Broth microdilution protocol for determining antimicrobial susceptibility of Legionella pneumophila to clinically relevant antimicrobials.

Currently there is no detailed, internationally agreed protocol defined to evaluate antimicrobial susceptibility testing (AST) for Legionella pneumophila (required to establish epidemiological cut-off value or "ECOFF" boundaries); therefore, antimicrobial resistance in these isolates cannot be defined. AST methods utilising media containing activated charcoal as an ingredient, to enable Legionella growth, are unreliable as noted in an internationally authored opinion paper and a new gold standard is required. Here we define a detailed protocol for broth microdilution (BMD) using defined cell culture collection-deposited control reference strains (Philadelphia-1 and Knoxville-1) as well as two accessible reference strains with moderately (lpeAB-carrying) and markedly (23S rRNA mutation-carrying) elevated azithromycin minimum inhibitory concentration (MIC).

Legionnaires' disease in Switzerland: rationale and study protocol of a prospective national case-control and molecular source attribution study (SwissLEGIO).

Switzerland has one of the highest annual Legionnaires' disease (LD) notification rates in Europe (7.8 cases/100,000 population in 2021). The main sources of infection and the cause for this high rate remain largely unknown.

Resistance to ceftazidime-avibactam in a KPC-2-producing Klebsiella pneumoniae caused by the extended-spectrum beta-lactamase VEB-25.

Carbapenem-resistant Enterobacterales, including KPC-producing Klebsiella pneumoniae, represent a major threat to public health due to their rapid spread. The beta-lactam/beta-lactamase inhibitor (BL/BLI) combination ceftazidime-avibactam (CAZ-AVI) has recently been introduced and shown to exhibit excellent activity toward multidrug-resistant KPC-producing Enterobacterales strains. However, CAZ-AVI-resistant K.

Legionnaires' Disease: Update on Diagnosis and Treatment.

Legionellosis is the infection caused by bacteria of the genus Legionella, including a non-pneumonic influenza-like syndrome, and Legionnaires' disease is a more serious illness characterized by pneumonia. Legionellosis is becoming increasingly important as a public health problem throughout the world; although it is an underreported disease, studies have consistently documented a high incidence. In addition, health costs associated with the disease are high.

Whole-genome sequence-informed MALDI-TOF MS diagnostics reveal importance of Klebsiella oxytoca group in invasive infections: a retrospective clinical study.

Background: Klebsiella spp. are opportunistic pathogens which can cause severe infections, are often multi-drug resistant and are a common cause of hospital-acquired infections. Multiple new Klebsiella species have recently been described, yet their clinical impact and antibiotic resistance profiles are largely unknown.

Legionella antibiotic susceptibility testing: is it time for international standardization and evidence-based guidance?

Legionella pneumophila, a Gram-negative bacillus, is the causative agent of Legionnaire's disease, a form of severe community-acquired pneumonia. Infection can have high morbidity, with a high proportion of patients requiring ICU admission, and up to 10% mortality, which is exacerbated by the lack of efficacy of typical empirical antibiotic therapy against Legionella spp. The fastidious nature of the entire Legionellaceae family historically required inclusion of activated charcoal in the solid medium to remove growth inhibitors, which inherently interferes with accurate antimicrobial susceptibility determination, an acknowledged methodological shortfall, now rectified by a new solid medium that gives results comparable to those of microbroth dilution.

Legionnaires' Disease on the Rise in Switzerland: A Denominator-Based Analysis of National Diagnostic Data, 2007-2016.

The risk of falling ill with Legionnaires' disease (LD) is suggested to increase, but the global burden of disease is unknown due to a lack of appropriate diagnosis and surveillance systems. In Switzerland, the number of LD cases, captured by the National Notification System for Infectious Diseases, has more than doubled since 2008. This study aims to investigate this increase, contextualizing disease surveillance data with denominator data, which is not routinely available, i.

Air-conditioner cooling towers as complex reservoirs and continuous source of infection evidenced by a genomic analysis study in 2017, Switzerland.

IntroductionWater supply and air-conditioner cooling towers (ACCT) are potential sources of infection in people. During outbreaks, traditional typing methods cannot sufficiently segregate strains to reliably trace back transmissions to these artificial water systems. Moreover, because multiple strains may be present within these systems, methods to adequately distinguish strains are needed.

A community outbreak of Legionnaires' disease in Geneva, Switzerland, June to September 2017.

Purpose: Eight confirmed cases of Legionnaires’ disease were identified at the Geneva University Hospitals between 28 July 2017 and 02 August 2017, leading to a detailed outbreak investigation.

Methods: Legionnaires’ disease cases were defined according to Swiss and European (ELDSNet) consensus guidelines. An outbreak investigation task force was put in place.

Septic arthritis due to Legionella cincinnatiensis: case report and review of the literature.

Legionella spp. are an important cause of pulmonary and rarely extrapulmonary infections. L.

