Molecular epidemiology and genetic linkage of macrolide and aminoglycoside resistance in Staphylococcus intermedius of canine origin

A collection of 77 Staphylococcus intermedius isolates from dogs and cats in Switzerland was examined for resistance to erythromycin. Resistance profiles for 14 additional antibiotics were compared between erythromycin-resistant and susceptible isolates. A resistance prevalence of 27% for erythromycin was observed in the population under study. Complete correlation between resistance to erythromycin, and to spiramycin, streptomycin, and neomycin was observed. The erythromycin-resistant isolates all had a reduced susceptibility to clindamycin when compared to the erythromycin-susceptible isolates. Both constitutive and inducible resistance phenotypes were observed for clindamycin. Ribotyping showed that macrolide-aminoglycoside resistance was randomly distributed among unrelated strains. This suggests that this particular resistance profile is not related to a single bacterial clone but to the horizontal transfer of resistance gene clusters in S. intermedius populations. The erythromycin-resistant isolates were all carrying erm(B), but not erm(A), erm(C), or msr(A). The erm(B) gene was physically linked to Tn5405-like elements known as resistance determinants for streptomycin, streptothricin, neomycin and kanamycin. Analysis of the region flanking erm(B) showed the presence of two different groups of erm(B)-Tn5405-like elements in the S. intermedius population examined and of elements found in Gram-positive species other than staphylococci. This strongly suggests that erm(B) or the whole erm(B)-Tn5405-like elements in S. intermedius originate from other bacterial species, possibly from enterococci.

Évaluation in vitro de la stérilisation au peroxyde d'hydrogène sur les propriétés biologiques de prothèses utilisées lors de stabilisation du genou chez le chien

Objectif—Comparer les effets de la stérilisation au plasma de gaz de peroxyde d’hydrogène (HPGP) à l’oxyde d’éthylène (EO) et à la vapeur (ST) sur les propriétés physico-chimiques et d’adhésion bactérienne de fils de nylon et de polyéthylène. Design expérimental—Etude in vitro. Matériel—Des brins non stérilisés, stérilisés au HPGP, à l’EO et ST; de fil nylon leader (FNL), de fil de nylon pêche (FNP) et de fil de polyéthylène (PE) ont été utilisés. Méthodes—Une analyse de surface au spectroscope photo-électronique à rayons X (XPS), une mesure de l’angle de contact, une analyse par microscopie à force atomique (AFM) et l’adhésion bactérienne de Staphylococcus intermedius et d’Escherichia Coli ont été testés sur les brins. Résultats—Une oxydation de la surface de tous les échantillons stérilisés a été observée quelque soit la méthode de stérilisation. La stérilisation a augmenté significativement l’angle de contact pour tous les types de fil quelque soit la méthode. La rugosité n’a pas été affectée significativement par la méthode de stérilisation pour le FNL et FNP. L’adhésion bactérienne a été affectée significativement par la méthode de stérilisation. Le PE a un angle de contact, une rugosité et une adhésion bactérienne significativement plus élevée que le FNL et FNP, peu importe la méthode de stérilisation. Conclusion—La stérilisation au HPGP constitue une alternative intéressante à la vapeur et l’EO. Le PE n’est peut être pas un matériel idéal par sa capacité d’adhésion bactérienne. De futures études sont nécessaires pour déterminer la signification clinique de ces trouvailles.

Prevalence and antimicrobial resistance patterns of methicillin-resistant staphylococci (MRS) isolated in a Veterinary Teaching Hospital in Brazil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Qualitative analysis of preputial and vaginal bacterial microbiota in owl monkeys (Aotus azarai infulatus) raised in captivity

Background: The aim of this study was to identify the aerobic bacteria of the preputial and vaginal microbiota in owl monkeys that have been raised in captivity and to evaluate the antimicrobial susceptibility of these bacteria by gender and social organization. Methods: Thirty clinically healthy Aotus azarai infulatus were used. A total of 134 samples were collected, 60 from the preputial mucosa and 74 from the vaginal mucosa. An automated system of bacterial identification was used. Results and Conclusions: Staphylococcus intermedius and Proteus mirabilis were the microorganisms that were most frequently identified according to gender and social organization. The antimicrobial susceptibility of the isolated gram-positive bacteria was similar in both sexes. However, the gram-negative strains had some differences. The aerobic bacterial population of the vaginal and preputial microbiota is similar in owl monkeys, and there are no differences in the number and bacterial species according to sex and social organization. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

