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1.
From May through October 2016, we conducted a repeated cross‐sectional study examining the effects of temporal, spatial, flock and demographic factors (i.e. juvenile vs. adult) on the prevalence of Campylobacter and antimicrobial resistant Enterobacteriaceae among 344 fresh faecal samples collected from Canada geese (Branta canadensis) from four locations where birds nested in Guelph, Ontario, Canada. The overall prevalence of Campylobacter among all fresh faecal samples was 9.3% and was greatest in the fall when these birds became more mobile following the nesting season. Based on 40 gene comparative genomic fingerprinting (CGF40), the increase in prevalence noted in the fall was matched by an increase in the number of unique CGF40 subtypes identified. Resistance to colistin was detected most commonly, in 6% of Escherichia coli isolates, and was highest in the late summer months. All colistin‐resistant isolates were negative for the mcr‐1 to mcr‐5 genes; a chromosomal resistance mechanism (PmrB) was identified in all of these isolates. The prevalence of samples with E. coli exhibiting multi‐class resistance or extended spectrum beta‐lactamase was low (i.e. <2% of samples). The intra‐class correlation coefficients, estimated from the variance components of multilevel logistic regression models, indicated that the shedding of Campylobacter and antimicrobial resistant E. coli among geese within a flock (i.e. birds collected from the same site on the same day) was moderately correlated. Spatial, temporal, and spatiotemporal clusters identified using the spatial scan statistic, largely supported the findings from our multi‐level models. Salmonella was not isolated from any of the fresh faecal samples collected suggesting that its prevalence in this population of birds was very low.  相似文献   

2.
Antibiotic resistance mediated by bacterial production of extended‐spectrum beta‐lactamase (ESBL) is a global threat to public health. ESBL resistance is most commonly hospital‐acquired; however, infections acquired outside of hospital settings have raised concerns over the role of livestock and wildlife in the zoonotic spread of ESBL‐producing bacteria. Only limited data are available on the circulation of ESBL‐producing bacteria in animals. Here, we report ESBL‐producing Escherichia coli in wild common vampire bats Desmodus rotundus and livestock near Lima, Peru. Molecular analyses revealed that most of this resistance resulted from the expression of blaCTX‐M‐15 genes carried by plasmids, which are disseminating worldwide in hospital settings and have also been observed in healthy children of Peru. Multilocus sequence typing showed a diverse pool of E. coli strains carrying this resistance that were not always host species‐specific, suggesting sharing of strains between species or infection from a common source. This study shows widespread ESBL resistance in wild and domestic animals, supporting animal communities as a potential source of resistance. Future work is needed to elucidate the role of bats in the dissemination of antibiotic‐resistant strains of public health importance and to understand the origin of the observed resistance.  相似文献   

3.
Salmonella Kentucky is among the most frequently isolated S. enterica serovars from food animals in the United States. Recent research on isolates recovered from these animals suggests there may be geographic and host specificity signatures associated with S. Kentucky strains. However, the sources and genomic features of human clinical S. Kentucky isolated in the United States remain poorly described. To investigate the characteristics of clinical S. Kentucky and the possible sources of these infections, the genomes of all S. Kentucky isolates recovered from human clinical cases in the State of Maryland between 2011 and 2015 (n = 12) were sequenced and compared to a database of 525 previously sequenced S. Kentucky genomes representing 12 sequence types (ST) collected from multiple sources on several continents. Of the 12 human clinical S. Kentucky isolates from Maryland, nine were ST198, two were ST152, and one was ST314. Forty‐one per cent of isolates were recovered from patients reporting recent international travel and 58% of isolates encoded genomic characteristics similar to those originating outside of the United States. Of the five isolates not associated with international travel, three encoded antibiotic resistance genes conferring resistance to tetracycline or aminoglycosides, while two others only encoded the cryptic aac(6′)‐Iaa gene. Five isolates recovered from individuals with international travel histories (ST198) and two for which travel was not recorded (ST198) encoded genes conferring resistance to between 4 and 7 classes of antibiotics. Seven ST198 genomes encoded the Salmonella Genomic Island 1 and substitutions in the gyrA and parC genes known to confer resistance to ciprofloxacin. Case report data on food consumption and travel were, for the most part, consistent with the inferred S. Kentucky phylogeny. Results of this study indicate that the majority of S. Kentucky infections in Maryland are caused by ST198 which may originate outside of North America.  相似文献   

