Passenger ships carry a large number of people in confined spaces. A case of the new influenza A (H1N1) virus aboard a passenger ship is an expected event and would lead to rapid spread of the virus, if preventive measures are not in place. However, many cruise lines have detailed policies and procedures to deal with cases of influenza like illness (ILI). The EU SHIPSAN and SHIPSAN TRAINET projects include in their objectives guidelines for the prevention and control of communicable diseases aboard passenger ships. A literature review showed that from 1997 to 2005, nine confirmed outbreaks of influenza were linked to passenger ships, with attack rates up to 37%. It is important to establish and maintain a surveillance system for ILI aboard passenger ships, in order to systematically collect data that can help to determine the baseline illness levels. Monitoring these will enable early identification of outbreaks and allow timely implementation of control measures.
Mouchtouri, V., Black, N., Nichols, G., Paux, T., Riemer, T., Rjabinina, J., … Hadjichristodoulou, C. (2009). Preparedness for the prevention and control of influenza outbreaks on passenger ships in the EU: the SHIPSAN TRAINET project communication. Euro Surveillance : Bulletin Européen Sur Les Maladies Transmissibles = European Communicable Disease Bulletin, 14(21). https://doi.org/10.2807/ese.14.21.19219-en