Use of a Commercially Available Microarray to Characterize Antibiotic-Resistant Clinical Isolates of Klebsiella pneumoniae.

A commercially available microarray (IDENTIBAC AMR-ve) for the detection of antibiotic resistance determinants was investigated for its potential to genotype 30 clinical isolates and two control strains of Klebsiella pneumoniae. Resistance profiles and the production of extended-spectrum ß-lactamases were determined by disc diffusion and the results were compared with the microarray profiles in order to assess its scope and limitations. Genes associated with resistance to a wide range of antibiotics, including current first line therapy options, were detected. In addition, the array also detected class 1 integrases. The array is easy to use and interpret, and is useful in providing a general description of the numbers and types of resistance determinants in K. pneumoniae. It also provides an indication of the potential for resistance gene acquisition. However, in most instances detected resistance to specific antibiotics could not unequivocally be assigned to hybridization with a specific array probe. We conclude that the microarray is a valuable and rapid means of investigating the presence of resistance gene classes of therapeutic importance. It can also provide a starting point for selecting analyses of greater resolving power, such as phylogenetic subtyping by PCR sequencing.

Proteobacteria, extremophiles and unassigned species dominate in a tape-like showerhead biofilm

Abstract The development of showerhead biofilms exposes the user to repeated contact with potentially pathogenic microbes, yet we know relatively little about the content of these aggregates. The aim of the present study was to examine the microbial content of tape-like films found protruding from a domestic showerhead. Culturing showed that the films were dominated by aerobic α- and β-proteobacteria. Three isolates made up almost the entire plate count. These were a Brevundimonas species, a metalophilic Cupriavidus species and a thermophile, Geobacillus species. Furthermore, it was shown that the Cupriavidus isolate alone had a high capacity for biofilm formation and thus might be the initiator of biofilm production. A clone library revealed the same general composition. However, half of the 70 clones analyzed could not be assigned to a particular bacterial phylum and of these 29 differed from one another by only 1–2 base pairs, indicating a single species. Thus both the culture dependent and culture independent characterizations suggest a simple yet novel composition. The work is important as the biofilm is fundamentally different in form (tape-like) and content from that of all previously reported ones, where variously Mycobacterium, Methylobacterium and Xanthomonas species have dominated, and extremophiles were not reported.

Proteobacteria, extremophiles and unassigned species dominate in a tape-like showerhead biofilm.

The development of showerhead biofilms exposes the user to repeated contact with potentially pathogenic microbes, yet we know relatively little about the content of these aggregates. The aim of the present study was to examine the microbial content of tape-like films found protruding from a domestic showerhead. Culturing showed that the films were dominated by aerobic α- and ß-proteobacteria. Three isolates made up almost the entire plate count. These were a Brevundimonas species, a metalophilic Cupriavidus species and a thermophile, Geobacillus species. Furthermore, it was shown that the Cupriavidus isolate alone had a high capacity for biofilm formation and thus might be the initiator of biofilm production. A clone library revealed the same general composition. However, half of the 70 clones analyzed could not be assigned to a particular bacterial phylum and of these 29 differed from one another by only 1-2 base pairs, indicating a single species. Thus both the culture dependent and culture independent characterizations suggest a simple yet novel composition. The work is important as the biofilm is fundamentally different in form (tape-like) and content from that of all previously reported ones, where variously Mycobacterium, Methylobacterium and Xanthomonas species have dominated, and extremophiles were not reported.

Treatment stage associated changes in cellular and molecular microbial markers during the production of drinking water at the Vansjø water works.

The production of a drinking water that meets current aesthetic, microbiological and chemical standards, generally requires a combination of mechanical purification and disinfection in a multi-component treatment chain. Treatment choices and optimisation of water processing is best informed by using markers (including microbiological parameters) which indicate how each stage contributes to the production of the potable water. The present study combines culture-based and a number of culture-independent analyses to indicate what is happening at each stage of a state-of-the-art water treatment chain at Vansjø near the city of Moss in Norway. We show that particularly clarification with flotation and post-chlorination have profound and positive effects on water quality with respect to the removal and inactivation of microbes. Post-chlorination achieved better disinfection of the water than UV-treatment and was of paramount importance, as the penultimate step filtration through granular activated shed microbes to the water. Cloning and sequencing showed that some clones present in the raw water were detected at all stages in the treatment process, perhaps providing examples of microbes breaching physically all barriers in the treatment process. Results from the study should be useful in the improvement and maintenance of the treatment process at the Vansjø plant and others.

Toxin production and antibiotic resistances in Escherichia coli isolated from bathing areas along the coastline of the Oslo fjord.

The presence of enterovirulent and/or antibiotic resistant strains of Escherichia coli in recreational bathing waters would represent a clear health issue. In total, 144 E. coli isolated from 26 beaches along the inner Oslo fjord were examined for virulence determinants and resistance to clinically important antibiotics. No isolates possessed the genetic determinants associated with enterotoxigenic strains and none showed the prototypic sorbitol negative, O157:H7 phenotype. A small number (∼1 %) produced alpha-hemolysin. Occurrences and patterns of antibiotic resistances were similar to those of E. coli isolated previously from environmental samples. In total, 6 % of the strains showed one or more clinically relevant resistances and 1.4 % were multi-drug resistant. Microarray analyses suggested that the resistance determinants were generally associated with mobile genetic elements. Resistant strains were not clonally related, and were, furthermore not concentrated at one or a few beach sites. This suggests that these strains are entering the waters at a low rate but in a widespread manner. The study demonstrates that resistant E. coli are present in coastal bathing waters where they can come into contact with bathers, and that the resistance determinants are potentially transferable. Some of the resistances registered in the study are to important antibiotics used in human medicine such as fluoroquinolones. The spread of antibiotic resistant genes, from the clinical setting to the environment, has clear implications with respect to the current management of bacterial infections and the long term value of antimicrobial therapy. The present study is the first of its kind in Norway.

