Legionnaires' disease and the traveller

Area of Science:

• Infectious Diseases
• Epidemiology
• Microbiology

Background:

• A 1973 outbreak of respiratory illness affected a package tour group in Benidorm, Spain.
• Three tourists died from pneumonic illnesses, and 86 others staying at the same hotel reported respiratory symptoms.

Purpose of the Study:

• To investigate the cause of the 1973 Benidorm respiratory illness outbreak.
• To determine if the illness was linked to the bacterium later identified as the cause of Legionnaires' disease.

Main Methods:

• Sera from deceased and surviving tourists from the 1973 Benidorm outbreak were tested.
• Sera were analyzed for evidence of infection with the Legionnaires' disease bacterium.
• Antibody titers to the Legionnaires' disease bacterium were assessed in hotel staff.

Main Results:

• Evidence of Legionnaires' disease bacterium infection was found in three deceased tourists and two survivors.
• Six out of 16 hotel staff members showed elevated antibody titers, suggesting persistent or recurrent bacterial activity.
• The findings indicate a potential long-term presence of the Legionnaires' disease bacterium in the specific hotel or locality.

Conclusions:

• The 1973 Benidorm outbreak was retrospectively identified as an early instance of Legionnaires' disease.
• The study highlights the possibility of endemic Legionnaires' disease in specific locations.
• Ongoing research is necessary to quantify the contribution of Legionnaires' disease to traveler's illnesses.