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Poultry is a major Salmonella reservoir, but conventional culture-based methods typically identify the most abundant serovars while those less abundant remain undetected. Choice of enrichment procedure also introduces bias, and for broiler carcasses, a 1-min rinse before preenrichment is insufficient to release all Salmonella present. The inability to assess serovar diversity means that serovars more often associated with human illness may be masked by more abundant Salmonella. CRISPR-SeroSeq (serotyping by sequencing clustered regularly interspaced short palindromic repeats), an amplicon-based, next-generation sequencing tool, allows detection of multiple serovars and maps the relative serovar frequencies in a sample. To address the preceding limitations, CRISPR-SeroSeq was used on broiler carcasses collected prechilled at a commercial plant. Standard carcass rinse aliquot preenrichments and whole carcass preenrichments that were enriched in Rappaport-Vassiliadis (RV) and tetrathionate (TT) broths were compared. On average, five serovars were observed per carcass, including nine on one carcass. CRISPR-SeroSeq detected serovars comprising as little as 0.005% of the population. CRISPR-SeroSeq data matched (28 of 32) standard culture analysis for abundant serovars. Salmonella serovars Kentucky, Typhimurium, and Schwarzengrund were found on each carcass. Overall, serovar diversity was higher in whole carcass preenrichments that were enriched in RV (P < 0.05). Serovar Schwarzengrund was present at higher frequencies in whole carcass preenrichments compared with rinse aliquot preenrichments (t test, P < 0.05), suggesting it adheres more strongly to the carcass. Salmonella serovar Enteritidis was enriched eightfold more in TT than in RV, and serovars Schwarzengrund and Reading were preferentially enriched in RV. Comparison of preenriched and enriched samples suggests that selective enrichment in RV or TT was inhibitory to some serovars. This article addresses limitations of Salmonella surveillance protocols and provides information related to Salmonella population dynamics. CRISPR-SeroSeq identified between four and nine Salmonella serovars per broiler carcass at slaughter. Whole carcass preenrichment released more serovars than standard rinse aliquot preenrichment. Salmonella serovar profiles are influenced by preenrichment and selective enrichment procedures. Salmonella Enteritidis is selected in TT broth; Salmonella Schwarzengrund is selected in RV broth. [ABSTRACT FROM AUTHOR]

Abstract Leptospirosis is one of the most widespread zoonotic diseases and despite extensive research, there is still a paucity of information regarding this disease in cats. The aim of this study was to investigate the prevalence of leptospirosis among the shelter cat population in Malaysia and to determine the most common infective Leptospira serogroups among them. Blood samples were collected from a total of 110 cats from 4 different shelters. The sampled cats appeared healthy, with minimal evidence of feline upper respiratory disease. The Microscopic Agglutination Test was used to detect anti- Leptospira antibodies against 20 pathogenic serovars. Based on a cut-off antibody titer of ≥1:100, 20 of 110 sheltered cats, showed presence of anti- Leptospira antibodies against at least 1 serovar. The serodetection of leptospirosis was 18.18% (95% confidence interval 12.09-26.42). The most commonly detected serogroups were Bataviae, Javanica, and Ballum, with antibody titers ranging from 1:100 to 1:1600. Knowledge of the predominant infective serovars in hosts worldwide and regionally is imperative for understanding the epidemiology of this zoonotic disease. Serosurveillance is the first step in this process. Further studies are warranted for investigation of urinary shedding in naturally infected cats with leptospirosis, using Polymerase chain reaction (PCR) and organism isolation followed by serovars identification. [ABSTRACT FROM AUTHOR]

Problems with serological cross-reactivity have led to development of a number of PCRs (individual and multiplex) for molecular typing of Actinobacillus pleuropneumoniae , the causative agent of porcine pleuropneumonia. Most of these assays were developed for detection of specific amplicons within capsule biosynthetic genes before the availability of complete sequences for the different serovars. Here we describe comparative analysis of the complete capsular loci for all 18 serovars of A. pleuropneumoniae , and development of two multiplex PCRs for comprehensive capsule typing of this important pig pathogen. [ABSTRACT FROM AUTHOR]

This systematic review summarises the data published on the Leptospira seroprevalence, serovar diversity and distribution among animal species in the Caribbean region. Following Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, and checklist, relevant articles were identified and data were extracted and recorded. The review provided Leptospira seroprevalence data from 16 Caribbean islands (Barbados, Trinidad, Grenada, Puerto Rico, Saint Croix, St. Kitts and Nevis, Jamaica, Antigua, Carriacou, Dominica, Guadalupe, Martinique, Monserrat, St. Lucia, St. Maarten, and St. Vincent) in a variety of animal species. Reviewing the literature highlighted the limited amount of data available from limited number of islands. Many of the studies conducted have recorded seroprevalences based on variable and small samples sizes. Besides, serovar panels used for MAT were not consistent between studies. The review indicates that the Leptospira exposure in a given geographic location may change with time and climatic and environmental conditions, and highlights the need to conduct continual surveillance in tropical countries where the climate supports the survival of Leptospira in the environment. Specific attention must be given to standardization of MAT panels and protocols and providing training across laboratories involved in testing. Further, animal and environment testing to isolate and identify circulating Leptospira spp. in a geographic region must actively be pursued. This knowledge is important to implement geographically specific control programs, as risk factors of Leptospira transmission is favoured by various factors such as change in climatic conditions, urbanization, encroachment of wildlife inhabitation, import/export of animals, increase in adventure travel, and water related recreational activities. [ABSTRACT FROM AUTHOR]