Isolamento e perfil de suscetibilidade a antimicrobianos de cepas de estafilococcus resistentes à meticilina em um hosapital veterinário de ensino no Brasil

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização microbiológica, molecular e contagem de células somáticas por citometria de fluxo (Somacount 300®) e por contagem microscopia (Prescott e Breed, 1910) do leite caprino mastítico

Pós-graduação em Medicina Veterinária - FMVZ

Prevalência e etiologia da mastite bovina na bacia leiteira de Rondon do Pará, estado do Pará

O objetivo do presente trabalho foi pesquisar a prevalência e a etiologia da mastite bovina na bacia leiteira do município de Rondon do Pará, bem como avaliar o perfil de sensibilidade e resistência dos agentes isolados frente aos antimicrobianos. Foram avaliadas 237 vacas mestiças de aptidão leiteira, pertencentes a nove propriedades, as quais utilizavam ordenha manual uma vez ao dia e sistema de criação extensivo em pastagens de Brachiaria brizantha, com fornecimento de sal mineral e água ad libitum. Realizou-se o exame clínico da glândula mamária, o teste da caneca telada e o California Mastitis Test. Dos 935 quartos mamários avaliados, 6,6% apresentaram mastite subclínica, 1,3% mastite clínica e 92,1% foram negativos. As bactérias isoladas na mastite clínica foram Staphylococcus spp. coagulase negativo (25%), Staphylococcus aureus (16,7%), Streptococcus spp. (8,3%) e Corynebacterium spp. (8,3%). Na mastite subclínica foram Staphylococcus spp. coagulase negativo (32,3%), Staphylococcus aureus (17,7%), Staphylococcus intermedius (1,6%), Streptococcus spp. (4,8%), Corynebacterium spp. (4,8%) e Staphylococcus spp. coagulase negativo/S. aureus (1,6%). Não houve crescimento microbiano em 41,7% das amostras com mastite clínica e 37,1% com mastite subclínica. No antibiograma, 100% dos isolados de Staphylococcus spp. coagulase negativo, S. aureus, S. intermedius, e Streptococcus spp. foram sensíveis ao sulfazotrim. Por outro lado Corynebacterium spp. foi 100% resistente ao mesmo antimicrobiano. A cefalotina, cefoxitina e gentamicina, apresentaram eficácia frente às bactérias isoladas do gênero Staphylococcus spp., as quais neste trabalho representam a grande maioria dos agentes causadores de mastite. A mastite foi diagnosticada em todos os rebanhos pesquisados, contudo o número de animais acometidos foi considerado baixo; isso provavelmente deve-se à baixa produção de leite dos animais e a permanência do bezerro ao pé após a ordenha, o que favorece o esvaziamento da glândula mamária. Diante disso, faz-se necessário que medidas higiênico-sanitárias e de manejo sejam adotadas.

MICROBIOLOGICAL ANALYSIS OF TRADITIONALLY FERMENTED MILK SOLD IN KINIGI SECTOR OF MUSANZE DISTRICT IN RWANDA

A research work entitled: “Microbiological analysis of traditionally fermented milk (Ikivuguto) sold in Kinigi Sector of Musanze District,” was carried out at Higher Learning Institution of Applied Sciences (INES-Ruhengeri) Laboratory of Microbiology located near Volcanoes in the Northern Province of Rwanda. The main objective of this work was to determine the microbiological quality of traditionally fermented milk, which is consumed by Kinigi Center local people. The hypothesis was to analyze if traditionally fermented milk commercialized in Kinigi restaurants contained pathogenic bacteria such as fecal coliforms and Escherichia coli , in addition to staphylococci and yeasts. Milk samples were collected from Kinigi sector and examined in the microbiology laboratory in order to assess the microbiological quality and safety of traditionally fermented milk in rural areas. The samples were analyzed qualitatively and quantitatively for the microbes found in fermented milk sold in Kinigi Center, and the results were as follows: 7.21x107 CFU/ml for total counts; 3.89x107 CFU/ml for Lactobacillus ; 2.77x107 CFU/ml for yeasts; 1.196x105 CFU/ml for total coliforms; 9.63x104 CFU/ml for fecal coliforms and 8.92x103 CFU/ml for staphylococci. Biochemical tests were carried out and the results showed that identified pathogens were E. coli, Providencia alcalifaciens , and the staphylococci group. It was found that fermented milk contained genera and species of Staphylococcus haemolyticus , Staphylococcus aureus , Staphylococcus intermedius , Staphylococcus xylosus and Staphylococcus saprophyticus . Findings showed that the commercial milk samples were cross-contaminated by different pathogens from environment. These contaminations could have been due to improper handling, presence of flies, soil erosion, dust from atmosphere, as well as contaminated milk vessels or pots, stirrers and unpasteurized water. It was concluded that local farmers and milk retailers did not adhere to required hygienic conditions for milk safety. In this regard, the sold traditional fermented milk does not meet health and safety standards because people did not respect good manufacturing practices. The hypothesis and main objective were confirmed, because traditionally fermented milk of Kinigi was cross-contaminated before consumption. Thus, it would be better to train farmers in the areas of product hygiene, sanitation and safety during milking, processing and marketing.

