Activation of class 1 integron integrase is promoted in the intestinal environment.

Class 1 integrons are widespread genetic elements playing a major role in the dissemination of antibiotic resistance. They allow bacteria to capture, express and exchange antibiotic resistance genes embedded within gene cassettes. Acquisition of gene cassettes is catalysed by the class 1 integron integrase, a site-specific recombinase playing a key role in the integron system. In in vitro planktonic culture, expression of intI1 is controlled by the SOS response, a regulatory network which mediates the repair of DNA damage caused by a wide range of bacterial stress, including antibiotics. However, in vitro experimental conditions are far from the real lifestyle of bacteria in natural environments such as the intestinal tract which is known to be a reservoir of integrons. In this study, we developed an in vivo model of intestinal colonization in gnotobiotic mice and used a recombination assay and quantitative real-time PCR, to investigate the induction of the SOS response and expression and activity of the class 1 integron integrase, IntI1. We found that the basal activity of IntI1 was higher in vivo than in vitro. In addition, we demonstrated that administration of a subinhibitory concentration of ciprofloxacin rapidly induced both the SOS response and intI1 expression that was correlated with an increase of the activity of IntI1. Our findings show that the gut is an environment in which the class 1 integron integrase is induced and active, and they highlight the potential role of integrons in the acquisition and/or expression of resistance genes in the gut, particularly during antibiotic therapy.

Emayella augustorita, New Member of Pasteurellaceae, Isolated from Blood Cultures of Septic Patient.

We report discovery of a new bacterial genus and species of the family Pasteurellaceae by using phylogenetic and metabolic analysis. The bacterium, Emayella augustorita, was isolated from blood cultures of a patient in France diagnosed with an adenocarcinoma of the intestines and who was treated with a biliary prosthesis placement.

Sedimentation field-flow fractionation for rapid phenotypic antimicrobial susceptibility testing: a pilot study.

BACKGROUND: The increase in antibiotic resistance is a major public health issue. The development of rapid antimicrobial susceptibility testing (AST) methods is becoming a priority to ensure early and appropriate antibiotic therapy. OBJECTIVES: To evaluate sedimentation field-flow fractionation (SdFFF) as a method for performing AST in less than 3 h. METHODS: SdFFF is based on the detection of early biophysical changes in bacteria, using a chromatographic-type technology. One hundred clinical Escherichia coli strains were studied. A calibrated bacterial suspension was incubated for 2 h at 37°C in the absence (untreated) or presence (treated) of five antibiotics used at EUCAST breakpoint concentrations. Bacterial suspensions were then injected into the SdFFF machine. For each E. coli isolate, retention times and elution profiles of antibiotic-treated bacteria were compared with retention times and elution profiles of untreated bacteria. Algorithms comparing retention times and elution profiles were used to determine if the strain was susceptible or resistant. Performance evaluation was done according to CLSI and the ISO standard 20776-2:2021 with broth microdilution used as the reference method. RESULTS: AST results from SdFFF were obtained in less than 3 h. SdFFF showed high categorical agreement (99.8%), sensitivity (99.5%) and specificity (100.0%) with broth microdilution. Results for each antimicrobial were also in agreement with the ISO 20776-2 recommendations, with sensitivity and specificity of ≥95.0%. CONCLUSIONS: This study showed that SdFFF can be used as a rapid, accurate and reliable phenotypic AST method with a turnaround time of less than 3 h.

Characterization of Pseudomonas aeruginosa resistance to ceftolozane-tazobactam due to ampC and/or ampD mutations observed during treatment using semi-mechanistic PKPD modeling.

