Aminoglycoside susceptibility of Pasteurella multocida isolates from bovine respiratory infections in China and mutations in ribosomal protein S5 associated with high-level induced spectinomycin resistance.

Twenty-three isolates of Pasteurella multocida were tested for susceptibility to six aminoglycoside agents and screened by polymerase chain reaction for the presence of aminoglycoside resistance genes. In addition, mutations in the resistance-determining region of strains showing a high level of induced resistance to spectinomycin strains were examined. Susceptibility testing showed that all of the isolates were resistant to at least two types of aminoglycosides, and that the most effective antimicrobial was spectinomycin. The resistance genes aphA1, strB and aacA4 were present in all 23 isolates. In the three induced spectinomycin-resistant strains, a 9-bp deletion in rpsE that encodes ribosomal protein S5 was detected.

Surveillance of antimicrobial resistance in clinical isolates of Pasteurella multocida and Streptococcus suis from Ontario swine.

Susceptibility results for Pasteurella multocida and Streptococcus suis isolated from swine clinical samples were obtained from January 1998 to October 2010 from the Animal Health Laboratory at the University of Guelph, Guelph, Ontario, and used to describe variation in antimicrobial resistance (AMR) to 4 drugs of importance in the Ontario swine industry: ampicillin, tetracycline, tiamulin, and trimethoprim-sulfamethoxazole. Four temporal data-analysis options were used: visualization of trends in 12-month rolling averages, logistic-regression modeling, temporal-scan statistics, and a scan with the "What's strange about recent events?" (WSARE) algorithm. The AMR trends varied among the antimicrobial drugs for a single pathogen and between pathogens for a single antimicrobial, suggesting that pathogen-specific AMR surveillance may be preferable to indicator data. The 4 methods provided complementary and, at times, redundant results. The most appropriate combination of analysis methods for surveillance using these data included temporal-scan statistics with a visualization method (rolling-average or predicted-probability plots following logistic-regression models). The WSARE algorithm provided interesting results for quality control and has the potential to detect new resistance patterns; however, missing data created problems for displaying the results in a way that would be meaningful to all surveillance stakeholders.

Les résultats de sensibilité pour des isolats de Pasteurella multocida et Streptococcus suis provenant d'échantillons cliniques de porcs furent obtenus du Animal Health Laboratory de l'Université de Guelph pour la période de janvier 1998 à octobre 2010, et utilisés pour décrire la variation dans la résistance antimicrobienne (AMR) à quatre antibiotiques d'importance dans l'industrie porcine en Ontario : l'ampicilline, la tétracycline, la tiamuline, et le trimethoprime-sulfaméthoxazole. Quatre options temporelles d'analyse des données ont été utilisées : visualisation des tendances des moyennes mobiles de 12 mois, modélisation de régression logistique, statistiques d'un scan temporel, et un scan avec l'algorithme «Qu'y a-t-il d'étrange avec des évènements récents?¼ (WSARE). Les tendances d'AMR variaient entre les antibiotiques pour un agent pathogène et entre les agents pathogènes pour un antibiotique unique, ce qui suggère que la surveillance AMR pour un agent pathogène spécifique serait préférable à des données indicatrices. Les quatre méthodes ont fourni des données complémentaires, et parfois des résultats redondants. La combinaison la plus appropriée de méthodes d'analyse pour la surveillance en utilisant ces données incluait les statistiques d'un scan temporel avec une méthode de visualisation (moyenne mobile ou graphes de probabilité prédite suite à des modèles de régression logistique). L'algorithme WSARE a fourni des résultats intéressants pour le contrôle de qualité et a le potentiel de détecter des nouveaux patrons de résistance; toutefois, des données manquantes ont causé des problèmes pour montrer les résultats d'une manière qui serait signifiante pour toutes les personnes concernées par la surveillance.(Traduit par Docteur Serge Messier).

A study on ovine pneumonic pasteurellosis: isolation and identification of Pasteurellae and their antibiogram susceptibility pattern in Haramaya District, Eastern Hararghe, Ethiopia.