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5.
The objectives of this study were to (i) compare the carriage of Campylobacter and antimicrobial‐resistant Campylobacter among livestock and mammalian wildlife on Ontario farms, and (ii) investigate the potential sharing of Campylobacter subtypes between livestock and wildlife. Using data collected from a cross‐sectional study of 25 farms in 2010, we assessed associations, using mixed logistic regression models, between Campylobacter and antimicrobial‐resistant Campylobacter carriage and the following explanatory variables: animal species (beef, dairy, swine, raccoon, other), farm type (swine, beef, dairy), type of sample (livestock or wildlife) and Campylobacter species (jejuni, coli, other). Models included a random effect to account for clustering by farm where samples were collected. Samples were subtyped using a Campylobacter‐specific 40 gene comparative fingerprinting assay. A total of 92 livestock and 107 wildlife faecal samples were collected, and 72% and 27% tested positive for Campylobacter, respectively. Pooled faecal samples from livestock were significantly more likely to test positive for Campylobacter than wildlife samples. Relative to dairy cattle, pig samples were at significantly increased odds of testing positive for Campylobacter. The odds of isolating Campylobacter jejuni from beef cattle samples were significantly greater compared to dairy cattle and raccoon samples. Fifty unique subtypes of Campylobacter were identified, and only one subtype was found in both wildlife and livestock samples. Livestock Campylobacter isolates were significantly more likely to exhibit antimicrobial resistance (AMR) compared to wildlife Campylobacter isolates. Campylobacter jejuni was more likely to exhibit AMR when compared to C. coli. However, C. jejuni isolates were only resistant to tetracycline, and C.  coli isolates exhibited multidrug resistance patterns. Based on differences in prevalence of Campylobacter spp. and resistant Campylobacter between livestock and wildlife samples, and the lack of similarity in molecular subtypes and AMR patterns, we concluded that the sharing of Campylobacter species between livestock and mammalian wildlife was uncommon.  相似文献   

6.
Increase in the number of small‐scale backyard poultry flocks in the USA has substantially increased human‐to‐live poultry contact, leading to increased public health risks of the transmission of multi‐drug resistant (MDR) zoonotic and food‐borne bacteria. The objective of this study was to detect the occurrence of Salmonella and MDR Gram‐negative bacteria (GNB) in the backyard poultry flock environment. A total of 34 backyard poultry flocks in Washington State (WA) were sampled. From each flock, one composite coop sample and three drag swabs from nest floor, waterer‐feeder, and a random site with visible faecal smearing, respectively, were collected. The samples were processed for isolation of Salmonella and other fermenting and non‐fermenting GNB under ceftiofur selection. Each isolate was identified to species level using MALDI‐TOFF and tested for resistance against 16 antibiotics belonging to eight antibiotic classes. Salmonella serovar 1,4,[5],12:i:‐ was isolated from one (3%) out of 34 flocks. Additionally, a total of 133 ceftiofur resistant (CefR) GNB including Escherichia coli (53), Acinetobacter spp. (45), Pseudomonas spp. (22), Achromobacter spp. (8), Bordetella trematum (1), Hafnia alvei (1), Ochrobactrum intermedium (1), Raoultella ornithinolytica (1), and Stenotrophomonas maltophilia (1) were isolated. Of these, 110 (82%) isolates displayed MDR. Each flock was found positive for the presence of one or more CefR GNB. Several MDR E. coli (n = 15) were identified as extended‐spectrum β‐lactamase (ESBL) positive. Carbapenem resistance was detected in non‐fermenting GNB including Acinetobacter spp. (n = 20), Pseudomonas spp. (n = 11) and Stenotrophomonas maltophila (n = 1). ESBL positive E. coli and carbapenem resistant non‐fermenting GNB are widespread in the backyard poultry flock environment in WA State. These GNB are known to cause opportunistic infections, especially in immunocompromised hosts. Better understanding of the ecology and epidemiology of these GNB in the backyard poultry flock settings is needed to identify potential risks of transmission to people in proximity.  相似文献   