A double ampC (AmpCG183D) and ampD (AmpDH157Y) genes mutations have been identified by whole genome sequencing in a Pseudomonas aeruginosa (PaS) that became resistant (PaR) in a patient treated by ceftolozane/tazobactam (C/T). To precisely characterize the respective contributions of these mutations on the decreased susceptibility to C/T and on the parallel increased susceptibility to imipenem (IMI), mutants were generated by homologous recombination in PAO1 reference strain (PAO1- AmpCG183D, PAO1-AmpDH157Y, PAO1-AmpCG183D/AmpDH157Y) and in PaR (PaR-AmpCPaS/AmpDPaS). Sequential time-kill curve experiments were conducted on all strains and analyzed by semi-mechanistic PKPD modeling. A PKPD model with adaptation successfully described the data, allowing discrimination between initial and time-related (adaptive resistance) effects of mutations. With PAO1 and mutant-derived strains, initial EC50 values increased by 1.4, 4.1, and 29-fold after AmpCG183D , AmpDH157Y and AmpCG183D/AmpDH157Y mutations, respectively. EC50 values were increased by 320, 12.4, and 55-fold at the end of the 2 nd experiment. EC50 of PAO1-AmpCG183D/AmpDH157Y was higher than that of single mutants at any time of the experiments. Within the PaR clinical background, reversal of AmpCG183D, and AmpDH157Y mutations led to an important decrease of EC50 value, from 80.5 mg/L to 6.77 mg/L for PaR and PaR-AmpCPaS/AmpDPaS, respectively. The effect of mutations on IMI susceptibility mainly showed that the AmpCG183D mutation prevented the emergence of adaptive resistance. The model successfully described the separate and combined effect of AmpCG183D and AmpDH157Y mutations against C/T and IMI, allowing discrimination and quantification of the initial and time-related effects of mutations. This method could be reproduced in clinical strains to decipher complex resistance mechanisms.

Sedimentation Field-Flow Fractionation: A Diagnostic Tool for Rapid Antimicrobial Susceptibility Testing.

Conventional antimicrobial susceptibility testing (AST) methods require 24-48 h to provide results, creating the need for a probabilistic antibiotic therapy that increases the risk of antibiotic resistance emergence. Consequently, the development of rapid AST methods has become a priority. Over the past decades, sedimentation field-flow fractionation (SdFFF) has demonstrated high sensitivity in early monitoring of induced biological events in eukaryotic cell populations. This proof-of-concept study aimed at investigating SdFFF for the rapid assessment of bacterial susceptibility to antibiotics. Three bacterial species were included (Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa) with two panels of antibiotics tailored to each bacterial species. The results demonstrate that SdFFF, when used in "Hyperlayer" elution mode, enables monitoring of antibiotic-induced morphological changes. The percentage variation of the retention factor (PΔR) was used to quantify the biological effect of antibiotics on bacteria with the establishment of a threshold value of 16.8% to differentiate susceptible and resistant strains. The results obtained with SdFFF were compared to that of the AST reference method, and a categorical agreement of 100% was observed. Overall, this study demonstrates the potential of SdFFF as a rapid method for the determination of antibiotic susceptibility or resistance since it is able to provide results within a shorter time frame than that needed for conventional methods (3-4 h vs 16-24 h, respectively), enabling earlier targeted antibiotic therapy. Further research and validation are necessary to establish the effectiveness and reliability of SdFFF in clinical settings.

Towards One Health surveillance of antibiotic resistance: characterisation and mapping of existing programmes in humans, animals, food and the environment in France, 2021.

BackgroundInternational organisations are calling for One Health approaches to tackle antimicrobial resistance. In France, getting an overview of the current surveillance system and its level of integration is difficult due to the diversity of surveillance programmes.AimThis study aimed to map and describe all French surveillance programmes for antibiotic resistance (ABR), antibiotic use (ABU) and antibiotic residues, in humans, animals, food and the environment, in 2021. Another objective was to identify integration points, gaps and overlaps in the system.MethodsWe reviewed the literature for surveillance programmes and their descriptions. To further characterise programmes found, semi-directed interviews were conducted with their coordinators.ResultsIn total 48 programmes in the human (n = 35), animal (n = 12), food (n = 3) and/or the environment (n = 1) sectors were identified; 35 programmes focused on ABR, 14 on ABU and two on antibiotic residues. Two programmes were cross-sectoral. Among the 35 ABR programmes, 23 collected bacterial isolates. Bacteria most targeted were Escherichia coli (n = 17 programmes), Klebsiella pneumoniae (n = 13), and Staphylococcus aureus (n = 12). Extended-spectrum beta-lactamase-producing E. coli was monitored by most ABR programmes (15 of 35) in humans, animals and food, and is a good candidate for integrated analyses. ABU indicators were highly variable. Areas poorly covered were the environmental sector, overseas territories, antibiotic-resistant-bacterial colonisation in humans and ABU in companion animals.ConclusionThe French surveillance system appears extensive but has gaps and is highly fragmented. We believe our mapping will interest policymakers and surveillance stakeholders. Our methodology may inspire other countries considering One Health surveillance of ABR.