BACKGROUND: Sheep constitute the second major component of livestock in Ethiopia. However, efficient utilization of this potential resource is hampered by combination of health problems, poor management and feed shortage. Haramaya district is one of the remote settings in Ethiopia where information about the livestock disease is not well documented. Hence this study was conducted to determine the causative agents and their antimicrobial susceptibility pattern of bacterial Pasteurella isolates among pneumonic ovine in Haramaya district, Eastern Hararghe, Ethiopia. RESULTS: Out of 256 samples examined, Pasteurella was isolated in 64 (25%), of which 38 (59.4%) were from lungs and 26 (40.6%) were from nasal cavities. 87.5% of the isolates were Mannheimia haemolytica and 12.5% were Pasteurella multocida. All of the isolates from the lungs were Mannheimia haemolytica whereas 69% of the isolates from nasals cavities were Mannheimia haemolytica. Age and body temperature were significantly associated with Pasteurella isolates from clinic (P < 0.05). Despite diverse in the site of origins, the isolates exhibited uniformity in sensitivity to a majority of the antibacterial agents. The most effective drug was Cholramphenicol (100%) followed by Sulfamethoxazole (89.1%) and Tetracycline (84.4%). Both species were completely resistant to Gentamycin and Vancomycin. CONCLUSION: Mannheimia haemolytica is the most common cause of ovine pneumonic pasteurellosis in the study area. The isolates were susceptible to limited antimicrobial agents. Therefore, the antimicrobial susceptibility test should be conducted before treatment, except for critical cases.

Pasteurella canis and Granulicatella adiacens conjunctivitis outbreak resistant to empirical treatment in a child welfare agency.

PURPOSE: To investigate pathogens associated with bacterial conjunctivitis resistant to the empirical treatment and their antibiotic resistance in a child welfare agency. METHODS: Twenty-eight eyes in 14 children with a median age of 3 months with conjunctivitis resistant to the empirical treatment were included in this study. Samples were taken three times from the inferior fornix in both eyes using cotton swabs, cultured onto chocolate and blood agar, and prepared for Gram staining. Antibiograms were evaluated according to the Clinical and Laboratory Standards Institute criteria by disc diffusion method. RESULTS: The conjunctival culture positivity rate was 35.7% in eyes with conjunctivitis resistant to the empirical treatment. The most common isolated bacteria were Pasteurella canis (25%), penicillin-nonsusceptible Streptococcus pneumoniae (7.1%), and Granulicatella adiacens (3.6%). According to culture results, ophthalmic solutions of vancomycin (50 mg/mL) or gentamicin (30 mg/mL) were applied in eyes with positive conjunctival culture. Previously applied multiple treatments were stopped in eyes with negative conjunctival culture. All eyes improved clinically during follow-up. CONCLUSION: Because unusual pathogens may cause a conjunctivitis outbreak, physicians should not insist on empirical treatment. Taking conjunctival culture and antibiotic switching according to antibiogram may be helpful.

Detection of toxigenic Pasteurella multocida infections in swine herds by assaying antibodies in sow colostrum.

Toxigenic Pasteurella multocida is the causative agent of progressive atrophic rhinitis (PAR), a serious respiratory infection of swine. Diagnosis of the disease has hitherto been based on clinical signs, pathologic findings, and subsequent isolation of the agent. The best Finnish pig breeding herds participating in the Finnish Pig Health Scheme have been surveyed for PAR since 1963, and the disease has been eradicated from these herds. In this study, a total of 5,650 colostrum samples from 188 Finnish Pig Health Scheme herds were analyzed with a new serologic screening method: an enzyme-linked immunosorbent assay (ELISA) able to detect antibodies to the toxin of P. multocida (PMT). Although the herds had been continuously controlled for PAR, 1 herd with PMT antibodies was found. The positive reactions in the ELISA were confirmed by isolating the causative organism. The origin of the infection also appeared to be obvious. The serologic ELISA is a suitable method for the detection and screening of toxigenic P. multocida-infected pig herds.