7.
Food animals are considered reservoirs of methicillin‐resistant Staphylococcus aureus (MRSA) and are implicated in their zoonotic transmission in the farm‐to‐plate continuum. LA‐MRSA has been reported as a zoonotic agent that has the potential to spread to humans and may cause infections in at‐risk groups. In this study, whole genome sequencing was used to describe the genetic environment (resistance mechanisms, virulence factors and mobile genetic elements) and investigate the genetic lineages of MRSA isolates from pigs in Cameroonian and South African abattoirs. During March–October 2016, 288 nasal and rectal pooled samples from 432 pigs as well as nasal and hand swabs from 82 humans were collected. Genomic DNA was sequenced using an Illumina MiSeq platform. Generated reads were de novo‐assembled using the Qiagen CLC Genomics Workbench and SPAdes. The assembled contigs were annotated, and antibiotic resistance genes, virulence factors, plasmids, SCCmec and phage elements were identified with ResFinder, Virulence Finder, PlasmidFinder, SCCmec Finder and PHAST, respectively. Core genome single nucleotide analysis was undertaken to assess clonal relatedness among isolates. A lower MRSA prevalence was observed in pigs in Cameroon (n = 1/13; 0.07%) compared with South Africa (n = 4/22; 18.18%), and none of the workers were colonized by MRSA. Genome analysis identified various antibiotic resistance genes along with six virulence factors in all isolates. All MRSA isolates belonged to the clonal lineage ST398 (spa‐type t011) and harboured the type Vc SCCmec and several plasmids. Our study shows that the livestock‐associated MRSA clonal lineage ST398 is already present in both Cameroon and South Africa and is probably underestimated in the absence of molecular epidemiological studies. It reveals the serious food safety and public health threat associated with this animal strain and underscores the need for interventions to contain this resistant clone.  相似文献   

8.
Low‐ and middle‐income countries are experiencing rapid urban population growth, particularly in peri‐urban informal settlements. In these urban areas, animal husbandry remains a valuable source of income and protein‐rich foods but may also present a risk of zoonotic disease threat. To date, there have been studies that have assessed the prevalence and nature of animal ownership in these communities. This cross‐sectional survey assessed the geographical, sociocultural and economic factors behind the presence, ownership and purpose of domestic animals in three informal peri‐urban communities of Kisumu, Kenya. A majority (n = 587) of the study households exhibited domestic animal presence in the living space yet only 32% of households reported animal ownership (n = 252). The purposes of ownership included: for meat/eggs (55%); for income, sale or trade (43%); for milk production (31%); and as companions/pets (31%). Among households that owned animals, 76% reported that at least one animal slept in the house at night. In multivariate logistic regression, the following factors were significantly associated with household animal ownership: ownership of agricultural land (OR = 1.94, 95% CI = 1.12, 3.35), perceiving a strong community bond (OR = 2.28, 95% CI = 1.25, 4.16), and household membership in a community group (OR = 1.64, 95% CI = 1.04, 2.60). This research demonstrates the high prevalence of animal ownership in a low‐income and high‐density peri‐urban neighbourhood of an African city, which may facilitate zoonotic disease transmission. Further research should assess if and to what extent animal ownership in such communities is associated with disease risk.  相似文献   