Comparison of Sofia Legionella FIA and BinaxNOW® Legionella urinary antigen card in two national reference centers.

The Sofia Legionella Fluorescence Immunoassay (FIA; Quidel) is a recently introduced rapid immunochromatographic diagnostic test for Legionnaires' disease using immunofluorescence technology designed to enhance its sensitivity. The aim of this study was to evaluate its performance for the detection of urinary antigens for Legionella pneumophila serogroup 1 in two National Reference Centers for Legionella. The sensitivity and specificity of the Sofia Legionella FIA test were determined in concentrated and nonconcentrated urine samples, before and after boiling, in comparison with the BinaxNOW® Legionella Urinary Antigen Card (UAC; Alere).

Influence of climate and geography on the occurrence of Legionella and amoebae in composting facilities.

Background: The incidence of Legionnaires' disease (LD) in southern Switzerland is three times higher than in northern Switzerland. Climatic and geographic factors may be potential causes for this difference.We studied the prevalence of Legionella and free-living amoebae (FLA) in compost and bioaerosol in two Swiss regions to understand the role of climate and geography in the transmission of LD.

ARDS with septic shock due to Legionella longbeachae pneumonia in a patient with polymyalgia rheumatica.

  Legionella longbeachae is a very uncommon cause of community acquired pneumonia in Western countries. L. longbeachae does not grow on blood agar media and is usually not detected by sputum gram stain or blood culture.

Phenotypic and genotypic identification of streptococci and related bacteria isolated from bovine intramammary infections.

Background: Streptococcus spp. and other Gram-positive, catalase-negative cocci (PNC) form a large group of microorganisms which can be found in the milk of cows with intramammary infection. The most frequently observed PNC mastitis pathogens (major pathogens) are Streptococcus uberis, Strep.

Presence of Legionella and free-living Amoebae in composts and bioaerosols from composting facilities.

Several species of Legionella cause Legionnaires' disease (LD). Infection may occur through inhalation of Legionella or amoebal vesicles. The reservoirs of Legionella are water, soil, potting soil and compost.

Meteorological factors and risk of community-acquired Legionnaires' disease in Switzerland: an epidemiological study.

Objectives: The aim of this study was to identify meteorological factors that could be associated with an increased risk of community-acquired Legionnaires' disease (LD) in two Swiss regions.

Design: Retrospective epidemiological study using discriminant analysis and multivariable Poisson regression.

Setting: We analysed legionellosis cases notified between January 2003 and December 2007 and we looked for a possible relationship between incidence rate and meteorological factors.

Molecular epidemiology of methicillin-resistant Staphylococcus aureus in Switzerland: sampling only invasive isolates does not allow a representative description of the local diversity of clones.

We conducted a molecular study of MRSA isolated in Swiss hospitals, including the first five consecutive isolates recovered from blood cultures and the first ten isolates recovered from other sites in newly identified carriers. Among 73 MRSA isolates, 44 different double locus sequence typing (DLST) types and 32 spa types were observed. Most isolates belonged to the NewYork/Japan, the UK-EMRSA-15, the South German and the Berlin clones.

Detection limits of Legionella pneumophila in environmental samples after co-culture with Acanthamoeba polyphaga.

Background: The efficiency of recovery and the detection limit of Legionella after co-culture with Acanthamoeba polyphaga are not known and so far no investigations have been carried out to determine the efficiency of the recovery of Legionella spp. by co-culture and compare it with that of conventional culturing methods. This study aimed to assess the detection limits of co-culture compared to culture for Legionella pneumophila in compost and air samples.

An international trial of quantitative PCR for monitoring Legionella in artificial water systems.

Aims:   To perform an international trial to derive alert and action levels for the use of quantitative PCR (qPCR) in the monitoring of Legionella to determine the effectiveness of control measures against legionellae.

Methods And Results:   Laboratories (7) participated from six countries. Legionellae were determined by culture and qPCR methods with comparable detection limits.

Rapid identification of Legionella spp. by MALDI-TOF MS based protein mass fingerprinting.

A set of reference strains representing 38 different Legionella species were submitted to Whole Cell Mass Spectrometry (WCMS) with MALDI-TOF. The dendrogram computed from strain mass spectral patterns obtained by WCMS was compared to the phylogenetic tree obtained from macrophage infectivity potentiator (mip) sequences. The trees inferred from these two methods revealed significant homologies.

Compost facilities as a reservoir of Legionella pneumophila and other Legionella species.

Data on the presence of Legionellae outside the aquatic environment are scarce. Alternative ecosystems that could act as a reservoir for Legionella spp. have been investigated to identify unconventional contaminated substrates that are able to produce bioaerosols.

Commercial potting soils as an alternative infection source of Legionella pneumophila and other Legionella species in Switzerland.

Legionella spp. are pathogens that can cause Legionnaires' disease in humans through inhalation of contaminated aerosols. The principal reservoir for these microorganisms is water, but Legionella spp.