Comparison of two live-animal ultrasound systems for genetic evaluation of carcass traits in Angus cattle.

The improvement of carcass traits is an important breeding objective in beef cattle breeding programs. The most common way of selecting for improvement in carcass traits is via indirect selection using ultrasound scanning of selection candidates which are submitted to genetic evaluation programs. Two systems used to analyze ultrasound images to predict carcass traits are the Pie Medical Esaote Aquila (PIE) and Central Ultrasound Processing (CUP). This study compared the ability of the two systems to predict carcass traits for genetic evaluation in Australian Angus cattle. Genetic and phenotypic parameters were estimated using data from 1,648 Angus steers which were ultrasound scanned twice with both systems, first at feedlot entry and then following 100 d in the feedlot. The traits interpreted from ultrasound scanning included eye muscle area (EMA), rib fat (RIB) rump fat (RUMP), and intramuscular fat (IMF). Abattoir carcass data were collected on all steers following the full feedlot feeding period of 285 d. For all ultrasound scan traits, CUP resulted in higher phenotypic and genetic variances compared to the PIE. For IMF, CUP had higher heritability at feedlot intake (0.51 for CUP compared to 0.37 for PIE) and after 100 d feeding (0.54 for CUP compared to 0.45 PIE). CUP predicted IMF also tended to have stronger correlations with the breeding objective traits of carcass IMF and marbling traits, both genetically (ranging from 0.59 to 0.75 for CUP compared to 0.45-0.63 for PIE) and phenotypically (ranging from 0.27 to 0.43 for CUP compared to 0.19-0.28 for PIE). Ultrasound scan EMA was the only group of traits in which the heritabilities were higher for PIE (0.52 for PIE compared to 0.40 for CUP at feedlot intake and 0.46 for PIE compared to 0.43 for CUP at 100 d of feeding), however with similar relationships to the breeding objective carcass EMA observed. For subcutaneous fat traits of ultrasound RIB and RUMP, the heritabilites and genetic correlations to the related carcass traits were similar, with the exception being the higher heritability observed for CUP predicted RUMP at feedlot intake at 0.52 compared to 0.38 for PIE. The results from this study indicates that the CUP system, compared to PIE, provides an advantage for genetic evaluation of carcass traits in Angus cattle, particularly for the IMF and associated marbling traits.

Benthic responses to an Antarctic regime shift: food particle size and recruitment biology.

Polar ecosystems are bellwether indicators of climate change and offer insights into ecological resilience. In this study, we describe contrasting responses to an apparent regime shift of two very different benthic communities in McMurdo Sound, Antarctica. We compared species-specific patterns of benthic invertebrate abundance and size between the west (low productivity) and east (higher productivity) sides of McMurdo Sound across multiple decades (1960s-2010) to depths of 60 m. We present possible factors associated with the observed changes. A massive and unprecedented shift in sponge recruitment and growth on artificial substrata observed between the 1980s and 2010 contrasts with lack of dramatic sponge settlement and growth on natural substrata, emphasizing poorly understood sponge recruitment biology. We present observations of changes in populations of sponges, bryozoans, bivalves, and deposit-feeding invertebrates in the natural communities on both sides of the sound. Scientific data for Antarctic benthic ecosystems are scant, but we gather multiple lines of evidence to examine possible processes in regional-scale oceanography during the eight years in which the sea ice did not clear out of the southern portion of McMurdo Sound. We suggest that large icebergs blocked currents and advected plankton, allowed thicker multi-year ice, and reduced light to the benthos. This, in addition to a possible increase in iron released from rapidly melting glaciers, fundamentally shifted the quantity and quality of primary production in McMurdo Sound. A hypothesized shift from large to small food particles is consistent with increased recruitment and growth of sponges on artificial substrata, filter-feeding polychaetes, and some bryozoans, as well as reduced populations of bivalves and crinoids that favor large particles, and echinoderms Sterechinus neumayeri and Odontaster validus that predominantly feed on benthic diatoms and large phytoplankton mats that drape the seafloor after spring blooms. This response of different guilds of filter feeders to a hypothesized shift from large to small phytoplankton points to the enormous need for and potential value of holistic monitoring programs, particularly in pristine ecosystems, that could yield both fundamental ecological insights and knowledge that can be applied to critical conservation concerns as climate change continues.

