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Fusarium oxysporum is typically a soilborne fungus but can also be found in aquatic environments. In hospitals, water distribution systems may be reservoirs for the fungi responsible for nosocomial infections. F. oxysporum was previously detected in the water distribution systems of five French hospitals. Sixty-eight isolates from water representative of all hospital units that were previously sampled and characterized by translation elongation factor 1α sequence typing were subjected to microsatellite analysis and full-length ribosomal intergenic spacer (IGS) sequence typing. All but three isolates shared common microsatellite loci and a common two-locus sequence type (ST). This ST has an international geographical distribution in both the water networks of hospitals and among clinical isolates. The ST dominant in water was not detected among 300 isolates of F. oxysporum that originated from surrounding soils. Further characterization of 15 isolates by vegetative compatibility testing allowed us to conclude that a clonal lineage of F. oxysporum circulates in the tap water of the different hospitals. IMPORTANCE We demonstrated that a clonal lineage of Fusarium oxysporum inhabits the water distribution systems of several French hospitals. This clonal lineage, which appears to be particularly adapted to water networks, represents a potential risk for human infection and raises questions about its worldwide distribution.

International audience; Objective of the study. - Study of the spatio-temporal fungal colonization in a new medical mycology laboratory. Methods. - A 17-month survey of airborne fungal contamination was conducted in a new medical mycology laboratory at a tertiary care university hospital. This survey was implemented at three different periods: before the new premises were occupied (period A), during the move into the new laboratory (period B) and after resumption of the mycological activities in these new premises (period C). Results. - During period A, the airborne fungal load ranged from 2.3 to 6 cfu/m(3). The most frequently recovered airborne fungi were Penicillium spp. (75 to 100%). During period B, a dramatic increase in Penicillium chrysogenum conidia was observed in the air of the new laboratory (40 to 160 cfu/m(3)). During period C, the fungal load ranged from 4.5 to 8.4 cfu/m(3). Penicillium was the most common genus identified in rooms of the laboratory where no filamentous fungi were handled, while Aspergillus was clearly the predominant genus (78%) in the room dedicated to the culture of filamentous fungi. Conclusions. - We suggest that the specific fungal ecology in air of the room dedicated to the culture of filamentous fungi is due to the handling of a large number of medical strains of A. fumigatus.; Objectif de l’étude : Étude spatio-temporelle de la colonisation fongique dans un nouveau laboratoire de mycologie médicale. Méthodes : Durant 17 mois, l’aérocontamination fongique a été évaluée dans trois pièces d’un nouveau laboratoire de mycologie médicale d’un centre hospitalo-universitaire. Cette surveillance a été programmée à trois périodes différentes : avant l’occupation des nouveaux locaux (période A), durant l’emménagement dans le nouveau laboratoire (période B) et après la reprise des activités de mycologie médicale dans ces nouveaux locaux (période C). Résultats : Durant la période A, la charge fongique dans l’air était comprise entre 2,3 et 6 ufc/m3. Le micromycète le plus fréquemment isolé a été Penicillium spp. (75 à 100 %). Durant la période B, une très forte augmentation de la charge en conidies de Penicillium chrysogenum a été observée dans l’air du nouveau laboratoire (40 à 160 ufc/m3). Durant la période C, la charge fongique a été comprise entre 4,5 et 8,4 ufc/m3. Penicillium a été le genre le plus fréquemment identifié dans les deux pièces du laboratoire où aucun champignon filamenteux n’est manipulé, alors qu’Aspergillus a clairement été le genre prédominant (78 %) dans la pièce consacrée à la culture des champignons filamenteux. Conclusions : Nous suggérons que la manipulation d’un grand nombre de souches médicales d’Aspergillus est à l’origine de l’écologie spécifique qui existe dans la pièce du laboratoire destinée à la manipulation des champignons filamenteux.

The use of fosfomycin has been limited in therapeutics in recent years. Because it has shown good antibacterial activity in vitro and clinical efficacy in some domains, it has been proposed as an alternative to current antimicrobial agents, which are subject to increasing resistance. This paper reviews the main properties of fosfomycin and the latest publications concerning multidrug-resistant Enterobacteriaceae infections. In uncomplicated urinary tract infections, a single oral dose was found to be safe and effective. In complicated urinary tract infections, the same results were observed with several doses. In both cases, by using fosfomycin to treat infections, the use of carbapenems could be reduced, leading to lower costs and better microbial ecology. In severe infections, combinations with intravenous fosfomycin need to be explored further because its future activity may depend on choosing a good partner drug. Because of the fast evolution of microbial resistance, more studies are urgently needed.