A multiplex PCR was developed to identify the two most common serovars of Salmonella causing foodborne illness in Canada, namely, serovars Enteritidis and Typhimurium. The PCR was designed to amplify DNA fragments from four Salmonella genes, namely, invA gene (211-bp fragment), iroB gene (309-bp fragment), Typhimurium STM 4497 (523-bp fragment), and Enteritidis SE147228 (612-bp fragment). In addition, a 1,026-bp ribosomal DNA (rDNA) fragment universally present in bacterial species was included in the assay as an internal control fragment. The detection rate of the PCR was 100% among Salmonella Enteritidis (n = 92) and Salmonella Typhimurium (n = 33) isolates. All tested Salmonella isolates (n = 194) were successfully identified based on the amplification of at least one Salmonella -specific DNA fragment. None of the four Salmonella DNA amplicons were detected in any of the non- Salmonella isolates (n = 126), indicating an exclusivity rate of 100%. When applied to crude extracts of 2,001 field isolates of Salmonella obtained during the course of a national microbiological baseline study in broiler chickens and chicken products sampled from abattoir and retail outlets, 163 isolates, or 8.1%, tested positive for Salmonella Enteritidis and another 80 isolates, or 4.0%, tested as Salmonella Typhimurium. All isolates identified by serological testing as Salmonella Enteritidis in the microbiological study were also identified by using the multiplex PCR. The new test can be used to identify or confirm pure isolates of the two serovars and is also amenable for integration into existing culture procedures for accurate detection of Salmonella colonies. [ABSTRACT FROM AUTHOR]

Salmonella species are Gram-negative bacteria with more than 2600 serovars. Among these serovars, many are associated with various diseases in livestock and humans. White Kauffman Le-Minor (WKL) serotyping scheme applies specific serum to determine the serovars of Salmonella. Recent studies have applied molecular methods for serovar predictions. These methods include PCR, hybridization and sequence data to detect/predict serovar-specific genetic elements. Among these, PCR is a robust method if the unique genetic element is already known. Within this context, also involving novel primers, two multiplex PCR assays were standardized to detect six important Salmonella serovars viz. Typhimurium, Enteritidis, Kentucky, Infantis, Virchow and Gallinarum associated with poultry in India. The developed PCR assays showed targeted serovar specificity. Serial dilution experiments of both kit-based and crude lysate DNA preparations indicated similar applicability of both methods for testing from pure cultures. Further the developed assays were validated with 25 recent field isolates to confirm the applicability in routine diagnosis. The PCR assay could predict all the targeted serovars (17/25) with 100% specificity (CI-95%; 0.63–1). Molecular serotyping can reduce the number of serum used in comparison to the conventional serotyping which involves more random application of serum. [Display omitted] • Two multiplex PCR assays were developed to detect six important Salmonella serovars associated with poultry in India. • Developed molecular serotyping PCR assays showed high specificity for the targeted Salmonella serovars. • Detection limits were comparable for both kit-based and crude lysate DNA preparations during multiplexing. • PCR assays could detect targeted serovars when applied to recent field strains indicating applicability in routine diagnosis. [ABSTRACT FROM AUTHOR]

This study aims to determine the prevalence of fluoroquinolone resistance of Ureaplasma biovars and serovars isolated from urogenital clinical samples and determine the underlying molecular mechanism for quinolone resistance for all resistant isolates. Of 105 samples confirmed as positive for U . urealyticum / U . parvum , 85 were resistant to quinolones by the Mycoplasma–IST2 kit. However, only 43 out of 85 quinolone resistant isolates had amino acid substitutions in GyrA, GyrB, ParC and ParE proteins underlining that this assay have mis-identified as fluoroquinolone resistant 42 isolates. The known ParC E87K and ParC S83L mutations were found in 1 and 10 isolates, respectively. An original mutation of ureaplasmal ParC (E87Q, 1 isolate) was found. Furthermore, we found a ParE R448K mutation in one isolate, already described. Among the additional alterations detected, the most prevalent mutation found was L176F in GyrA protein in 18 isolates with single infection and in 3 isolates with mixed ureaplasma infections. Mutations in GyrB (E502Q, 4 isolates), ParE (Q412K, Q412P, Q412T, 3 independent isolates), whose role is unknown, were also found. Other sporadic mutations in the four genes were identified. This investigation is the result of monitoring the data for molecular fluoroquinone resistance in Ureaplasma spp. in Italy. Resulting that this acquired resistance is high and that continued local epidemiological studies are essential to monitor and document their antimicrobial resistance trends. [ABSTRACT FROM AUTHOR]

Most leptospiral infections in horses are asymptomatic; however, acute disease manifestations as well as reproductive failure and recurrent uveitis have been reported. In South Africa, the epidemiology of the disease in horses is not well documented. A serosurvey to determine what serovars were present in horses from Gauteng, KwaZulu-Natal and Western Cape Provinces and to get an estimate of the seroprevalence of leptospirosis was carried out from January 2013 until April 2014 with the assistance of four large equine hospitals located in these provinces. Furthermore, associations between potential risk factors and both seropositive horses to the predominant serovar Bratislava and to Leptospira spp. were statistically evaluated using univariate analysis and multivariable logistic regression models. A total of 663 horse sera were collected and tested against a panel of 24 leptospiral serovars using the microscopic agglutination test. The most predominant serovars in Gauteng were Bratislava [32%, 95% CI: 29–35%]; Djasiman [10.4%, 95% CI: 8–12%] and Arborea [8.9%, 95% CI: 7–11%], in the Western Cape Province, Bratislava [27.35%, 95% CI: 23–32]; Djasiman [15.4%, 95% CI: 12–19%] and Arborea [14.5%, 95% CI: 11–18%] and in KwaZulu-Natal, Bratislava [39.4%, 95% CI: 34–44%]; Arborea [9.6%, 95% CI: 7–13%]; and Tarassovi [7.7%, 95% CI: 5–10%] respectively. Twenty one serovars representing 17 serogroups were detected with serovar Bratislava being the most serodominant. The apparent prevalence to one or more serovars of Leptospira spp. at a serum dilution of 1:100 in Gauteng, KwaZulu-Natal and Western Cape Provinces were 49%; 37% and 32% respectively. The true prevalence was calculated for each province taking into account the clustering effect during the sampling and was found to be between 24 and 74% in Gauteng; 26–39% in the Western Cape and 20–54% in KwaZulu-Natal. Nooitgedacht (South African horse breed) horses were found to be at greater risk of being seropositive to both serovar Bratislava (OR = 5.08) and Leptospira spp. (OR = 6.3). Similarly, horses residing on properties with forestry in the vicinity were found to be at greater risk of being seropositive to both serovar Bratislava (OR = 9.3) and Leptospira spp. (OR = 5.2). This study has shown that a high proportion of horses in South Africa are exposed to a wide range of serovars, inferring a complex epidemiology. It also describes for the first time new serovars of Leptospira in South African horses that have not previously been reported. [ABSTRACT FROM AUTHOR]