Environmental contamination by bacteria in hospital washrooms according to hand-drying method: a multi-centre study.

BACKGROUND: Hand hygiene is a fundamental component of infection prevention, but few studies have examined whether hand-drying method affects the risk of dissemination of potential pathogens. AIM: To perform a multi-centre, internal-crossover study comparing bacterial contamination levels in washrooms with hand-drying by either paper towels (PT) or jet air dryer (JAD; Dyson). METHODS: A total of 120 sampling sessions occurred over 12 weeks in each of three hospitals (UK, France, Italy). Bacteria were cultured from air, multiple surfaces, and dust. Washroom footfall (patients/visitors/staff) was monitored externally. FINDINGS: Footfall was nine times higher in UK washrooms. Bacterial contamination was lower in PT versus JAD washrooms; contamination was similar in France and the UK, but markedly lower in Italian washrooms. Total bacterial recovery was significantly greater from JAD versus PT dispenser surfaces at all sites (median: 100-300 vs 0-10 cfu; all P < 0.0001). In the UK and France, significantly more bacteria were recovered from JAD washroom floors (median: 24 vs 191 cfu, P < 0.00001). UK meticillin-susceptible Staphylococcus aureus recovery was three times more frequent and six-fold higher for JAD vs PT surfaces (both P < 0.0001). UK meticillin-resistant S. aureus recovery was three times more frequent (21 vs 7 cfu) from JAD versus PT surfaces or floors. Significantly more enterococci and extended-spectrum ß-lactamase (ESBL)-producing bacteria were recovered from UK JAD versus PT washroom floors (P < 0.0001). In France, ESBL-producing bacteria were recovered from dust twice as often during JAD versus PT use. CONCLUSION: Multiple examples of significant differences in surface bacterial contamination, including by faecal and antibiotic-resistant bacteria, were observed, with higher levels in JAD versus PT washrooms. Hand-drying method affects the risk of (airborne) dissemination of bacteria in real-world settings.

The potential of alcohol release doorplates to reduce surface contamination during hand contact.

BACKGROUND: Optimal hand hygiene may be compromised by contact with contaminated environmental surfaces. AIM: To investigate the in-vitro efficacy of a novel alcohol-release doorplate to reduce surface contamination during hand contact. METHODS: Prototype, horizontally held, Surfaceskins, alcohol gel-impregnated and control (aluminium) doorplates were challenged (N = 72 per micro-organism) with Staphylococcus aureus-, Eschericia coli-, Enterococcus faecalis-, or Clostridium difficile-contaminated fingers. S. aureus and E. faecalis were used for challenges (90 per micro-organism) of vertical (modified design) doorplates, on days 0, 3, 4, 6, and 7. Surface contamination was measured pre and immediately post challenges using agar contact plates. FINDINGS: Horizontal test, but not control, doorplates demonstrated bacterial killing of S. aureus, E. faecalis and E. coli, but not of C. difficile; hence, only testing of S. aureus and E. faecalis was continued. Vertical Surfaceskins, but not control, doorplates demonstrated rapid killing of S. aureus over seven days. There were significant reductions (>90% up to day 6; P ≤ 0.01) of surface bacterial colony counts compared with controls immediately post challenge. There were also significant reductions in Surfaceskins doorplate enterococcal colony counts compared with controls on every day of testing (P ≤ 0.004). There was no evidence that bacterial recovery was greater from the tops of Surfaceskins doorplates (i.e. due to pooling of contents). CONCLUSION: Surfaceskins doorplates were efficient at reducing surface contamination by S. aureus, E. faecalis, and E. coli. Reducing microbial contamination of frequently touched door surfaces, and so bacterial transfer via hands, could feasibly reduce the risk of healthcare-associated and other infections.

Microbiological comparison of hand-drying methods: the potential for contamination of the environment, user, and bystander.