9.
Wild animals are involved in zoonotic disease transmission cycles. These are generally complex and poorly understood, especially among animals adapted to life in human ecosystems. Raccoons are reservoirs and effective carriers for infectious agents such as Salmonella throughout different environments and contribute to the transference of resistance genes. This study examined the presence of circulating Salmonella sp. in a population of raccoons in a tropical urban environment and evaluated resistance to antibiotics commonly used to treat salmonellosis. A total of 97 raccoons of different ages and sex were included in this study. 49% (38–60 CI) of the faecal samples were positive for Salmonella spp. The study identified 15 circulating serovars with the most prevalent being S. Hartford (7/15), S. Typhimurium (4/15) and S. Bovismorbificans (4/15). These serovars correspond to the serovars detected in humans with clinical symptoms in Costa Rica. 9.5% of the Salmonella strains recovered demonstrated ciprofloxacin resistance, and 7.1% showed resistance to nalidixic acid. This study provides evidence of multiple Salmonella serovars circulating in a population of urban raccoons in Costa Rica. Furthermore, the study confirms the existence of antimicrobial resistance to two antibiotics used to treat human salmonellosis. The findings emphasize the role of the raccoon as a reservoir of Salmonella in the Greater Metropolitan Area of Costa Rica (GAM) and stress the need for active monitoring of the presence and possible spread in antibiotic resistance due to this peri‐domestic carnivore.  相似文献   

10.
Every year, multiple outbreaks of salmonellosis in humans are linked to contact with mail‐order chicks and ducks. The objective of this study was to describe the temporal changes in the prevalence of serovars, genotypes and antimicrobial resistance (AMR) phenotypes of non‐typhoidal Salmonella (NTS) recovered from shipped boxes of mail‐order hatchling poultry in the United States during 2013 to 2015. In each year, a sample of feed stores belonging to a single national chain participated in the study. The store employees submitted swabs or hatchling pads from hatchling boxes and shipment tracking information of the arriving boxes to the investigators. NTS was cultured from the samples and isolates were sent to the National Veterinary Services Laboratories (Ames, IA) for serotyping, pulsed‐field gel electrophoresis (PFGE) and AMR phenotyping. The PFGE patterns of Salmonella serovars isolated from hatchling boxes were compared with those from human outbreaks of salmonellosis linked to live poultry contact. The box‐level prevalence of NTS was significantly higher in 2015 compared to 2014. Also, the population of Salmonella serovars recovered in 2015 was more diverse and substantially different from those recovered in the previous two years. Of PFGE patterns recovered from hatchling boxes, seven distinct patterns in 2015, three in 2014 and four in 2013 were indistinguishable from the PFGE patterns of human outbreaks‐associated strains in the respective years. Importantly, a significant positive correlation was found between the box‐level prevalence of PFGE patterns and the number of human illnesses associated with the same patterns. Also, the proportion of multidrug‐resistant isolates was higher in 2014 and 2015 compared to that in 2013. The results demonstrate that shipments of mail‐order hatchling poultry are frequently contaminated with Salmonella genotypes indistinguishable from human outbreaks‐associated strains each year, and control efforts at hatchery level are likely to have an important public health impact.  相似文献   

11.
Antimicrobial resistance is a worldwide public health threat; hence, current trends tend to reduce antimicrobial use in food‐producing animals and to monitor resistance in primary production. This study aimed at evaluating the impact of antimicrobial use and production system on swine farms in the antimicrobial resistance of Campylobacter, Salmonella and Staphylococcus, the main zoonotic pathogens in pig herds, in order to assess their potential value as sentinel microorganisms in antimicrobial resistance surveillance schemes. A total of 37 Spanish swine farms, 18 intensive and 19 organic/extensive farms, were included in the study. The antimicrobial resistance of 104 Campylobacter, 84 Staphylococcus and 17 Salmonella isolates was evaluated using Sensititre plates following the EUCAST guidelines. Mixed‐effects logistic regression was used to evaluate the influence of production system and antimicrobial use in resistant and multidrug‐resistant (MDR) phenotypes to the antimicrobials tested. The results showed that antimicrobial use was higher (p < .001) on intensive farms than on organic/extensive farms. MDR in Campylobacter and Staphylococcus was lower on organic/extensive farms (OR < .01p < .001). Antimicrobial resistance in Campylobacter and Staphylococcus isolates was, also for most of the antimicrobials studied, significantly higher in intensive than organic/extensive pig herds. Tetracycline resistance was associated with total antimicrobial consumption in both microbial species (p < .05), and some cross‐associations between distinct antimicrobial substances were established, for instance resistance to erythromycin was associated with macrolide and phenicol consumption. No significant associations could be established for Salmonella isolates. The results demonstrate the link between antimicrobial consumption and resistance in zoonotic bacteria and evidence the potential value of using Campylobacter and Staphylococcus species in monitoring activities aimed at determining the impact of antimicrobials use/reduction on the occurrence and spread of antimicrobial resistance.  相似文献   

