Maritime health: a case for preventing influenza on the high seas.

For decades cruise ships have been recognized as foci for diarrheal illness. More recently influenza has been added to the list of diseases for which people on cruise ships are at risk. Influenza is a business risk involving cruise ship operating and litigation costs and travelers' loss in value. Immunizing the crews could be one way to prevent introduction and spread of influenza on cruise ships. A cost-effectiveness analysis for vaccination of crews on cruise ships was conducted showing that it is not only cost-effective but it is cost savings.