BACKGROUND: The efficiency of hand drying is important in preventing pathogen spread, but knowledge surrounding which drying methods contribute least towards contamination of the environment and users is limited. AIM: To compare the propensity of three common hand-drying methods (jet air, warm air dryers, and paper towels) to contaminate the environment, users, and bystanders. METHODS: Hands were coated in lactobacilli to simulate poorly washed, contaminated hands, and dried. The investigation comprised 120 air-sampling tests (60 tests and 60 controls), divided into close and 1m proximity from the drying process. Separate tests used hands coated in paint to visualize droplet dispersal. FINDINGS: Air bacterial counts in close proximity to hand drying were 4.5-fold higher for the jet air dryer (70.7 cfu) compared with the warm air dryer (15.7 cfu) (P=0.001), and 27-fold higher compared with use of paper towels (2.6 cfu) (P<0.001). Airborne counts were also significantly different during use of towel drying versus warm air dryer (P=0.001). A similar pattern was seen for bacterial counts at 1m away. Visualization experiments demonstrated that the jet air dryer caused the most droplet dispersal. CONCLUSION: Jet air and warm air dryers result in increased bacterial aerosolization when drying hands. These results suggest that air dryers may be unsuitable for use in healthcare settings, as they may facilitate microbial cross-contamination via airborne dissemination to the environment or bathroom visitors.

Population connectivity shifts at high frequency within an open-coast marine protected area network.

A complete understanding of population connectivity via larval dispersal is of great value to the effective design and management of marine protected areas (MPA). However empirical estimates of larval dispersal distance, self-recruitment, and within season variability of population connectivity patterns and their influence on metapopulation structure remain rare. We used high-resolution otolith microchemistry data from the temperate reef fish Hypsypops rubicundus to explore biweekly, seasonal, and annual connectivity patterns in an open-coast MPA network. The three MPAs, spanning 46 km along the southern California coastline were connected by larval dispersal, but the magnitude and direction of connections reversed between 2008 and 2009. Self-recruitment, i.e. spawning, dispersal, and settlement to the same location, was observed at two locations, one of which is a MPA. Self-recruitment to this MPA ranged from 50-84%; within the entire 60 km study region, self-recruitment accounted for 45% of all individuals settling to study reefs. On biweekly time scales we observed directional variability in alongshore current data and larval dispersal trajectories; if viewed in isolation these data suggest the system behaves as a source-sink metapopulation. However aggregate biweekly data over two years reveal a reef network in which H. rubicundus behaves more like a well-mixed metapopulation. As one of the few empirical studies of population connectivity within a temperate open coast reef network, this work can inform the MPA design process, implementation of ecosystem based management plans, and facilitate conservation decisions.

Effectiveness of deep cleaning followed by hydrogen peroxide decontamination during high Clostridium difficile infection incidence.

BACKGROUND: Clostridium difficile infection (CDI) remains an infection control challenge, especially when environmental spore contamination and suboptimal cleaning may increase transmission risk. AIM: To substantiate the long-term effectiveness throughout a stroke rehabilitation unit (SRU) of deep cleaning and hydrogen peroxide decontamination (HPD), following a high incidence of CDI. METHODS: Extensive environmental sampling (342 sites on each occasion) for C. difficile using sponge wipes was performed: before and after deep cleaning with detergent/chlorine agent; immediately following HPD; and on two further occasions, 19 days and 20 weeks following HPD. C. difficile isolates underwent polymerase chain reaction ribotyping and multi-locus variable repeat analysis (MLVA). FINDINGS: C. difficile was recovered from 10.8%, 6.1%, 0.9%, 0% and 3.5% of sites at baseline, following deep cleaning, immediately after HPD, and 19 days and 20 weeks after HPD, respectively. C. difficile ribotypes recovered after deep cleaning matched those from CDI cases in the SRU during the previous 10 months. Similarly, 10/12 of the positive sites identified at 20 weeks post-HPD harboured the same C. difficile ribotype (002) and MLVA pattern as the isolate from the first post-HPD CDI case. CDI incidence [number of cases on SRU per 10 months (January-October 2011)] declined from 20 before to seven after the intervention. CONCLUSION: HPD, after deep cleaning with a detergent/chlorine agent, was highly effective for removing environmental C. difficile contamination. Long-term follow-up demonstrated that a CDI symptomatic patient can rapidly recontaminate the immediate environment. Determining a role for HPD should include long-term cost-effectiveness evaluations.

