Travel-associated Legionnaires disease in Europe in 2009

Area of Science:

• Epidemiology
• Infectious Diseases
• Public Health Surveillance

Background:

• Legionnaires' disease (LD) is a severe respiratory infection caused by Legionella bacteria.
• Travel-associated LD (TALD) poses a significant public health concern, requiring robust surveillance systems.
• The European Surveillance Scheme for Travel-Associated Legionnaires' Disease (EWGLINET) monitors TALD cases across Europe.

Purpose of the Study:

• To report and analyze TALD cases in 2009 within the EWGLINET framework.
• To identify trends, geographical distribution, and risk factors associated with TALD.
• To assess the effectiveness of the surveillance scheme in detecting and managing outbreaks.

Main Methods:

• Data collection through EWGLINET from participating European and non-European countries.
• Analysis of case demographics, symptom onset, travel history, country of infection, and outcomes.
• Identification and investigation of TALD clusters and associated environmental factors.

Main Results:

• In 2009, 818 TALD cases were reported, a decrease from previous years.
• The United Kingdom and Italy reported the highest number of resident cases and infection cases, respectively.
• Eighty-eight new clusters were detected, with environmental samples testing positive for Legionella in 49 sites.

Conclusions:

• EWGLINET effectively identified TALD cases and clusters, with a significant proportion of clusters missed without the international database.
• Environmental contamination remains a key factor in TALD transmission.
• Continued surveillance and international collaboration are crucial for controlling travel-associated Legionnaires' disease.