Isolation of Legionella anisa from a hospital hot water system

Area of Science:

• Microbiology
• Infectious Diseases
• Environmental Health

Background:

• Legionnaires' disease outbreaks necessitate identifying causative agents.
• Hospital water systems are potential reservoirs for pathogenic bacteria.
• Legionella species identification is crucial for public health interventions.

Purpose of the Study:

• To identify the etiological agent of Legionnaires' disease cases in a French hospital.
• To characterize unusual legionella-like organisms isolated from the hospital's hot water system.
• To determine the taxonomic and pathogenic relationship of these isolates.

Main Methods:

• Isolation and characterization of legionella-like organisms from hospital water samples.
• Comparison of isolate characteristics with known Legionella species, including Legionella anisa and Legionella bozemanii.
• Assessment of potential pathogenicity and serological relationships.

Main Results:

• Thirteen strains of a legionella-like organism were isolated.
• These strains exhibited unusual characteristics, matching the description of Legionella anisa.
• The isolates were found to be identical to Legionella anisa, a species recently described by the CDC.

Conclusions:

• The identified Legionella anisa strains may be linked to the hospital-acquired Legionnaires' disease cases.
• Further investigation is needed to confirm the pathogenicity of these strains in humans.
• The relationship between these Legionella anisa strains and Legionella bozemanii serogroup 2 requires further study.