Global conservation outcomes depend on marine protected areas with five key features.

In line with global targets agreed under the Convention on Biological Diversity, the number of marine protected areas (MPAs) is increasing rapidly, yet socio-economic benefits generated by MPAs remain difficult to predict and under debate. MPAs often fail to reach their full potential as a consequence of factors such as illegal harvesting, regulations that legally allow detrimental harvesting, or emigration of animals outside boundaries because of continuous habitat or inadequate size of reserve. Here we show that the conservation benefits of 87 MPAs investigated worldwide increase exponentially with the accumulation of five key features: no take, well enforced, old (>10 years), large (>100 km(2)), and isolated by deep water or sand. Using effective MPAs with four or five key features as an unfished standard, comparisons of underwater survey data from effective MPAs with predictions based on survey data from fished coasts indicate that total fish biomass has declined about two-thirds from historical baselines as a result of fishing. Effective MPAs also had twice as many large (>250 mm total length) fish species per transect, five times more large fish biomass, and fourteen times more shark biomass than fished areas. Most (59%) of the MPAs studied had only one or two key features and were not ecologically distinguishable from fished sites. Our results show that global conservation targets based on area alone will not optimize protection of marine biodiversity. More emphasis is needed on better MPA design, durable management and compliance to ensure that MPAs achieve their desired conservation value.

Escherichia coli bacteraemia: 2 years of prospective regional surveillance (2010-12).

OBJECTIVES: To determine the prevalence of antibiotic resistance and the epidemiology of Escherichia coli bacteraemia isolates across the Yorkshire and Humber National Health Service region over 2 years. METHODS: Ten percent of all E. coli blood culture isolates were collected per month from 14 laboratories across the Yorkshire and Humber region. Individual laboratories submitted antibiotic susceptibility data and isolates were re-tested centrally using the VITEK2(®) system (bioMérieux, France). Isolates were also characterized using PCR to test for the presence of sequences encoding extended-spectrum ß-lactamases (ESBLs) and genotyped using amplified fragment length polymorphism (AFLP). Selected isolates were further characterized using multilocus sequence typing. RESULTS: Between July 2010 and June 2012, 770 isolates were examined: 63%, 40%, 14% and 7% of isolates were non-susceptible to ampicillin, trimethoprim, ciprofloxacin and gentamicin, respectively. Eight percent of isolates (n = 63) were ESBL positive; CTX-M group 1 enzymes were the most common (68%). There was a fluctuating trend in the prevalence of resistance to amoxicillin/clavulanic acid (MIC >8 mg/L): July-September 2010, 16%; July-September 2011, 38%; and April-June 2012, 22%. AFLP identified 106 types. The majority of isolates belonged to one of two AFLP types: AFLP 1 [sequence type (ST) 131; 17%] and AFLP 2 (ST73; 18%). ST131 and ST73 were both associated with hospital- and community-onset bacteraemia, and with urinary, hepatobiliary and gastrointestinal sources of infection. ESBL-positive isolates were predominantly ST131 (60%). CONCLUSIONS: Continued surveillance of antibiotic resistance among E. coli bacteraemia isolates is necessary to enhance these early baseline data. The variable prevalence of resistance to amoxicillin/clavulanic acid raises concerns, as both E. coli bacteraemia and empirical use of this antibiotic are common.

Meticillin-resistant Staphylococcus aureus in elderly residents of care homes: colonization rates and molecular epidemiology.