Increases in foodborne disease outbreaks associated with fresh produce have necessitated the need to identify potential sources of microbial contamination in produce and agricultural environments. The present study evaluated Salmonella prevalence and serovar diversity in fruit (225), water (140) and surface (126) samples, from three commercial farms and associated packhouses, located in different farming regions in South Africa. Fruit and water samples were collected from both orchards and packhouses, while surface samples were collected from conveyer belts and hands of packhouse employees. Salmonella was detected in 26 of the 491 (5.3%) samples. Environmental samples (water and surfaces) recorded a slightly higher proportion (3.1%; 15/491) of positive samples compared to fruit samples (2.2%; 11/491). Salmonella was not detected on employee hands and river water samples. A total of 263 Salmonella isolates were obtained from the 26 positive samples by standard culture methods, preliminarily identified through matrix-assisted laser desorption ionisation-time of flight mass spectroscopy (MALDI-TOF MS) and API 20E, and confirmed by invA gene. Of the 39 representative isolates serotyped the serovars Muenchen (33.3%), Typhimurium (30.8%), Heidelberg (20.5%), Bsilla (7.7%), Salmonella subspecies IIb: 17: r: z (5.1%) and one untypable strain were identified. Most samples had multiple serovars with orchard water form one site recording the highest serovar diversity (4 serovars). Our findings show the potential of agricultural fruit production environments to act as reservoirs of clinically important Salmonella serovars. [ABSTRACT FROM AUTHOR]

Aquaculture products can become sources of Salmonella by exposure to contaminated water or through processing practices, thus representing a public health hazard. A study was conducted on Salmonella contamination in aquaculture products sampled from marketplaces and retailers in Shanghai, China. A total of 730 samples (including fish, shellfish, bullfrog, clam, shrimp and others) were obtained from 2006 to 2011. Among them, 217 (29.7%) were positive for Salmonella . Thirty-eight serovars were identified in the 217 Salmonella isolates. The most prevalent were Salmonella Aberdeen (18.4%), S. Wandsworth (12.0%), S . Thompson (9.2%), S . Singapore (5.5%), S . Stanley (4.6%), S . Schwarzengrund (4.6%), S . Hvittingfoss (4.1%) and S . Typhimurium (4.1%). Many resistant isolates were detected, with 69.6% resistant to at least one antimicrobial drug. We observed high resistance to sulfonamides (56.5%), tetracycline (34.1%), streptomycin (28.6%), ampicillin (23.5%) and nalidixic acid (21.2%). Lower levels of resistance were found for gentamicin (3.2%), ciprofloxacin (2.3%), ceftiofur (1.3%), cefotaxime (0.9%), ceftazidime (0.5%) and cefepime (0.5%). A total of 43.3% of the Salmonella isolates were multidrug-resistant and 44 different resistance patterns were found. This study provided data on the prevalence, serovars and antimicrobial resistance of Salmonella from retail aquaculture products in Shanghai, and indicated the need for monitoring programs for microbiologic safety in such projects and for more prudent drug use in aquaculture production in order to reduce the risk of development and spread of antimicrobial resistance. [ABSTRACT FROM AUTHOR]

This supplement (no. 48) of the White–Kauffmann–Le Minor scheme reports on the characterization of 63 new Salmonella serovars and 25 new variants of previously described Salmonella serovars recognized by the WHO Collaborating Centre for Reference and Research on Salmonella between 2008 and 2010. Forty-four new serovars were assigned to Salmonella enterica subspecies enterica , 12 to subspecies salamae , two to subspecies arizonae , two to subspecies diarizonae and three to subspecies houtenae . All these new serovars or new variants are described with their multilocus sequence type. [ABSTRACT FROM AUTHOR]

Abstract: In this work the prevalence and serovar diversity of Salmonella in various food products including non-thermally processed food and ready-to-eat (RTE) food in Estonia in 2008–2012 are summarized. The findings demonstrate that the overall prevalence of Salmonella in these food categories was low. A total of 260 (0.54%) of 47,927 food samples were found to be positive for Salmonella, the overall prevalence in non-thermally processed food was 0.81% (256/31,576) and in RTE products only 0.02% (4/16,351). Salmonella was most often isolated from raw eggs and products thereof (2.17%, 5/230), followed by raw meat products (0.95%, 207/21,723), RTE mayonnaises (0.90%, 2/221) and raw meat (0.89%, 38/4252). In the raw meat category, Salmonella was most frequently isolated from turkey meat (6.96%, 11 positive samples out of 158), broiler chicken meat (4.00%, 7/175) and from layer hen meat (2.22%, 11/496). Salmonella was isolated in lesser extent from meat preparations (1.91%, 82/4292), minced meat and mechanically separated meat products (0.97%, 100/10,344) and from raw sausages (0.35%, 25/7087). Altogether 24 different serovars were identified among the 260 Salmonella positive samples. Salmonella Typhimurium was the most frequent serovar (26.90% of the positive samples) and it was isolated most commonly in raw food products. The next most frequent serovars were Salmonella Derby (17.50%), Salmonella Enteritidis (8.37%) and Salmonella Newport (7.57%). The only serovars isolated from the Salmonella positive RTE food samples were Salmonella Infantis (two isolates) and S. Enteritidis (two isolates). [Copyright &y& Elsevier]