Integron detection for prediction of trimethoprim/sulfamethoxazole susceptibility in children with Enterobacterales urinary tract infections.

OBJECTIVES: In some countries, third-generation cephalosporins (3GCs) serve as first-line therapy in children with urinary tract infections (UTIs). However, their use may contribute to the emergence of antibiotic resistance, notably among Gram-negative bacteria (GNB). Integrons are bacterial genetic elements involved in antibiotic resistance in GNB. Their absence is associated with >97% susceptibility to trimethoprim/sulfamethoxazole in adults infected with GNB. The objective of this study was to examine the value of integron detection directly from urine samples as a predictive marker of resistance to trimethoprim/sulfamethoxazole in children with GNB-related UTIs. METHODS: Children admitted to the Limoges University Hospital's paediatric emergency department between February 2018 and March 2019 with a suspicion of UTI were eligible for the study. Only confirmed cases presenting a positive urine culture with unique GNB were retained for further study analyses. Integrons were detected directly from urines using real-time PCR. RESULTS: The data of 72 patients were analysed and integrons were detected in 15 urine samples. The negative predictive value of integron detection for resistance to trimethoprim/sulfamethoxazole was 100% as all of the GNB (all were Enterobacterales) isolated from patients with no integrons detected in their urine samples were susceptible to trimethoprim/sulfamethoxazole. CONCLUSIONS: The detection of integrons in cases of paediatric patients with suspected UTI could help limit 3GC empirical use and empower an empirical first-line strategy better tailored to the needs of each patient.

Long-term neuro-functional disability in adult patients with community-acquired bacterial meningitis.

PURPOSE: To investigate the prevalence of neuro-functional disability and its determinants 12 months after community-acquired bacterial meningitis (CABM) in adult patients. METHODS: In a prospective multicenter cohort study (COMBAT), all consecutive cases of CABM were enrolled and followed up for 12 months. Neuro-functional disability at 12 months was evaluated using a combination of the Glasgow Outcome Scale (functional disability), and the modified Rankin Disability Scale (physical disability). Factors associated with neuro-functional disability were identified by multivariate logistic regression. RESULTS: Among 281 patients, 84 (29.9%) patients exhibited neuro-functional disability at 12 months: 79 (28.1%) with functional disability and 51 (18.1%) with physical disability. Overall, 6 patients (2.1%) died during the follow-up. The most common pathogen identified was Streptococcus pneumoniae (131/272, 48.2%); 77/268 patients (28.7%) had a physical disability at hospital discharge. Factors independently associated with 12-month neuro-functional disability were a pneumococcal meningitis (adjusted OR = 2.8; 95% confidence interval (CI) = [1.3; 6.7]), the presence of a physical disability at hospital discharge (aOR = 2.3; 95%CI = [1.2; 4.4]) and the presence of behavioral disorders at hospital-discharge (aOR = 5.9; 95%CI = [1.6; 28.4]). Dexamethasone use was not significantly associated with neuro-functional disability (OR = 0.2; 95%CI = [< 0.1;1.3]). CONCLUSION: Neuro-functional disability is frequently reported 12 months after CABM. Detailed neurological examination at discharge is needed to improve the follow-up. TRIAL REGISTRATION: NCT01730690.

Relationship between serotypes, disease characteristics and 30-day mortality in adults with invasive pneumococcal disease.

PURPOSE: Invasive pneumococcal disease (IPD) is responsible for substantial mortality and morbidity worldwide. We aimed to identify host and bacterial factors associated with 30-day mortality in 18-year-old patients hospitalized with IPD in France from 2013 to 2015. METHODS: This study analyzed data collected from consecutives IPD cases included in two parallel multi-center cohort studies: COMBAT study (280 patients with pneumococcal community-acquired bacterial meningitis) and SIIP study (491 patients with non-meningitis IPD). Factors associated with 30-day mortality were identified using logistic regression. RESULTS: Among the 771 enrolled patients (median age 66 years, IQR [52.0-79.7]), 592/767 (77.2%) had at least one chronic disease. Patients with meningitis were younger (60.2 vs 70.9 years; p < 0.001) and had fewer chronic diseases than those with non-meningitis IPD (73.3% vs 79.4%; p = 0.05). Non-vaccine serotypes were more frequent in meningitis patients than in those with other IPD (36.1% vs 23.1%; p < 0.001). The overall 30-day mortality was 16.7% and patients with concurrent meningitis and extra-cerebral IPD had the highest 30-day mortality rate (26.5%). On multivariate analyses, older age, history of malignant solid tumor, meningeal IPD and serotypes previously identified with high mortality potential were independently associated with 30-day mortality. Of the serotypes with high mortality potential, 80% were included in licensed (PCV13 or PPV23) vaccines. CONCLUSION: We observed an effect of both host factors and pneumococcal serotypes on 30-day mortality in IPD. This highlights the need for a focused strategy to vaccinate at-risk patients. CLINICAL TRIAL: ClinicalTrial. Gov identification number: NCT01730690.