BACKGROUND: Meticillin-resistant Staphylococcus aureus (MRSA) is a significant cause of mortality and morbidity in healthcare and community settings; however, there is a paucity of large-scale, longitudinal studies monitoring the occurrence of MRSA in the care home setting. AIM: To determine the molecular epidemiology of MRSA colonizing elderly residents of care homes. METHODS: Residents in 65 care homes in Leeds, UK, were screened for MRSA nasal colonization in four consecutive years (2006-2009). Isolates were characterized using antibiotic susceptibility testing, detection of the Panton-Valentine leucocidin (PVL) locus, accessory gene regulator allotyping, characterization of the staphylococcal cassette chromosome mec element, spa-typing and pulsed-field gel electrophoresis. FINDINGS: MRSA was recovered from 888 nasal swabs of 2492 residents and prevalence was similar (19-22%) throughout the study. Resistance to ≥3 antibiotic classes was common (34%), but resistance to only ß-lactam agents was rare (3%); no PVL-positive isolates were identified. Most isolates were related to healthcare-associated epidemic-MRSA type 15 (EMRSA-15, ST22-IV); such isolates decreased in prevalence during the study (86-72%; P < 0.0001, χ(2)-test). The remainder belonged to five different multi-locus sequence type clonal complexes (CC). Most notably, CC59 strains increased in prevalence (10-25%; P < 0.0001, χ(2)-test) and were associated with high-level mupirocin resistance. CONCLUSIONS: The molecular epidemiology of MRSA in care homes is complex and dynamic. There was a high, consistent prevalence of MRSA nasal colonization, dominated by healthcare-associated strains. Vigilance is recommended; however, as high-level mupirocin resistance was associated with a single clonal group (CC59) that significantly increased in prevalence during the study.

The longitudinal prevalence of MRSA in care home residents and the effectiveness of improving infection prevention knowledge and practice on colonisation using a stepped wedge study design.

Objectives To determine the prevalence and health outcomes of meticillin-resistant Staphylococcus aureus (MRSA) colonisation in elderly care home residents. To measure the effectiveness of improving infection prevention knowledge and practice on MRSA prevalence. Setting Care homes for elderly residents in Leeds, UK. Participants Residents able to give informed consent. Design A controlled intervention study, using a stepped wedge design, comprising 65 homes divided into three groups. Baseline MRSA prevalence was determined by screening the nares of residents (n=2492). An intervention based upon staff education and training on hand hygiene was delivered at three different times according to group number. Scores for three assessment methods, an audit of hand hygiene facilities, staff hand hygiene observations and an educational questionnaire, were collected before and after the intervention. After each group of homes received the intervention, all participants were screened for MRSA nasal colonisation. In total, four surveys took place between November 2006 and February 2009. Results MRSA prevalence was 20%, 19%, 22% and 21% in each survey, respectively. There was a significant improvement in scores for all three assessment methods post-intervention (p≤0.001). The intervention was associated with a small but significant increase in MRSA prevalence (p=0.023). MRSA colonisation was associated with previous and subsequent MRSA infection but was not significantly associated with subsequent hospitalisation or mortality. Conclusions The intervention did not result in a decrease in the prevalence of MRSA colonisation in care home residents. Additional measures will be required to reduce endemic MRSA colonisation in care homes.

Global gene expression profiling reveals genes expressed differentially in cattle with high and low residual feed intake.

Feed efficiency is an economically important trait in beef production. It can be measured as residual feed intake. This is the difference between actual feed intake recorded over a test period and the expected feed intake of an animal based on its size and growth rate. DNA-based marker-assisted selection would help beef breeders to accelerate genetic improvement for feed efficiency by reducing the generation interval and would obviate the high cost of measuring residual feed intake. Although numbers of quantitative trait loci and candidate genes have been identified with the advance of molecular genetics, our understanding of the physiological mechanisms and the nature of genes underlying residual feed intake is limited. The aim of the study was to use global gene expression profiling by microarray to identify genes that are differentially expressed in cattle, using lines genetically selected for low and high residual feed intake, and to uncover candidate genes for residual feed intake. A long-oligo microarray with 24 000 probes was used to profile the liver transcriptome of 44 cattle selected for high or low residual feed intake. One hundred and sixty-one unique genes were identified as being differentially expressed between animals with high and low residual feed intake. These genes were involved in seven gene networks affecting cellular growth and proliferation, cellular assembly and organization, cell signalling, drug metabolism, protein synthesis, lipid metabolism, and carbohydrate metabolism. Analysis of functional data using a transcriptional approach allows a better understanding of the underlying biological processes involved in residual feed intake and also allows the identification of candidate genes for marker-assisted selection.