Abstract: The aims of this study were to investigate the serotype distribution, genetic relationships and antibiotic resistance of Salmonella from food-producing animals in Shandong province of China in 2009 and 2012. A total of 362 out of 1825 samples from chickens, 53 out of 445 samples from ducks, and 50 out of 692 samples from pigs were positive for Salmonella. Isolates were subjected to serotyping, antibiotic susceptibility testing (15 antibiotics) and pulsed-field gel electrophoresis (PFGE). The most common serotypes recovered in the chicken samples were Enteritidis (n=294, 81.2%) and Indiana (n=45, 12.4%). For ducks, Cremieu (n=25, 47.2%), Indiana (n=13, 24.5%) and Typhimurium (n=9, 17%) were frequently isolated. In the pig samples, Derby (n=29, 58%), Typhimurium (n=9, 18%), and Enteritidis (n=6, 12%) were the most common serovars. PFGE results indicated that clonal dissemination of each serovar was prevalent, and that the Salmonella found on the poultry carcasses was caused by cross-contamination in the abattoirs. More than 99% of the Salmonella isolates collected were resistant to at least one antibiotic. The Salmonella resistance rates for 15 antibiotics in 2012 were significantly higher than those in 2009. In 2012, the highest resistance was to nalidixic acid (95.9%), followed by sulphafurazole (78.2%) and ampicillin (72.3%); the lowest levels of resistance were to kanamycin (40.1%) and amikacin (38.7%). Additionally, 41.5% and 42.2% of the Salmonella were resistant to ciprofloxacin and ceftiofur, respectively. Noticeably, 25% of the serovar Enteritidis and all of the serovar Indiana were resistant to at least 10 antibiotics in 2012. The increasing trend of antibiotic resistance in Shandong province indicates the need for more careful use of antibiotics. [Copyright &y& Elsevier]

Salmonella is an essential food-borne pathogenic microorganism. Humans could get infected by consuming of Salmonella -contaminated foods, especially contaminated meat. In this study, a total of 580 retail meat samples (280 pork, 240 chicken, and 60 goose) were collected from slaughterhouses in Hangzhou to determine the prevalence and antimicrobial susceptibility patterns of Salmonella. Isolates were characterized by serotyping, PFGE (Pulsed-field gel electrophoresis), Polymerase chain reaction (PCR), and antibiotic susceptibility testing. The rates of Salmonella -positive pork, chicken, and goose samples were 21.1% (n = 59), 10.4% (n = 25) and 10.0% (n = 6), respectively. The prevalence of Salmonella was 15.5% in slaughterhouses. Thirteen different Salmonella serovars were identified, and 6 isolates could not be identified. The most commonly prevalent serovars are Salmonella Rissen (S. Rissen) (n = 20, 22.2%), S. Derby (n = 16, 17.8%) and S. Typhimurium (n = 12, 13.3%). The detection rate of the remaining serovars ranged from 1.1%–11.11%. All Derby, Corvallis, and Kentucky strains were from pork. Seventy-two isolates (80.0%) showed drug resistance (DR) to at least one antibiotics, 19 (21.1%) were multi-drug resistant strains, 2 (2.2%) showed seven or more. The detection rate of Trimethoprim/Sulfamethoxazole-resistance (70.0%) was highest, followed by Ampicillin (55.6%). Salmonella resistance was found related to serovar and origin. The positive rates of DR gene sul1 , sul2, sul3, class I integrons and bla TEM were 92.2%, 95.6%, 86.7%, 83.3% and 62.2%, respectively. Fifty-seven different PFGE patterns and 7 main clusters were obtained. This study revealed the high positive rates of Salmonella resistance and related DR genes, especially for Sulfamethoxazole-resistance and its related gene. • The prevalence of Salmonella and MDR isolates was 15.5% and 21.1%, respectively. • The positive rates of partial resistance (0–70%) and DR genes (62.2–95.6%) were high. • The resistance of Salmonella isolates was related to serovar and origin. [ABSTRACT FROM AUTHOR]

Abstract: A preliminary epidemiological study of Salmonella contamination in laying-hen flocks was carried out in the regions of Annaba and Eltarf, Algeria, from March to October 2008 and March to November 2009. Our objectives were (i) to estimate the prevalence of infection by Salmonella spp. in seven pooled samples during the hens'' laying period (ii) to identify the serotypes and antimicrobial resistance phenotypes of isolates, and (iii) to characterize the factors that may be related to Salmonella contamination in Algerian henhouses. For this purpose, 18 out of 22 operational laying-hen houses were sampled one to three times during these periods: once at the start of laying (pullets aged 22–31weeks), once in the middle of laying (47–60week) and once at the end of laying prior to depopulation (70–86week). The flocks''Salmonella status was assessed by collecting 2754 environmental samples that were analyzed according to the ISO 6579 method. The antibiotic resistance of Salmonella strains was tested as per the guidelines of the Clinical and Laboratory Standards Institute (CLSI). The relationship between each potential risk factor and the Salmonella status of laying-hen flocks was evaluated by calculating the relative risk with 95% confidence intervals. Eight flocks tested positive for Salmonella spp., with a higher prevalence at the end of laying than at either the beginning or middle. Only 19 isolates were recovered from the 2754 samples analyzed and nine different serotypes identified. S. enteritidis (n=4) was the most prevalent serovar, along with S. Kentucky and S. Hadar (n=3), followed by S. Heidelberg, S. Manhattan and S. Virchow (n=2), whereas S. Dublin, S. Typhimurium and S. Albany were found only once. Thirteen isolates were resistant to at least one antimicrobial agent. Of these, six were resistant to at least three different antimicrobial classes. Salmonella serovar Kentucky isolates were resistant to fluoroquinolones with ciprofloxacin MIC≥8mg/L. Six risk indicators were identified as potentially related to the Salmonella status of layer houses. [Copyright &y& Elsevier]