Background: The Dijon University Hospital in Dijon, France is involved in a large construction program with heavy truck traffic and a very dusty environment. This study aimed to assess the impact of outdoor hospital construction work on Aspergillus air contamination in the immediate environment of patients at high risk for aspergillosis in the presence of protective measures. Methods: Prospective air and surface sampling (n 5 1301) was performed in 3 hospital units over a 30-month period. Generalized estimating equations were used to test the relationship between Aspergillus air contamination and the different variables (construction period, air treatment system, and surface contamination). Results: Positivity rates of Aspergillus spp varied from 21.1% before construction work to 16.9% during work for air samples (P 5 .07), and the associated mean fungal load varied from 1.21 colony-forming units (CFU)/m 3 to 0.64 CFU/m 3 (P 5 .04). In multivariate analysis, only the use of an air treatment system was associated with decreased airborne Aspergillus contamination (P , .0001). No significant difference was observed between the presence or absence of construction work and the proportion of airborne Aspergillus contamination (P 5 .91) or the Aspergillus fungal load (P 5 .10). Conclusions: No influence of hospital construction work on airborne Aspergillus contamination was demonstrated when protective measures were taken, including reinforcement of the importance of environmental cleaning.

International audience; An 18-month survey of indoor fungal contamination was conducted in one haematology unit during a period of construction work. Air was sampled with a portable Air System Impactor and surfaces with contact Sabouraud plates. During this survey the mean concentration of viable fungi in air was 4.2 cfu/m(3) and that for surfaces was 1.7 cfu/plate. At the beginning of construction work, there were increases in airborne fungal spores (from 3.0 to 9.8 cfu/m(3)) in the unit, but concentrations did not exceed 10 cfu/m(3) during the 18-month period. The most frequently recovered airborne fungi were Penicillium spp. (27-38%), Aspergillus spp. (25%) and Bjerkandera adusta, a basidiomycete identified with molecular tools (7-12%). Blastomycetes accounted for more than 50% of the fungal flora on surfaces. Investigating the impact of a new air-treatment system (mobile Plasmair units), there were significant reductions in fungal contamination for the Plasmer -treated rooms, and in these rooms we observed the same level of fungal load whether construction work was in progress or not.

Although the currently used live attenuated measles vaccines are safe and effective, they are dependent on cold chain maintenance and are often ineffective in young infants due to interference by maternal antibody. Therefore, besides vector-based vaccines, different new generation non-replicating candidate measles vaccines are being considered, including nucleic acid vaccines. We have vaccinated cynomolgus macaques transdermally with DNA plasmids encoding measles virus (MV) proteins. Following two vaccinations, low serum antibody responses were detected. Wild-type measles virus challenge 1 year after vaccination showed reduced viraemia in some animals. However, accelerated humoral- and cellular-immune responses were observed in all vaccinated macaques, demonstrating successful priming by the DNA vaccines.

SPE IPM MERS EA; International audience; Members of the Fusarium group were recently detected in water distribution systems of several hospitals in the world. An epidemiological investigation was conducted over 2 years in hospital buildings in Dijon and Nancy (France) and in non-hospital buildings in Dijon. The fungi were detected only within the water distribution systems of the hospital buildings and also, but at very low concentrations, in the urban water network of Nancy. All fungi were identified as Fusarium oxysporum species complex (FOSC) and Fusarium dimerum species complex (FDSC) by sequencing part of the translation elongation factor 1- alpha (TEF-1a) gene. Very low diversity was found in each complex, suggesting the existence of a clonal population for each. Density and heterogeneous distributions according to buildings and variability over time were explained by episodic detachments of parts of the colony from biofilms in the pipes. Isolates of these waterborne populations as well as soilborne isolates were tested for their ability to grow in liquid medium in the presence of increasing concentrations of sodium hypochlorite, copper sulfate, anti-corrosion pipe coating, at various temperatures (4 e42 C) and on agar medium with amphotericin B and voriconazole. The waterborne isolates tolerated higher sodium hypochlorite and copper sulfate concentrations and temperatures than did soilborne isolates but did not show any specific resistance to fungicides. In addition, unlike waterborne isolates, soilborne isolates did not survive in water even supplemented with glucose, while the former developed in the soil as well as soilborne isolates. We concluded the existence of homogeneous populations of FOSC and FDSC common to all contaminated hospital sites. These populations are present at very low densities in natural waters, making them difficult to detect, but they are adapted to the specific conditions offered by the complex water systems of public hospitals in Dijon and Nancy and probably other localities in the world.