12.
Summary Spirulina (Athrospira sp.) is an edible microalga and a highly nutritious potential feed resource for many agriculturally important animal species. Research findings have associated Spirulina to improvements in animal growth, fertility, aesthetic and nutritional product quality. Spirulina intake has also been linked to an improvement in animal health and welfare. Its influence over animal development stems from its nutritive and protein‐rich composition, thus leading to an increased commercial production to meet consumer demand. Consequently, Spirulina is emerging as a cost‐effective means of improving animal productivity for a sustainable and viable food security future. However, our present knowledge of animal response to dietary Spirulina supplementation is relatively scanty and largely unknown. Therefore, the primary objective of this paper was to review past and current findings on the utilisation of Spirulina as a feed supplement and its impact on animal productivity and health. Only animals deemed to be of agricultural significance were investigated; hence, only ruminants, poultry, swine and rabbits and their responses to dietary Spirulina supplementation are covered.  相似文献   

13.
In order to estimate the prevalence of AmpC‐ and ESBL β‐lactamase‐producing Enterobacteriaceae in the faecal flora of a healthy domestic canine population, faecal samples were obtained from healthy dogs receiving routine parasitology screening at the Ohio State University Veterinary Medical Center, between January 2013 and April 2013. Samples were screened for the presence of AmpC and ESBL β‐lactamase phenotypes, and the clinically important genotypes, blaCMY and blaCTX‐M, were confirmed via conventional PCR. Minimum inhibitory concentrations were determined for isolates and plasmids were characterized. Two hundred and twelve canine faecal samples were screened, of which 30 harboured isolates carrying the AmpC blaCMY, representing 14.2% of the population (95% CI: 9.4–18.9%). Nine samples harboured isolates that carried the ESBL blaCTX‐M, representing 4.2% of the population (95% CI: 1.5–7.0%). Isolates containing blaCMY harboured multiple plasmid replicon types, while isolates containing blaCTX‐M harboured few plasmid replicon types. Our results suggest that domestic dogs may serve as a reservoir for extended‐spectrum cephalosporin resistance genes for other domestic animal populations as well as for their human companions. This represents a potential veterinary and public health risk that warrants further investigation and continued surveillance to ascertain the nature and extent of the risk. The high level of diversity of plasmid content among isolates harbouring blaCMY suggests broader dissemination relative to blaCTX‐M isolates.  相似文献   

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15.
Raccoons are common in urban and rural environments and can carry a wide range of bacteria, including Salmonella, that can negatively affect human and livestock health. Although previous studies have reported that raccoons shed a variety of Salmonella serovars in their faeces, it is unknown whether Salmonella is carried on raccoon paws. Our objective was to compare the prevalence of Salmonella on the paws and in the faeces of raccoons in south‐western Ontario. Raccoons were sampled in a repeat cross‐sectional study on five swine farms and five conservation areas from May to October 2012. A total of 416 paired faecal and paw samples were collected from 285 individual raccoons. Salmonella was detected in 18% (75/416; 95% CI, 14–22%) and 27% (111/416; 95% CI, 22–31%) of paw and faecal samples, respectively. Salmonella was detected only on paws in 8% (35/416; 95% CI, 5.9–11.5%), only in faeces in 17% (71/416; 95% CI, 13.6–21.0%) and on both paws and in faeces in 10% (40/416; 95% CI, 7.0–12.9%) of raccoon captures. Multilevel logistic regression models were used to examine associations between the presence of Salmonella and age (adult, juvenile), sex (male, female), location type (swine farm, conservation area), sample type (faeces, paw) and season (May–July and August–October). Random intercepts were included to account for clustering by individual animal and location. Significant differences, that varied by sample type and season, were noted in the prevalence of Salmonella carriage between sexes. Raccoons can carry Salmonella serovars known to infect humans and livestock on their paws and/or in their faeces and therefore have the potential to mechanically and biologically disseminate Salmonella among livestock facilities and human recreational areas.  相似文献   