Abstract: Salmonella is a leading cause of foodborne diseases and the role of ready-to-eat products including plant-derived food is increasingly recognized. The present survey reviewed recent literature on Salmonella-related outbreaks caused by spices and herbs and on the occurrence of Salmonella in these food matrices. Spices and herbs contaminated with Salmonella were responsible for a variety of foodborne outbreaks in Europe and North America. Identified serovars did often not belong to those predominating in human illness. Moreover, in different survey studies, Salmonella belonging to a broad diversity of serovars were found in a variety of spices and herbs. The proportion of Salmonella-positive samples ranged from 0% to 8.4%, albeit detection rates were rather low in most studies. Higher prevalence rates were often obtained with regard to a specific spice or herb type. Due to high desiccation tolerance, Salmonella can survive for an extended period of time in spices and dried herbs. Thus, by the use of untreated spices and herbs for production of foods not subjected to a heat treatment or for seasoning of ready-to-eat products, Salmonella might be introduced and in this way might pose a threat to consumers. [Copyright &y& Elsevier]

Abstract: The presence of Listeria in three milk processing environments as a potential source of milk contamination was assessed. Swab samples (n = 210) taken from milk processing plants were examined. Sample sites included the milk processing equipment, besides areas handling raw and pasteurized milk. The USDA Listeria-selective enrichment procedure was used to process the samples. Forty one (19.52%) Listeria isolates were recovered. The isolates were further subjected to biochemical and genotypic characterization. Out of 41 isolates, 16 (7.62%) were confirmed as Listeria monocytogenes, 2 (0.95%) as L. ivanovii, 19 (9.05%) as L. innocua. 1 (0.48%) as L. seeligeri and 3 (1.43%) as L. grayi. All the L. monocytogenes isolates were positive for the hlyA gene. PCR based serotyping revealed all L. monocytogenes to be of 1/2a, 1/2c, 3a and 3c serovar group. AscI and ApaI restriction analysis yielded four PFGE clusters for 16 L. monocytogenes isolates obtained from raw milk collector, milk silos, buttermilk mixer, cheese and other milk product processor. No predominant PFGE cluster was observed among these L. monocytogenes isolates. The main sources of L. monocytogenes were found to be raw milk collector and milk silos. In the present study L. monocytogenes was isolated from milk and milk products processing plants which could cross-contaminate the processed products and may possess a potential threat to public health. [Copyright &y& Elsevier]

Abstract: Prevention of Salmonella contamination of poultry products requires detailed knowledge of the main sources associated with its presence in the production system. The aims of this study were to determine the main sources of Salmonella contamination in broiler production during growing, to assess the risk factors for Salmonella contamination at the end of the rearing period and to determine the main serovars involved in broiler production systems in Eastern Spain. A total of 65 different broiler houses from different farms were sampled. Each house was sampled at different times during the rearing period. First, when the previous flock was taken to the slaughterhouse, samples of dust, surfaces and previous flock faeces were collected. After cleaning and disinfection (C&D), samples of dust and surfaces were also taken. On the first day of rearing, samples of water, bedding, farming boots, meconiums, delivery-box liners and feed were collected. During rearing, feed samples were taken directly from the truck and from feeders. On slaughter day, samples of dust, surfaces, water, feed and faeces were also collected. Finally, two days after slaughter, carriers (rodents, flies and beetles) were trapped. All samples collected were analysed according to (Annex D) and positive samples were serotyped in accordance with Kauffman–White–Le–Minor technique. Our results showed that all different types of samples collected were contaminated with Salmonella (prevalence ranged between 1.5% and 38.6%). The most contaminated samples related with poultry production were: delivery-box liners (32.0%), faeces samples (31.2%), dust samples (25.0%), farming boots (19.7%) and feed from feeders (16.0%). However, the most important risk factors for Salmonella contamination of the flocks at the end of the rearing period were Salmonella status of the house after cleaning and disinfection, Salmonella status of day-old chick flocks and feed from feeders. Twenty-one different serovars were isolated from the samples analysed. The most prevalent were in decreasing order: Salmonella Enteritidis (52.9%), S. Hadar (17.8%), S. Virchow (8.9%) and S. Ohio (5.4%). The study suggested that there are many sources for Salmonella contamination and persistence in broiler production. Hence, the whole production chain needs to be controlled to eradicate the bacteria from primary production. [Copyright &y& Elsevier]

Abstract: Leptospirosis is a re-emerging disease of dogs in the United States (U.S.). This paper reports the findings of a retrospective study conducted to determine if seroreactivity to Leptospira microscopic agglutination test (MAT) among dogs in the U.S. clustered in space and time. The study utilized canine sera submitted to a commercial laboratory for leptospiral MAT from January 2000 through December 2007. There were 31,869 serum samples submitted by veterinarians from 3156 zip code locations across the U.S. Results of MAT were considered positive at titers of ≥1:1600. Spatial and spatial-temporal scan statistics were used to identify statistically significant clusters of seroreactivity to Leptospira (overall and individual serovars) using recorded test request dates and locations of the centroid of the zip code reported for each serum sample. There were 2469 positive MAT results with a titer ≥1:1600 to at least one of seven Leptospira serovars. Two relevant spatial clusters of 26.3 and 246.5km radius were identified (P =0.001). The primary cluster was located in the northeastern part of Illinois including Chicago and surrounding areas (232 [14.4%] of 1612 MAT positive; RR=1.95). The secondary cluster covered the central part of Texas (292 [12.62%] of 2314 MAT positive; RR=1.71). Eight space-time clusters of overall MAT positivity were identified (29–335km radius; P =0.001–0.048 and RR=3.98–24.69) that covered different geographic locations for different time points. Spatial and space-time clusters for individual serovars were also identified for six serovars: eight each of Grippotyphosa and Pomona, seven of Bratislava, five of Autumnalis, and three each of Icterohaemorrhagiae and Canicola. In conclusion Leptospira seropositivity in dogs tended to have distinctive clusters in space and space-time. Most of the space-time clusters of overall Leptospira MAT seropositivity were associated with cluster events for individual serovars. Further investigation is warranted to explain individual serovar clusters detected in this study, as a complex interaction of incidental host, environment and reservoir host may be responsible for the occurrence of these serovar clusters. [Copyright &y& Elsevier]