Spatial patterns of fishing effort off San Diego: implications for zonal management and ecosystem function.

The essence of ecosystem-based management is managing human practices to conserve the ecosystem. Ecologists focus on understanding the ecosystem, but there are fundamental information gaps including patterns of human exploitation. In particular, the spatial distribution of fishing effort must be known at the scales needed for ecologically relevant management. Fishing is a primary impact on coastal ecosystems, yet catch distribution at scales relevant to habitats and processes are not well known for many fisheries. Here we utilized photographic time series, logbook records, and angler surveys to estimate the intensity and spatial pattern of commercial and recreational fishing. Effort was clearly aggregated for most types of fishing, the motivating factors for effort distribution varied among areas, and effort was coupled or uncoupled to habitat depending on the area and type of fishing. We estimated that approximately 60% and approximately 74% of private recreational and recreational charter vessel fishing effort, respectively, were concentrated into two small areas that also included approximately 78% of commercial sea urchin effort. Exploitation and effort were considerably greater in one kelp forest, which has important implications for patterns of kelp persistence, productivity, and ecosystem function. Areas subject to the greatest recreational fishing pressure appeared to have lower diversity. Our results indicate that fine-scale patterns of fishing effort and exploitation have profound consequences for ecosystem functioning and biodiversity. 'Ecosystem-based management of nearshore ecosystems depends on an understanding of the fine-scale patterns of exploitation.

Discriminating sources of PCB contamination in fish on the coastal shelf off San Diego, California (USA).

Management of coastal ecosystems necessitates the evaluation of pollutant loading based on adequate source discrimination. Monitoring of sediments and fish on the shelf off San Diego has shown that some areas on the shelf are contaminated with polychlorinated biphenyls (PCBs). Here, we present an analysis of PCB contamination in fish on the shelf off San Diego designed to discriminate possible sources. The analysis was complicated by the variability of species available for analysis across the shelf, variable affinities of PCBs among species, and non-detects in the data. We utilized survival regression analysis to account for these complications. We also examined spatial patterns of PCBs in bay and offshore sediments and reviewed more than 20 years of influent and effluent data for local wastewater treatment facilities. We conclude that most PCB contamination in shelf sediments and fish is due to the ongoing practice of dumping contaminated sediments dredged from San Diego Bay.

Marine reserve design: optimal size, habitats, species affinities, diversity, and ocean microclimate.

The design of marine reserves is complex and fraught with uncertainty. However, protection of critical habitat is of paramount importance for reserve design. We present a case study as an example of a reserve design based on fine-scale habitats, the affinities of exploited species to these habitats, adult mobility, and the physical forcing affecting the dynamics of the habitats. These factors and their interaction are integrated in an algorithm that determines the optimal size and location of a marine reserve for a set of 20 exploited species within five different habitats inside a large kelp forest in southern California. The result is a reserve that encompasses approximately 42% of the kelp forest. Our approach differs fundamentally from many other marine reserve siting methods in which goals of area, diversity, or biomass are targeted a priori. Rather, our method was developed to determine how large a reserve must be within a specific area to protect a self-sustaining assemblage of exploited species. The algorithm is applicable across different ecosystems, spatial scales, and for any number of species. The result is a reserve in which habitat value is optimized for a predetermined set of exploited species against the area left open to exploitation. The importance of fine-scale habitat definitions for the exploited species off La Jolla is exemplified by the spatial pattern of habitats and the stability of these habitats within the kelp forest, both of which appear to be determined by ocean microclimate.

Surveillance for mupirocin resistance following introduction of routine peri-operative prophylaxis with nasal mupirocin.

