Humidifier-associated paediatric Legionnaires' disease, Israel, February 2012

Abstract

We report a fatal case of community-acquired Legionnaires' disease in an infant aged under six months. Epidemiological and microbiological investigations suggested that a free-standing cold water humidifier using domestic tap water contaminated with Legionella pneumophila serogroup 1 served as a vehicle for infection. These findings were corroborated by sequence-based typing (SBT). Humidifier-associated Legionnaires' disease can be prevented by appropriate control measures. This case also illustrates the emerging role of SBT in the investigation of legionellosis.

Confirmed and Potential Sources of Legionella Reviewed

“…Room humidifiers were the subject of investigation in eight publications. In five studies, contaminated room humidifiers were associated with LD cases. − Three studies investigated Legionella contamination in humidifiers or aerosolization by humidifiers. − …”

“…Two source investigations involving infants exposed to room humidifiers filled with contaminated tap water were assigned the highest LOE (Ia). , Yiallouros et al reported a nosocomial outbreak, and Moran-Gilad et al described a community-acquired LD case. In both studies, a match was determined between the patient and environmental isolates by SBT.…”

A bioinformatics tool for ensuring the backwards compatibility of Legionella pneumophila typing in the genomic era

“…The sequence-based typing (SBT) scheme for L. pneumophila developed by the European Working Group for Legionella Infections (EWGLI, now European Society for Clinical Microbiology and Infectious Diseases (ESCMID) Study Group on Legionella Infections (ESGLI)) marked significant progress in the capacity for performing molecular epidemiology studies for LD [3,4]. This seven-locusbased scheme, conceptually and technically similar to multi-locus sequence typing (MLST) allows routine global surveillance and investigation of LD clusters, especially when adequate isolate metadata are available [5,6]. Nevertheless, the resolution of SBT may occasionally be limited and so more advanced typing approaches demonstrating an improved discriminatory index are needed.…”

Purification of living environments using photocatalysts: Inactivation of microorganisms and decomposition of allergens

“…Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel human coronavirus that has caused the COVID-19 pandemic, resulting in several deaths [ 59 , 90 ]. Additionally, the incidence of legionellosis, which can cause severe pneumonia, has increased worldwide [ 6 , 17 , 22 , 32 , 45 , 51 , 52 , 54 , 57 , 62 , 65 , 67 , 76 , 81 , 82 ]. Overcoming these infectious diseases is one of the most significant challenges of the 21st century.…”