Abstract: The aim of the present study was to determine the antimicrobial susceptibility of Haemophilus parasuis in China and to investigate possible correlations between antimicrobial resistance and serovars or virulence. The susceptibility of 110 clinical isolates to 22 antimicrobial agents was determined by an agar dilution method. Except 28 isolates (25.5%) were non-typable, the isolates comprising thirteen serovars (1–5, 7–10, and 12–15), with the most prevalent were serovars 4 (14.5%), 5 (26.4%), 12 (9.1%) and 13 (10.9%). All isolates were susceptible to cefotaxime, ceftiofur, azithromycin, chloramphenicol, florfenicol and tilmicosin, and most of them were susceptible to penicillin, ampicillin, cefaclor, levofloxacin, ciprofloxacin, erythromycin, tetracycline, gentamicin, spectinomycin and tiamulin; however, a high level of resistance was encountered for enrofloxacin (70.9%) and trimethoprim/sulphamethoxazole (44.5%). There were 32 antimicrobial antibiograms observed, with 23.6% of the isolates resistant to more than 3 antimicrobial agents. Antimicrobial resistance was observed in every serovar included in this study, but no statistically significant association was observed between the antimicrobial resistance and the serovars or virulence of H. parasuis. [Copyright &y& Elsevier]

Abstract: This supplement reports the characterization of 70 new Salmonella serovars recognized between 2003 and 2007 by the WHO Collaborating Center for Reference and Research on Salmonella: 44 were assigned to Salmonella enterica subspecies enterica, 11 to subspecies salamae, 5 to subspecies arizonae, 8 to subspecies diarizonae, one to subspecies houtenae and one to Salmonella bongori. One new serovar, Mygdal, displayed a new H factor, H:z91. [Copyright &y& Elsevier]

Abstract: Multiplex-PCR (MPCR) serogrouping and pulsed-field gel electrophoresis (PFGE) subtyping analysis are currently used by several public and private laboratories for the characterization of Listeria monocytogenes. In this study a set of 80 L. monocytogenes isolates belonging to the twelve serovars was used to investigate (i) the typeability of the rare serovars, (ii) the ability of PFGE analysis with ApaI and AscI to differentiate serovars within MPCR serogroups and (iii) the association of molecular types with the specific source or geographical origin of the isolates. With the exception of three isolates (rare serovars 4a and 4c) that were not amenable to restriction with ApaI, all the other analyzed isolates were subtyped by both enzymes. PFGE discriminated the 80 isolates into 62 combined ApaI and AscI PFGE patterns (pulsotypes), but could not differentiate serovars within MPCR serogroups, in which isolates from different serovars displaying the same pulsotype were found. Clustering analysis suggests that for some pulsotypes grouping according to Portuguese origin or source can be suggested. On the other hand, some L. monocytogenes clones are widely distributed. Two pulsotypes from Portuguese human isolates were identical to the ones displayed by human outbreak clones in the UK and in the USA and Switzerland, respectively, although they were not temporally matched. Computer-assisted data analysis of large and diverse PFGE type databases will improve the correct interpretation of subtyping data in epidemiological studies and in tracing routes and sources of contamination in the food industry. [Copyright &y& Elsevier]

Abstract: From September 2002 to December 2004, a total of 281 strains of Haemophilus parasuis were isolated from 17 provinces of China. All these isolates were serotyped by both the gel diffusion (GD) and the indirect haemagglutination (IHA) tests. By combining the GD and IHA results, serovar 4 (24.2%) and serovar 5 (19.2%) were the most prevalent serovars, followed by serovars 13 (12.5%), 14 (7.1%) and 12 (6.8%), while 12.1% of the isolates could not be assigned to a serovar (nontypable). A comparison of the number of isolates obtained from the respiratory tract of swine without polyserositis with those obtained from swine with polyserositis revealed an increased frequency of serovar 4 and a significantly decreased frequency of serovar 13 among isolates from the respiratory tract of swine without polyserositis, whereas the frequency of isolation of serovars 5, 12, 14 and nontypable from swine with or without polyserositis were similar. Co-infection of H. parasuis and other bacterial agents was studied in 183 cases examined from June 2003 to December 2004. Streptococcus suis (30.6%; 56), Escherichia coli (21.9%; 40), Bordetella bronchiseptica (21.3%; 39) and Pasteurella multocida (14.2%; 26) were the bacterial agents frequently co-isolated with H. parasuis in China. [Copyright &y& Elsevier]

Abstract: The aim of this study was to determine the farm prevalence of Salmonella in 90 Alberta finishing swine farms over a 5-month period, to evaluate Salmonella distribution in the farm environment and to describe Salmonella serovar diversity on these farms. Ten veterinary practitioners selected 90 Alberta swine farms based on an annual production of ≥2000 market pigs per farm and the willingness of the producers to participate in the study. Between May and September 2000, twenty samples were collected from finishing swine and the environment of each farm. The annual production of selected farms represented approximately 25% of the market swine production in Alberta. Participating farms were geographically representative of major swine production areas in Alberta. Sixty (66.7%) farms had at least one Salmonella-positive sample, with confidence interval (CI) of 57.1–77.2%. Salmonella were detected in 14.3% of fecal and 20.1% of environmental samples. The number of Salmonella-positive samples per farm ranged from 1 to 19. Among environmental samples, Salmonella were most frequently recovered from boots (38.6%) and the main drain (31.8%). Twenty-two serovars were detected on the 60 Salmonella-positive farms. Serovars Typhimurium (78 isolates), Derby (71 isolates) and Infantis (47 isolates) were the most common. A single serovar was detected on 58 farms, while 2, 3 and >3 serovars were detected on 15, 10 and 7 farms, respectively. The Salmonella farm status changed frequently over the 5-month period indicating the dynamic nature of Salmonella infections on these farms. [Copyright &y& Elsevier]