[Changes in antibiotic consumption among day-care children in Oslo]. / Endringer i antibiotikaforbruk hos barnehagebarn i Oslo.

BACKGROUND: Day-care children in Oslo had a high proportion of infections (97 %) and a high consumption of antibiotics (65 %) in 2000. The study from 2000 was repeated in 2006 to see if prescriptions for antibiotics had changed. MATERIAL AND METHODS: Parents in 22 randomly chosen day-care centres in Oslo answered a questionnaire about their children (concerning infections, contact with physicians and antibiotic treatment). RESULTS: 605 parents (53 %) participated. The proportion of children treated for infections was reduced from 65 % (95 % confidence interval 61 - 69 %) in 2006 to 50 (46 - 54) % in 2000 and infections treated were reduced from 29 (26 - 32) % to 20 (17 - 23) %. Ear infections were treated in 62 % of the children in 2006 (75 % in 2000) and throat infections in 53 % (85 % in 2000) of the cases. Medical consultations resulted in prescription in 50 % of the cases in 2006 and 80 % in 2000. INTERPRETATION: Day-care children in Oslo used significantly less antibiotics and had significantly fewer medical consultations in 2006 than in 2000.

[Parents' attitudes to the prescription of antibiotics to children]. / Foreldres syn på bruk av antibiotika hos barn.

BACKGROUND: Most children in day care get infections and are prescribed antibiotics. We studied parents' attitude towards such prescription. MATERIAL AND METHODS: Parents (563 out of 1126 surveyed) in 22 day care centres returned a questionnaire on factors in their own situation and in their day care centre with impact on the use of antibiotics. RESULTS: Parents above 30 years of age, well educated and knowledgeable about antibiotics were the most sceptical of such treatment. A negative attitude on the part of employers and colleagues towards absence from work led to more use of antibiotics (p < 0.01). Children in single-parent homes were given more antibiotics than those in two-parent homes (p < 0.05). Help from relatives led to less use of antibiotics (p < 0.01). Sick children went to day care in 16% of cases; 57% of those taking antibiotics still went to day care. INTERPRETATION: Parents' situation may influence the use of antibiotics in children. Too many children are taking antibiotics and still go to day care. Support in the workplace, from relatives and from friends may give parents a better chance of staying at home with a sick child, thus preventing the spread of infections and cut down on the use of antibiotics.

[Parents' attitude to physician's role in the prescription of antibiotics to their children]. / Foreldres syn på legens rolle ved antibiotikabruk hos barna.

BACKGROUND: Most children in day care get infections and are given antibiotics. In physicians' view, the main reason for excessive use is pressure exerted on them by anxious parents. We studied parents' view of physicians' influence on the use of antibiotics. MATERIAL AND METHOD: 563 parents (50%) in 22 day care centers returned a questionnaire about their children's infections, use of antibiotics, and their experience with the doctors treating their child. RESULTS: 70% of parents had confidence in physicians' decisions. Confidence was significantly higher in doctors that they regularly consulted than in others (p = 0.001). 33% had moved on to a new physician on account of too much use of antibiotics (p < 0.05); these parents' children had received more antibiotics than other children (p < 0.05). Parents were dissatisfied with the time set aside for the consultation and with doctors' information and follow up. They expected advice and guidance, not necessarily a prescription. 47% thought that too much antibiotics are prescribed. Satisfaction was associated with less antibiotics for their own child (p < 0.001). Some parents regarded the prescription of antibiotics as doctors' way of saving time and bringing the consultation to an end. INTERPRETATION: Parents are sceptical of the use of antibiotics in children. More time set aside for the consultation is significantly associated with less use of antibiotics. Better doctor-parent communication may reduce excessive use.

[Children in day care centers--infections and use of antibiotics]. / Barn i barnehager--infeksjoner og bruk av antibiotika.

BACKGROUND: Bacterial resistance is a major problem in many countries and is associated with liberal use of antibiotics. In this study infections and use of antibiotics were studied in day-care children in Oslo and Akershus counties in Norway. MATERIAL AND METHODS: Parents in 22 randomly chosen day-care centers were asked to complete a semi-structured questionnaire about infections and antibiotic treatment of their children over the last 12 months. Out of 1,126 parents, 563 (50%) completed the questionnaire. RESULTS: 97% of the children had suffered infections over the last 12 months (mean seven infections); colds 85%, otitis 36%, throat infections 27%, bronchitis 13%, pneumonia 12%, eye infections 41%, gastroenteritis 63%, and wound infections 9%. Out of 3,900 episodes of infections, 29% were treated with antibiotics; in all, 65% of the children received antibiotics. 80% of parents had consulted physicians with their children: 80% of the consultations resulted in prescriptions of antibiotics. Boys had more infections than girls and used antibiotics more often. Younger children had more infections than older ones, but did not use antibiotics more often. Among children with ear infections 75% got antibiotics, throat infections 85%, bronchitis 82%, and eye infections 58%. INTERPRETATION: Children in day-care centers in the Oslo area have a high occurrence of infections, a high rate of medical consultations, and a very high use of antibiotics.