Routine use of 16S rRNA PCR and subsequent sequencing from blood samples in septic shock: about two case reports of Capnocytophaga canimorsus infection in immunocompetent patients.

BACKGROUND: Capnocytophaga canimorsus infection happens frequently in immunosuppressed patients with reported domestic animal bites. Clinical presentation ranges from simple cellulitis to fulminant septic shock with disseminated intravascular coagulopathy, with an overall mortality of 30%. Conventional blood culture is often negative as this is a slow-growing pathogen. Nevertheless, the increasing use of 16S rRNA gene amplification and Sanger sequencing allows a much more rapid diagnostic confirmation. We present two case reports where 16S rRNA gene sequencing helped to diagnose Capnocytophaga canimorsus infection. CASE PRESENTATION: Case 1: A 53-year-old man with a history of non-cirrhotic chronic alcohol consumption was admitted to the intensive care unit (ICU) for septic shock and disseminated intravascular coagulopathy (DIC) of unknown origin. Blood cultures remained negative and a 16S rRNA PCR was performed leading to the identification of Capnocytophaga Canimorsus on day 4. Targeted antibiotic therapy with ceftriaxone for 14 days lead to overall recovery. Afterwards, the patient recalled a dog bite 2 days before hospitalization with a punctiform necrotic wound localized on a finger, which was not obvious at admission. Case 2: A 38-year-old man arrived to the emergency department for acute alcohol intoxication and history of a dog bite 2 days before. At admission, septic shock with purpura fulminans was diagnosed and required ICU hospitalization, invasive mechanical ventilation, vasopressor support and renal replacement therapy due to the rapid clinical deterioration. In the context of septic shock with purpura fulminans, DIC and recent dog bite, the diagnosis of Capnocytophaga canimorsus septic shock was suspected, and early confirmed by 16S rRNA PCR coupled to Sanger sequencing on day 2. Blood cultures became only positive for Capnocytophaga canimorsus 5 days after admission. Ceftriaxone alone was infused for 10 days in total, and the patient was discharged from the ICU on day 25. CONCLUSIONS: 16S rRNA gene PCR proves an important diagnostic tool when facing a sepsis of unknown origin. In these two cases of septic shock related to Capnocytophaga canimorsus, initial blood cultures remained negative at 24 h, whereas the diagnosis was achieved by 16S rRNA PCR sequencing performed from blood samples obtained at admission.

Integrons, a predictive biomarker for antibiotic resistance in acute sepsis: the IRIS study.

BACKGROUND: Considering the increase in MDR Gram-negative bacteria (GNB), the choice of empirical antibiotic therapy is challenging. In parallel, use of broad-spectrum antibiotics should be avoided to decrease antibiotic selection pressure. Accordingly, clinicians need rapid diagnostic tools to narrow antibiotic therapy. Class 1-3 integrons, identified by intI1-3 genes, are genetic elements that play a major role in antibiotic resistance in GNB. OBJECTIVES: The objective of the IRIS study was to evaluate the negative and positive predictive values (NPVs and PPVs, respectively) of intI1-3 as markers of antibiotic resistance. METHODS: The IRIS study was an observational cross-sectional multicentre study that enrolled adult subjects with suspected urinary tract or intra-abdominal infections. intI1-3 were detected directly from routinely collected biological samples (blood, urine or intra-abdominal fluid) using real-time PCR. A patient was considered 'MDR positive' if at least one GNB, expressing acquired resistance to at least two antibiotic families among ß-lactams, aminoglycosides, fluoroquinolones and/or co-trimoxazole, was isolated from at least one biological sample. RESULTS: Over a 2 year period, 513 subjects were enrolled and 409 had GNB documentation, mostly Enterobacterales. intI1 and/or intI2 were detected in 31.8% of patients and 24.4% of patients were considered 'MDR positive'. The NPV of intI1 and/or intI2 as a marker of acquired antibiotic resistances was estimated at 92.8% (89.1%-95.5%). The NPVs for first-line antibiotics were all above 92%, notably >96% for resistance to third-generation cephalosporins. CONCLUSIONS: The IRIS study strongly suggests that the absence of intI1 and intI2 in biological samples from patients with GNB-related infections is predictive of the absence of acquired resistances.