Abstract: The study objective was to describe and evaluate antimicrobial resistance profiles in Salmonella isolated from Alberta swine finishing farms. Salmonella isolates (n=322) were obtained from 192 fecal and 84 environmental samples of the 60 Salmonella-positive swine finishing farms. Isolates were classified susceptible, intermediate or resistant based on NCCLS guidelines. More than half of the isolates (53.4%) were susceptible to all of the 18 antimicrobials in the testing panel. No resistance was observed to amikacin, amoxicillin/clavulanic acid, cefoxitin, ceftiofur, ceftriaxone, cephalothin, ciprofloxacin, imipenem or nalidixic acid. Less than 1% of isolates were resistant to apramycin, gentamicin and trimethoprim/sulfamethoxazole. Higher frequencies of resistance were observed for chloramphenicol (4.7%), ampicillin (7.8%), kanamycin (11.8%), sulfamethoxazole (21.1%), streptomycin (25.5%) and tetracycline (38.8%). Eleven Salmonella serovars had isolates with resistance to ≥3 antimicrobials. The most frequently resistant serovar was Salmonella Derby, with 27 (38.0%) isolates resistant to ≥3 antimicrobials, including resistance to five and six antimicrobials. An absence of resistance to cephalosporins and fluoroquniolones and a low proportion of isolates resistant to amikacin, amoxicillin/clavulanic acid, apramycin, gentamicin and trimethoprim/sulfamethoxazole are encouraging findings from public health and animal health perspectives. Frequent resistance observed for ampicillin, kanamycin, sulfamethoxazole, streptomycin and tetracycline, antimicrobials commonly used in veterinary medicine for decades, indicates an urgent need to utilize these antimicrobials more prudently if their benefits are to be preserved. [Copyright &y& Elsevier]

Glaesserella parasuis consists of 15 serovars with some of them highly virulent and some of them avirulent. As killed vaccines do not provide crossprotection across serovars, serotyping is of importance. Serotyping, previously done by gel diffusion, is now done by multiplex PCR followed by electrophoresis. Accurately differentiating 15 serovars by electrophoresis is problematic. To overcome this problem, a Luminex microbead-based multiplex assay was used to differentiate the serovars. The assay consisted of a multiplex PCR assay followed by hybridisation to microbeads which were then analysed on a Luminex machine. The newly developed assay was compared to the multiplex serotyping PCR and the gel diffusion/indirect haemagglutination assay (GD/IHA). The microbead-based assay worked very well for the 15 reference strains but when used on the 74 Australian field strains displayed some problems. The main problems were with the eight out of nine serovar 4 field isolates and the five serovar 7 and three serovar 14 field isolates. While the microbead-based assay could differentiate between the serovar 5 and 12 reference strains, which the serovar multiplex PCR could not, all four field isolates identified by GD/IHA as serovar 12 were identified as serovar 5 by the microbead-based assay. Serovar 4 has been noted to have a high diversity especially among strains from different countries. Our work clearly shows that the diversity of strains at both the national and the international level has to be taken into account when developing diagnostic assays. • Development of a microbead-based assay for serotyping the 15 serovars of Glaesserella parasuis. • Works well for reference strains from Germany, Japan, Sweden, Switzerland and USA. • Genetic variation in Australian isolates resulted in cross-reactions and false positive and negative results. • Before the development of a gene based assay the genetic variability of a species needs to be fully explored. [ABSTRACT FROM AUTHOR]

The prevalence of Salmonella spp. infection was determined in 67 free-range pig herds in southern Spain. Microbiological assessment was performed on ileocolic lymph nodes collected at slaughter according to ISO 6579:2002 procedures. Overall, 33% of herds were infected and the prevalence of infection was 5.3% Salmonella spp. serovars most frequently isolated were Anatum and Typhimurium, although uncommon serovars such as Hessarek and Mikawasima were also detected. Isolates were tested against 16 antimi-crobial agents and exhibited resistance to streptomycin (46%), tetracycline (30%), sulphonamides (25g) and ampicillin (23%) by the break-point method. Multi-drug resistance, defined as resistance to ≥4 anti-microbials, was 36% [ABSTRACT FROM AUTHOR]

Abstract: The phage typing of 3900 isolates of Salmonella Enteritidis and 1741 isolates of Salmonella Typhimurium has been carried out in the period 1995–2009. Among Salmonella Enteritidis in individual years, the most prevalent phage type (PT) was 8. The most predominant PTs of Salmonella Typhimurium were DT104 and U302. [Copyright &y& Elsevier]

• Seroprevalence in southern Brazil was 45.9%. • Antibodies to 12 serovars of Leptospira spp. (9 serogroups) were found in the study region. • Reproductive disorders by Leptospira spp. it was not observed in horse. • There was a higher percentage of positives among animals older than 10 years. • Icterohaemorragiae serogroup were more prevalent. Leptospirosis in horses is often associated with reproductive disorders. In the southern states of Brazil, horses are used for various jobs and cultural practices; nevertheless, serological surveillance for Leptospira is rare. Therefore, the objective of this study was to determine the seroprevalence of Leptospira spp. in horses in southern Brazil, as well as to identify the risk factors for infection and its impacts on reproduction. We performed microscopic agglutination tests for 12 serovars that corresponding 9 serogroup (Sejroe, Icterohaemorrhagiae, Australis, Pyrogenes, Pomona, Canicola, Grippotyphosa, Tarassovi and Ballum) in 595 samples from 60 herds. A brief history was obtained to analyze risk factors for reproductive disorders. A total of 45.9% of the tested horses were seropositive, of which the most frequent serogroups were Icterohaemorrhagiae (Icterohaemorrhagiae and Copenhageni serovars) and Ballum (Ballum serovar). Simple infections were found in 45.4% of seropositive animals, while mixed infections occurred in 54.6% of horses. There was a correlation between seropositivity and age and sex, that is, seropositivity was more frequent in animals over 6 years old and in females. There was no correlation between seropositivity and reproductive disorders. We conclude that there is a high seroprevalence of Leptospira spp. in southern Brazil with predominance of Icterohaemorrhagiae serogroup, mainly in older animals. Location, breeds, contact with dogs or other domestic animals are not risk factors, whereas gender is a risk factor. Reproductive disorders are not due to leptospirosis in the study region. [ABSTRACT FROM AUTHOR]

