Cent Eur J Public Health 2017, 25(3):235-239

Legionellosis: A Walk-Through to Identification of the Source of Infection

Dimosthenis Chochlakis^1,2, Vassilios Sandalakis^1,2, Maria Keramarou^1,2, Yannis Tselentis², Anna Psaroulaki^1,2

¹ Regional Laboratory of Public Health of Crete, Heraklion, Crete, Greece

² Laboratory of Clinical Bacteriology, Parasitology, Zoonoses and Geographical Medicine, University of Crete, Heraklion, Crete, Greece

Objectives: Although a number of human Legionnaires' disease in tourists are recorded annually in Europe, there are few cases where a direct link can be made between the infected person and the source of infection (hotel or other accommodation). We present a scheme followed in order to track down and identify the source of infection in a tourist suffering from L. pneumophila sg 5 infection, who was accommodated in seven different hotels during his holidays in the island of Crete, and we comment on various difficulties and draw-backs of the process.

Method: Water samples were collected from the seven hotels where the patient had resided and analyzed at the regional public health laboratory using cultivation and molecular tests.

Results: Of 103 water samples analyzed, 19 (18.4%) were positive for Legionella non-pneumophila and 8 (7.8%) were positive for L. pneumophila. A successful L. pneumophila sg 5 match was found between the clinical and environmental sample, which led us to the final identification of the liable hotel.

Conclusion: Timely notification of the case, within the the European Legionnaires' Disease Surveillance Network (ELDSNet) of the partners involved, is crucial during a course of travel associated with Legionella case investigation. Moreover, the urinary antigen test alone cannot provide sufficient information for the source identification. However, acquiring clinical as well as environmental isolates for serogroup and SBT identification is highly important for the successful matching.

Keywords: Legionella pneumophila sg 5, travel associated disease, surveillance, biotyping, urinary antigen test

Received: December 14, 2015; Revised: September 18, 2017; Published: October 10, 2017  Show citation