Early and specific targeted mass spectrometry-based identification of bacteria in endotracheal aspirates of patients suspected with ventilator-associated pneumonia.

Rapid and reliable pathogen identification is compulsory to confirm ventilator-associated pneumonia (VAP) in order to initiate appropriate antibiotic treatment. In the present proof of concept, the effectiveness of rapid microorganism identification with a targeted bottom-up proteomics approach was investigated in endotracheal aspirate (ETA) samples of VAP patients. To do so, a prototype selected-reaction monitoring (SRM)-based assay was developed on a triple quadrupole mass spectrometer tracking proteotypic peptide surrogates of bacterial proteomes. Through the concurrent monitoring of 97 species-specific peptides, this preliminary assay was dimensioned to characterize the occurrence of six most frequent bacterial species responsible for over more than 65% of VAP. Assay performance was subsequently evaluated by analyzing early and regular 37 ETA samples collected from 15 patients. Twenty-five samples were above the significant threshold of 105 CFU/mL and five samples showed mixed infections (both pathogens ≥ 105 CFU/mL). The targeted proteomics assay showed 100% specificity for Acinetobacter baumannii, Escherichia coli, Haemophilus influenzae, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pneumoniae. No false bacterial identification was reported and no interference was detected arising from the commensal flora. The overall species identification sensitivity was 19/25 (76%) and was higher at the patient level (84.6%). This successful proof of concept provides a rational to broaden the panel of bacteria for further clinical evaluation.

Financing Pull Mechanisms for Antibiotic-Related Innovation: Opportunities for Europe.

Antibiotic innovation is in serious jeopardy as companies continue to abandon the market due to a lack of profitability. Novel antibiotics must be used sparingly to hinder the spread of resistance, but small companies cannot survive on revenues that do not cover operational costs. When these companies either go bankrupt or move onto other therapeutic areas, these antibiotics may be no longer accessible to patients. Although significant research efforts have detailed incentives to stimulate antibiotic innovation, little attention has been paid to the financing of these incentives. In this article, we take a closer look at 4 potential financing models (diagnosis-related group carve-out, stewardship taxes, transferable exclusivity voucher, and a European-based "pay or play" model) and evaluate them from a European perspective. The attractiveness of these models and the willingness for countries to test them are currently being vetted through the European Joint Action on AMR and Healthcare-Associated Infections (EU-JAMRAI).

Proteae: a reservoir of class 2 integrons?

OBJECTIVES: Our aim was to confirm with a large panel of clinical isolates that class 2 integrons are highly prevalent in Proteae and to analyse their genetic characteristics. METHODS: Proteae (Proteus spp., Morganella spp. and Providencia spp.) isolates were collected from clinical samples during 2013 at Limoges University Hospital, France. The presence of class 1, 2 and 3 integrons was investigated by quantitative PCR. The presence of a stop codon in the intI2 gene was determined by Sanger sequencing. The gene cassette arrays of class 2 integrons were determined by PCR-RFLP and Sanger sequencing or next-generation sequencing when needed. RESULTS: Of the 327 Proteae collected, 103 (31.5%) harboured a class 2 integron and 45 (13.8%) a class 1 integron. No class 3 integrons were detected. One functional IntI2 integrase was detected in a Morganella morganii isolate. Six different gene cassette arrays were detected. Four had already been described in the literature: dfrA1-sat2-aadA1 (72 isolates), dfrA1-catB2-sat2-aadA1 (17), sat2-aadA1 (6) and lnu(F), dfrA1, aadA1 (1). We identified two new gene cassette arrays: (i) a new variant of the dfrA1 gene cassette (one isolate; the one with the functional IntI2); and (ii) the array dfrA1-gcu115-sat2 harbouring the new gcu115 gene cassette with two ORFs encoding proteins of unknown functions (five isolates). CONCLUSIONS: We showed a high frequency of class 2 integrons, as well as a diversity of gene cassette arrays, among Proteae. This work highlights that the Proteae tribe plays an important role as a reservoir of class 2 integrons.

