200 crew. The newer cruise ships are floating mega hotels coming in at more than 138,000 tonnes, providing an extraordinary environment of decks, lifts, shopping arcades, restaurants, lounges, bars, cinemas, casinos, bingo halls and swimming pools, as well as generating vast amounts of waste and millions of litres of polluted water.

While some cruises have attracted an elderly clientele in various states of health, more middle-aged and young adults are also travelling, as well as young children. But just how safe is cruising? Are we more at risk on board a mega liner than walking in downtown Sydney?

Are passengers on “singles” cruises more at risk of sexual violence and sexually transmitted diseases, than they might be at home, and given that many of the crew are drawn from the developing world, are they at greater risk at harbouring infections such as TB and Hepatitis B? Is the fact that there have been 178 complaints of sexual assault and 34 deaths on cruises over the last few years something to worry about?

Well, evidence suggests that casual sex on cruise ships involves at least 10 per cent of all travellers and cruise-acquired STDs are probably fairly common, but in the context of 31 million passengers sailing on cruise ships over the last three years, the number of deaths and sexual assault claims seem very small.

Generally, medical problems aboard cruise ships largely mirror those of the wider community in that the most common diagnosis is respiratory illness followed by sprains and superficial wounds and minor contusions.

Recently, however, much attention has been focused on the increasing number of episodes of gastrointestinal illness on board cruise ships and there is evidence that the rate has increased substantially since 2001. Since 2004 there have been more than 80 incidents of contagious disease outbreaks on cruise ships involving almost 9,000 people.

Probably, this understates the true situation as many would suffer relatively minor illnesses in silence, particularly when access to the ship’s medical clinic is limited and needs to be paid for. In some cases substantial epidemics have raged, as on two large cruise ships in 2004 and 2005, when between 30 and 41 per cent of all passengers were swept up in major epidemics of gastroenteritis. Again, only a few months ago, one of the world’s super cruise liners saw 400 passengers fall ill with a severe gastrointestinal infection.

Cruises bring together people from a wide variety of contexts and backgrounds and sequester them in a small confined space, often sharing basic facilities with common food and water supplies, providing an environment within which respiratory and enteric infections can easily spread.

In addition, about one-third of all passengers are elderly and thus may be more susceptible to infectious disease. Crew members have also on occasions acted as reservoirs of infection, effectively transmitting infectious disease from cruise to cruise.

Overall, it would appear that the incidence of gastrointestinal infection is probably well below the level of “travellers diarrhoea” experienced by land-based tourists to developing countries but above that of the non-travelling Australian population.

One of the major problems facing the industry is that timelines between cruises are often very tight allowing little time for cleaning, proper end of voyage medical reports, and public health interventions. In addition, there is currently no international body which oversees healthcare or the practice of medicine on the high seas, and while some consensus-based healthcare guidelines do exist, their implementation largely rests with the particular cruise line and particular ships.

But don’t despair, cruise ships are probably as safe for your health as is the community in which you currently work and live - but just keep washing your hands!