En tant que biologistes impliques dans l’accreditation de notre laboratoire, notre attention a ete attiree par l’article de Vedy [1] « Verification sur site en microbiologie : exemple du Bact’Alert 3D (Biomerieux©) Ann Biol Clin 2013 ; 71 : 353-61 ». Cet article propose a vos lecteurs une methode de verification qui, si elle satisfait aux exigences theoriques de la norme EN ISO 15189, ne satisfait pas aux notres en termes de controle de qualite.Dans cet article ou l’auteur [...]

La decouverte de micromycetes du genre Fusarium dans le reseau hydrique du CHU de Dijon nous a conduit a mettre en place un protocole hospitalier de recherche clinique (PHRC) dont l’objectif a ete de decrire en prospectif, dans le temps et dans l’espace, la contamination par Fusarium dans l’eau de 2 CHU francais (Dijon et Nancy), a des periodes d’activites de restructuration et de construction. Cette etude a ainsi permis de mettre en evidence la presence chronique de Fusarium spp. dans les circuits de distribution de l’eau de certains bâtiments hospitaliers. Nous avons en effet observe que ces micromycetes etaient « installes » dans le reseau, que leur densite de population variait au cours du temps malgre : – le traitement chlore de l’eau ; – l’existence de portions de la tuyauterie en cuivre (liberant des ions Cu susceptibles d’inhiber le developpement des champignons) ; – l’absence a priori de sources de C et N utilisables comme substrat de croissance par les champignons. L’identification des souches par biologie moleculaire (amplification du gene du facteur d’elongation TEF-1-alpha ; par les amorces EF1 et EF2) a permis de montrer la presence de 2 especes de Fusarium dans le reseau hydrique du CHU : Fusarium oxysporum (majoritaire) et F. dimerum . A notre surprise, ces 2 memes especes ont egalement ete retrouvees dans les prelevements d’eau de Nancy. En utilisant d’autres outils de biologie moleculaire, mais aussi une etude de compatibilite vegetative, il a ete possible de montrer l’existence de populations clonales de Fusarium (especes oxysporum et dimerum ), presentes a la fois dans le reseau d’eau de Dijon (Bocage et hopital general), celui du CHU de Nancy, mais egalement dans les circuits d’alimentation en eau d’hopitaux d’autres pays du monde. A ce stade, nous avons donc emis l’hypothese que certaines souches de Fusarium etaient donc plus adaptees a une vie en milieu aquatique que d’autres souches, et qu’il serait interessant de comparer le comportement phenotypique de ces souches hydriques avec des souches de Fusarium d’origine tellurique (le sol etant le reservoir naturel du champignon). Divers tests en microplaques ont donc ete mis au point pour confirmer cette hypothese. Nous avons ainsi compare la tolerance de souches hydriques ou telluriques vis-a-vis de divers agents chimiques comme le chlore ou le cuivre (element fongistatique), et nous avons par exemple pu constater une meilleure tolerance au cuivre de la part de tous les isolats d’origine hydrique. Enfin, des etudes de dynamique de population ont egalement ete envisagees pour mieux comprendre le comportement atypique de ces souches isolees de l’eau. Les resultats obtenus nous a permis de conclure que nous etions en presence de souches fongiques de Fusarium particulierement adaptees a une vie en milieu aquatique.

Impact de la decontamination de l’air par l’utilisation du systeme Plasmair sur la survenue d’aspergilloses pulmonaires invasives chez des patients atteints de leucemies aigues recevant des chimiotherapies intensives. Experience du service d’hematologie clinique, CHU Dijon D. Caillot *, F. Dalle , M. Sautour , I. Lafon , E. Ferrant , J.-N. Bastie , B. Cuisenier , K. Astruc , S. Aho c a Service d’hematologie clinique, CHU de Dijon, Dijon, France b Laboratoire de mycologie-parasitologie, CHU de Dijon, Dijon, France c Service d’hygiene hospitaliere, CHU de Dijon, Dijon, France *Auteur correspondant.

