Given the increase in the number of Legionnaires’ disease cases in recent years and the need for prompt and appropriate care, this disease represents a significant public health challenge.

Santé publique France is tasked with conducting epidemiological surveillance of this disease, supporting regional health agencies in investigating clusters of cases, and contributing to improving knowledge of the disease to better define new control and prevention strategies.

Epidemiological Surveillance of Legionellosis

Surveillance of Legionnaires' disease relies primarily on mandatory reporting and a network of partners. It is coordinated by Santé publique France.

Mandatory reporting

Mandatory reporting involves collecting as comprehensive information as possible regarding all cases of certain diseases known as “notifiable diseases” from laboratory technicians and physicians. It occurs in two successive stages: reporting and notification.

All cases of Legionnaires’ disease diagnosed by clinicians and laboratory professionals must be reported to the Regional Health Agencies (ARS), which validate the information, conduct an investigation with the patient or their contacts to identify risk exposures, search for other cases linked to these exposures, and implement, if necessary, control and prevention measures. The ARSs forward the reports to Santé publique France, which is responsible in particular for epidemiological surveillance at the national level.

Definition of reportable and notifiable cases of Legionnaires’ disease

A network of partners

Legionellosis surveillance relies on several partners:

• Regional Health Agencies (ARS)

The Regional Intervention Units (Cire) of Santé publique France work in collaboration with the Regional Health Agencies (ARS) to identify one or more common sources of contamination.

• The National Reference Center (CNR)

CNR for Legionella
Director: Prof. Sophie JARRAUD
Tel.: 04 72 07 16 38
Email: sophie.jarraud@chu-lyon.fr
Address:
Hospices Civils de Lyon Institute of Infectious Agents North Hospital Group - Microbiology Laboratory 103, Grande Rue de la Croix-Rousse - 69317 Lyon Cedex 04
Secretariat: 04 72 07 11 45 - Fax: 04 72 07 11 42 - Email: ghn_cnrlegionelles@chu-lyon.fr

• The Directorate General for Health (Ministry of Health)

The Ministry of Health provides on its website a resource package containing texts and practical information on the prevention and surveillance of Legionnaires’ disease. It is primarily intended for professionals responsible for the prevention, surveillance, and reporting of Legionnaires’ disease cases.

• The European Centre for Disease Prevention and Control (ECDC)

European Legionnaires’ Disease Surveillance Network (ELDSNet).
At the European level, the main objective is to identify clusters of cases that may be linked to a common source of exposure during travel, in order to take appropriate preventive measures.

The Legionnaires’ disease surveillance system is relatively comprehensive (comprehensiveness was estimated at 89% in 2010) and responsive (the majority of cases are reported within 10 days of symptom onset).

Preventive measures against Legionnaires’ disease

To support the professionals involved, the High Council for Public Health has developed a guide for investigating and managing one or more cases of Legionnaires' disease.
The Ministry of Health offers a page dedicated to the prevention of Legionnaires' disease, outlining the requirements by type of facility and establishment.