Emergence and Within-Host Genetic Evolution of Methicillin-Resistant Staphylococcus aureus Resistant to Linezolid in a Cystic Fibrosis Patient.

Methicillin-resistant Staphylococcus aureus (MRSA) infection has increased in recent years among cystic fibrosis (CF) patients. Linezolid (LZD) is one of the antistaphylococcal antibiotics widely used in this context. Although LZD resistance is rare, it has been described as often associated with long-term treatments. Thirteen MRSA strains isolated over 5 years from one CF patient were studied for LZD resistance emergence and subjected to whole-genome sequencing (WGS). Resistance emerged after three 15-day LZD therapeutic regimens over 4 months. It was associated with the mutation of G to T at position 2576 (G2576T) in all 5 rrl copies, along with a very high MIC (>256 mg/liter) and a strong increase in the generation time. Resistant strains isolated during the ensuing LZD therapeutic regimens and until 13 months after LZD stopped harbored only 3 or 4 mutated rrl copies, associated with lower MICs (8 to 32 mg/liter) and low to moderate generation time increases. Despite these differences, whole-genome sequencing allowed us to determine that all isolates, including the susceptible one isolated before LZD treatment, belonged to the same lineage. In conclusion, LZD resistance can emerge rapidly in CF patients and persist without linezolid selective pressure in colonizing MRSA strains belonging to the same lineage.

Expression of the aac(6')-Ib-cr Gene in Class 1 Integrons.

aac(6')-Ib-cr is a plasmid-mediated quinolone resistance gene embedded within a gene cassette, most often within an integron. It confers resistance to quinolones and aminoglycosides. We investigated the role of a 101-bp fragment frequently present upstream of the aac(6')-Ib-cr gene cassette and found that it contributes to the expression of aac(6')-Ib-cr and provides an alternative start codon, confirming the length of the AAC(6')-Ib-cr protein to 199 amino acids.

Neisseria meningitidis Type IV Pili Composed of Sequence Invariable Pilins Are Masked by Multisite Glycosylation.

The ability of pathogens to cause disease depends on their aptitude to escape the immune system. Type IV pili are extracellular filamentous virulence factors composed of pilin monomers and frequently expressed by bacterial pathogens. As such they are major targets for the host immune system. In the human pathogen Neisseria meningitidis, strains expressing class I pilins contain a genetic recombination system that promotes variation of the pilin sequence and is thought to aid immune escape. However, numerous hypervirulent clinical isolates express class II pilins that lack this property. This raises the question of how they evade immunity targeting type IV pili. As glycosylation is a possible source of antigenic variation it was investigated using top-down mass spectrometry to provide the highest molecular precision on the modified proteins. Unlike class I pilins that carry a single glycan, we found that class II pilins display up to 5 glycosylation sites per monomer on the pilus surface. Swapping of pilin class and genetic background shows that the pilin primary structure determines multisite glycosylation while the genetic background determines the nature of the glycans. Absence of glycosylation in class II pilins affects pilus biogenesis or enhances pilus-dependent aggregation in a strain specific fashion highlighting the extensive functional impact of multisite glycosylation. Finally, molecular modeling shows that glycans cover the surface of class II pilins and strongly decrease antibody access to the polypeptide chain. This strongly supports a model where strains expressing class II pilins evade the immune system by changing their sugar structure rather than pilin primary structure. Overall these results show that sequence invariable class II pilins are cloaked in glycans with extensive functional and immunological consequences.

Outbreak of Panton-Valentine Leukocidin-Associated Methicillin-Susceptible Staphylococcus aureus Infection in a Rugby Team, France, 2010-2011.

Staphylococcus aureus strains that produce Panton-Valentine leukocidin are known to cause community infections. We describe an outbreak of skin abscesses caused by Panton-Valentine leukocidin-producing methicillin-susceptible S. aureus (clonal complex 121) in a professional rugby team in France during July 2010-February 2011. Eight team members were carriers; 7 had skin abscesses.