Dijon Hospital is a French tertiary care institution undergoing major renovation, and different microbiological controls revealed the presence of Fusarium spp. in the water distribution system. Because some Fusarium spp. can cause life-threatening opportunistic infections in immunocompromised patients, an 8-month survey was conducted in two hospital sites in order to evaluate the prevalence of the fungi in the water system. In 2 units of one hospital site, 100% of the samples of tap-water were positive, with high concentrations of Fusarium spp. (up to 10 5 cfu/L). In the second hospital site, 94% of samples were positive, but generally with lower concentrations. The analysis of translation elongation factor 1α (TEF) sequences of 146 isolates revealed the presence of two different Fusarium species: F. oxysporum was detected in all units explored of both hospital sites, and F. dimerum only in one unit of one hospital site. For both species, we suggest that the fungi discovered could be particularly adapted to an aquatic environment.

International audience; A one-year prospective survey of fungal air contamination was conducted in outdoor air and inside two haematological units of a French hospital. Air was sampled with a portable Air System Impactor. During this period of survey, the mean viable fungal load was 122.1 cfu/m(3) in outdoor air samples, and 4.1 and 3.9 cfu/m(3) in samples from adult and pediatric haematology units, respectively. In outdoor samples, Cladosporium was the dominant genus (55%) while in the clinical units, Penicillium sp. (23 to 25%), Aspergillus sp. (15 to 23%) and Bjerkandera adusta (11 to 13%) were the most frequently recovered airborne fungi. The outdoor fungal load was far higher in autumn (168 cfu/m(3)), spring (110 cfu/m(3)) and summer (138 cfu/m(3)) than in winter (49 cfu/m(3)). In indoor air, fungal concentrations were significantly lower in winter (2.7 to 3.1 cfu/m(3)) than in summer (4.2 to 5.0 cfu/m(3)) in both haematology units. In the outdoor environment, Penicillium sp. and Aspergillus sp. were more abundant in winter while the levels of Cladosporium were lowest during this season. In the haematological units, the presence of Aspergillus sp. was stable during the year (close to 20%), Bjerkandera sp. was particularly abundant in winter (close to 30%); levels of Penicillium sp. were highest in autumn while levels of Cladosporium sp. were highest in spring and summer.

International audience; BACKGROUND: Invasive filamentous fungi infections resulting from inhalation of mold conidia pose a major threat in immunocompromised patients. The diagnosis is based on direct smears, cultural symptoms, and culturing fungi. Airborne conidia present in the laboratory environment may cause contamination of cultures, resulting in false-positive diagnosis. Baseline values of fungal contamination in a clinical mycology laboratory have not been determined to date. METHODS: A 1-year prospective survey of air and surface contamination was conducted in a clinical mycology laboratory during a period when large construction projects were being conducted in the hospital. Air was sampled with a portable air system impactor, and surfaces were sampled with contact Sabouraud agar plates. The collected data allowed the elaboration of Shewhart graphic charts. RESULTS: Mean fungal loads ranged from 2.27 to 4.36 colony forming units (cfu)/m(3) in air and from 0.61 to 1.69 cfu/plate on surfaces. CONCLUSIONS: Strict control procedures may limit the level of fungal contamination in a clinical mycology laboratory even in the context of large construction projects at the hospital site. Our data and the resulting Shewhart graphic charts provide baseline values to use when monitoring for inappropriate variations of the fungal contamination in a mycology laboratory as part of a quality assurance program. This is critical to the appropriate management of the fungal risk in hematology, cancer and transplantation patients.

International audience

We have studied the immune responses to the two glycoproteins of the Morbillivirus canine distemper virus (CDV) after DNA vaccination of BALB/c mice. The plasmids coding for both CDV hemagglutinin (H) and fusion protein (F) induce high levels of antibodies which persist for more than 6 months. Intramuscular inoculation of the CDV DNA induces a predominantly immunoglobulin G2a (IgG2a) response (Th1 response), whereas gene gun immunization with CDV H evokes exclusively an IgG1 response (Th2 response). In contrast, the CDV F gene elicited a mixed, IgG1 and IgG2a response. Mice vaccinated (by gene gun) with either the CDV H or F DNA showed a class I-restricted cytotoxic lymphocyte response. Immunized mice challenged intracerebrally with a lethal dose of a neurovirulent strain of CDV were protected. However, approximately 30% of the mice vaccinated with the CDV F DNA became obese in the first 2 months following the challenge. This was not correlated with the serum antibody levels.