Indicadores de qualidade, pesquisa de marcadores de virulência e multirresistência aos antimicrobianos em estirpes de Staphylococcus spp. em leite de origem bovina produzido no sistema orgânico

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Detecção de genes de entrotoxinas de Staphylococcus aureus e estafilococos coagulase negativos isolados de leite bovino e de tanques de refrigeração comunitários procedentes de pequenas propriedades da região de Bauru-SP

Pós-graduação em Medicina Veterinária - FMVZ

An investigation of contact transmission of methicillin-resistant staphylococcus aureus

Hand hygiene is critical in the healthcare setting and it is believed that methicillin-resistant Staphylococcus aureus (MRSA), for example, is transmitted from patient to patient largely via the hands of health professionals. A study has been carried out at a large teaching hospital to estimate how often the gloves of a healthcare worker are contaminated with MRSA after contact with a colonized patient. The effectiveness of handwashing procedures to decontaminate the health professionals' hands was also investigated, together with how well different healthcare professional groups complied with handwashing procedures. The study showed that about 17% (9–25%) of contacts between a healthcare worker and a MRSA-colonized patient results in transmission of MRSA from a patient to the gloves of a healthcare worker. Different health professional groups have different rates of compliance with infection control procedures. Non-contact staff (cleaners, food services) had the shortest handwashing times. In this study, glove use compliance rates were 75% or above in all healthcare worker groups except doctors whose compliance was only 27%.

Smoothing a Discrete Hazard Function for the Number of Patients Colonized with Methicillin-Resistance Staphylococcus Aureus in an Intensive Care Unit

A new method for estimating the time to colonization of Methicillin-resistant Staphylococcus Aureus (MRSA) patients is developed in this paper. The time to colonization of MRSA is modelled using a Bayesian smoothing approach for the hazard function. There are two prior models discussed in this paper: the first difference prior and the second difference prior. The second difference prior model gives smoother estimates of the hazard functions and, when applied to data from an intensive care unit (ICU), clearly shows increasing hazard up to day 13, then a decreasing hazard. The results clearly demonstrate that the hazard is not constant and provide a useful quantification of the effect of length of stay on the risk of MRSA colonization which provides useful insight.

Using a longitudinal model to estimate the effect of methicillin-resistant staphylococcus aureus infection on length of stay in an intensive care unit

Healthcare-associated methicillin-resistant Staphylococcus aureus(MRSA) infection may cause increased hospital stay or, sometimes, death. Quantifying this effect is complicated because it is a time-dependent exposure: infection may prolong hospital stay, while longer stays increase the risk of infection. We overcome these problems by using a multinomial longitudinal model for estimating the daily probability of death and discharge. We then extend the basic model to estimate how the effect of MRSA infection varies over time, and to quantify the number of excess ICU days due to infection. We find that infection decreases the relative risk of discharge (relative risk ratio = 0.68, 95% credible interval: 0.54, 0.82), but is only indirectly associated with increased mortality. An infection on the first day of admission resulted in a mean extra stay of 0.3 days (95% CI: 0.1, 0.5) for a patient with an APACHE II score of 10, and 1.2 days (95% CI: 0.5, 2.0) for a patient with an APACHE II score of 30. The decrease in the relative risk of discharge remained fairly constant with day of MRSA infection, but was slightly stronger closer to the start of infection. These results confirm the importance of MRSA infection in increasing ICU stay, but suggest that previous work may have systematically overestimated the effect size.