The authors have previously described the successful use of a five-day peri-operative prophylaxis regimen using nasal mupirocin and topical triclosan (PPNMTT) to prevent methicillin-resistant Staphylococcus aureus (MRSA) infection. The present article describes the results of repeated point-prevalence surveillance for four years to determine whether mupirocin resistance has emerged in surgical units using empirical, short-term, peri-operative prophylaxis with nasal mupirocin. Before starting PPNMTT and every six months thereafter for four years, point-prevalence surveillance was performed for nasal S. aureus carriage in all patients on five orthopaedic surgery wards, one vascular surgery ward and one elderly medicine control ward. S. aureus screening and clinical isolates (surgical patients) were undertaken for low- [minimum inhibitory concentration (MIC) 8-128 mg/L] and high-level (MIC > 128 mg/L) mupirocin resistance. All isolates were phage typed to determine whether there was evidence of the spread of clonal mupirocin-resistant strains. Of 593, 139 and 206 nasal screening swabs (taken after the regimen had started) from orthopaedic, vascular and control patients, 28%, 24% and 48% (orthopaedic/vascular surgery vs elderly medicine, P < 0.001) yielded S. aureus isolates, respectively, and 12%, 11% and 30% (P < 0.001) were MRSA positive, respectively. Of the S. aureus nasal screen isolates from orthopaedic/vascular surgery and control patients, 5% and 4%, respectively, were low-level mupirocin resistant (P > 0.1). Of 286 (orthopaedic/vascular surgery) and 68 (elderly medicine) clinical S. aureus isolates obtained after the regimen had started, 7% and 9% (P > 0.1), respectively, were low-level mupirocin resistant. No high-level mupirocin-resistant isolates were isolated from mupirocin (orthopaedic/vascular surgery) or elderly medicine control ward patients. There was no trend towards increasing prevalence of low-level mupirocin resistance during the four-year study period. The results of phage typing did not support the clonal spread of resistant strains. Long-term follow-up confirmed the efficacy of PPNMTT in reducing the prevalence of nasal carriage of S. aureus and MRSA in orthopaedic and vascular surgery patients. Despite four years of use of PPNMTT, there was no evidence of sustained emergence or spread of mupirocin resistance.

Role of environmental cleaning in controlling an outbreak of Acinetobacter baumannii on a neurosurgical intensive care unit.

An outbreak of Acinetobacter baumannii colonization and infection occurred in 19 patients over a 14-month period during 1998-1999 on a neurosurgical intensive care unit. During efforts to control the outbreak a significant correlation was observed between the number of environmental isolates of A. baumannii obtained during each monthly screening and the number of patients with A. baumannii colonization/infection in the same calendar month (P=0.004). Use of 1000 ppm hypochlorite solution and the introduction of new cleaning protocols reduced the number of environmental isolates. Failure to maintain low levels of environmental contamination with A. baumannii resulted in increases in patient colonization. This study showed that high standards of cleaning play an integral role in controlling outbreaks of A. baumannii in the intensive care unit setting.

Biologic and molecular characteristics of Toxoplasma gondii isolates from striped skunk (Mephitis mephitis), Canada goose (Branta canadensis), black-winged lory (Eos cyanogenia), and cats (Felis catus).

Toxoplasma gondii isolates can be grouped into 3 genetic lineages. Type I isolates are considered virulent to outbred mice, whereas Type II and III isolates are not. In the present report, viable T. gondii was isolated for the first time from striped skunk (Mephitis mephitis), Canada goose (Branta canadensis), and black-winged lory (Eos cyanogenia). For the isolation of T. gondii, tissues were bioassayed in mice, and genotyping was based on the SAG2 locus. Toxoplasma gondii was isolated from 3 of 6 skunks, 1 of 4 Canada geese, and 2 of 2 feral cats (Felis catus) from Mississippi. All donor animals were asymptomatic. Viable T. gondii was also isolated from 5 of 5 lories that had died of acute toxoplasmosis in an aviary in South Carolina. Genotypes of T. gondii isolates were Type III (all skunks, lories, and the goose) and Type II (both cats). All 5 Type III isolates from birds and 2 of the 3 isolates from skunks were mouse virulent.