Salmonella is a major cause of morbidity and mortality in humans worldwide, and the infection with multidrug-resistant strains can cause severe diseases. Many coastal cities around the world discharge their wastewaters into the marine environment. These wastewaters contain a variety of pathogenic microorganisms that may have a role in the contamination of this ecosystem and have potential risks for public health. Using an environmental approach, the present study investigated the presence of Salmonella in sediment and water samples collected from Port Blair Bays. In this environmental approach, the provided information about the diversity of the Salmonella serovars, antibiotic resistance and the prevalence of virulence factors in Salmonella , especially from the coastal waters of Port Blair Bays. The occurrence of Salmonellae was significantly higher in water column samples (2.9%) than in those taken from the marine sediments (0.7%). Of the 133 positive Salmonella strains, 22 different serovars were identified. Salmonella enterica serovar Senftenberg was the predominant serovar, being represented by 54 isolates (42.5%), followed by serovar Typhimurium (19 isolates [15%]) and serovar Agona (12 isolates [9.4%]). The presence of virulence genes (filC , sitC , hilA , invA , sipC , hilD , hilC , invF , invE , invH , sipF , aadA , pare , gyrA , spaP and parC) and susceptibility studies with 10 selected antibiotics were also performed. The results of this study revealed that all Salmonella isolates were positive for targeted virulence genes and were resistant to at least one antibiotic. Antibiotic susceptibility studies revealed the presence of multidrug resistant Salmonella strains in coastal water, which usually from land base sources end up in the marine environment and may pose a significant risk on public health. • Population density of Salmonella sp. was high in Phoenix Bay and Junglighat Bay stations of Port Blair • Salmonella enterica Typhimurium and Salmonella enterica Enteritidis are the predominant species. • Maximum antibiotic resistant strains were isolated form the Phoenix Bay. • The filC and aadA genes were recorded as the dominant biomarker determinant. • First report on the occurrence of multidrug resistant Salmonella serovars in Port Blair Bays [ABSTRACT FROM AUTHOR]

Raw vegetables have been associated with numerous foodborne Salmonella outbreaks; however, there is little epidemiological or molecular data on Salmonella contaminants of raw vegetables in China. Here, we investigated the prevalence and molecular characteristics of Salmonella isolates from raw vegetables in China. In total, 406 raw vegetable samples were collected covering most provincial capitals in China. The overall prevalence of Salmonella was 3.4% (14/406), with contamination levels of <1 MPN/g. Coriander (7.8%, n = 90) and lettuce (6.0%, n = 83) showed the highest contamination rates. Among the 31 Salmonella isolates recovered from the 14 positive samples, 14 different serovars and 15 multilocus sequence typing patterns were identified. All of the identified serovars have previously caused infections in humans, with several also linked to raw vegetable-associated disease outbreaks. Of the 15 non-duplicate isolates, 7 (46.7%) were resistant to at least one class of antibiotics and 4 (26.7%) were multidrug-resistant. The highest rate of resistance was observed for nalidixic acid (33.3%). This study provides a systematical surveillance on prevalence of Salmonella in Chinese raw vegetables, and suggests that the Salmonella contamination of fresh vegetables is a potential risk to public health when they are eaten raw. • A high prevalence of Salmonella contamination was observed in raw vegetables. • All Salmonella serovars identified in this study can cause human disease. • Most of the serovars are linked to raw vegetable-associated disease outbreaks. • Isolates from raw vegetables showed high rates of antimicrobial resistance. [ABSTRACT FROM AUTHOR]

• IPEC-1 cell line is a useful tool to compare serovars of Salmonella enterica. • Differences were identified between serovars regarding the immune responses induced. • There are variations in the percentages of adhesion and invasion amongst serovars. • Secreted protein effectors' repertoires amongst serovars could explain differences. Salmonella is a genus of Gram-negative bacteria in the Enterobacteriaceae family causing various illnesses. The ability of the different serovars of Salmonella enterica subsp. enterica to infect a host and to induce pathology relies in part on their cellular and molecular interactions with the intestinal epithelium. In the current study, an in vitro approach using non-polarized or polarized IPEC-1 porcine intestinal epithelial cells were used in order to assess the relation between adhesion, invasion, and induction of the immune response as a function of the serotype of Salmonella. Five serovars, Choleraesuis (host-adapted), Typhimurium (ubiquitous), Typhisuis (host-restricted), which are relevant for pig infection, and Dublin and Gallinarum, which are host-restricted or host-adapted, were studied. A strong variation was observed in the percentages of adhesion and invasion amongst the S. enterica serovars used to interact with the non-polarized and polarized cells. Subsequently, differences were identified between serovars in terms of immune response induced. Serovars Typhimurium and Typhisuis induced a strong innate immune response four and half hours after the beginning of cell stimulation while Choleraesuis, Gallinarum, and Dublin did not. A strong inflammatory response could limit the spread of the porcine serovars to the gut while, with a weak response, bacteria may not be constrained by the immune response enabling severe systemic diseases. Different repertoires of adhesion factors and of secreted protein effectors between Salmonella serovars interacting with IPEC-1 cells probably explains the differences in their early pathogenic behaviours. [ABSTRACT FROM AUTHOR]

This supplement reports the characterization of 18 new Salmonella serovars recognized in 2002 by the WHO Collaborating Centre for Reference and Research on Salmonella: 12 were assigned to S. enterica subspecies enterica, 2 to subspecies salamae, 2 to subspecies diarizonae, 1 to subspecies houtenae and 1 to S. bongori. [Copyright &y& Elsevier]

This supplement reports the characterization of 22 new Salmonella serovars recognized in 2001 by the WHO Collaborating Centre for Reference and Research on Salmonella: 14 were assigned to S. enterica subspecies enterica, 2 to subspecies salamae, 1 to subspecies arizonae, 4 to subspecies diarizonae and 1 to subspecies indica. [Copyright &y& Elsevier]