16.
In the 3 years since the first report of canine alveolar echinococcosis (AE) in Ontario, three additional cases have been diagnosed in the province. Of the four cases reported to date, three have had no known history of travel outside the province. It is possible that this development is an indication of previously unrecognized environmental contamination with Echinococcus multilocularis eggs in some areas of the province. If so, there is the potential for an emerging threat to human health. This article describes a local public health department's investigation of the possible exposure to E. multilocularis of a number of individuals who had had contact with the latest of the four cases of canine AE, and summarizes a comprehensive decision process that can be used by public health departments to assist in the follow‐up of such exposures.  相似文献   

17.
The increasing prevalence of antibiotic resistance among bacteria is one of the most intractable challenges in 21st‐century public health. Dipterans that associate with livestock, livestock waste products and cadavers have the potential to acquire livestock‐associated antibiotic‐resistant bacteria (LA‐ARB) and transmit them to humans. In this study, piglet cadavers were used to attract saprophage dipterans from the environment and those dipterans were sampled for the presence of LA‐ARB. In the first trial, culturable microbes resistant to both aminoglycoside and β‐lactam antibiotics were found in all cadavers and masses of dipteran larvae, and in three‐quarters of adult dipterans. In the second trial, over 130 culturable bacterial colonies resistant to β‐lactams were isolated from the cadavers, larval and adult dipterans. Over 100 of those colonies were coliform or metabolically similar bacteria. Adult dipterans carried β‐lactam resistant staphylococci, whereas those bacterial types were absent from larval dipterans and cadavers, suggesting they were picked up from elsewhere in the environment. This research indicates that LA‐ARB are ubiquitous in pig farms, and dipterans have the potential to carry medically important microbes. Further research is encouraged to determine the extent to which dipterans acquire microbes from animal agriculture relative to other environments.  相似文献   

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The aim of this research was to study the phenotypic resistances to disinfectants and antibiotics in strains of methicillin‐resistant Staphylococcus aureus (MRSA) obtained from Canary black pigs. Analyses were performed on 54 strains of MRSA, isolated in Canary black pigs from the province of Tenerife (Spain); all of them carried the mecA gene. The strains were isolated by means of nasal swab samples of healthy pigs, collected under veterinarian supervision. Bactericidal activity of antiseptics and disinfectants was tested by means of the dilution–neutralization method. Susceptibility to the disinfectants glutaraldehyde, peracetic acid and silver nitrate was assessed, as well as to the antiseptics chlorhexidine, benzalkonium chloride and povidone iodine. Susceptibility to a wide array of antibiotics representing the main groups was determined by means of the disc diffusion method. All the strains demonstrated susceptibility to the disinfectants tested at the recommended concentration, and even to dilutions equal to or lesser than 1/16. The most effective antiseptic and disinfectant were, respectively, chlorhexidine and silver nitrate. With regard to the antibiotics, the strains proved to be multiresistant. All presented phenotypic resistance to the β‐lactam antibiotics ampicillin, penicillin and cefoxitin, as well as to numerous aminoglycosides, tetracycline and trimethoprim–sulfamethoxazole. It was also observed that 61.1% of the strains were carriers of plasmids. Our results underline that in the strains such as MRSA, which show multiple resistances to antibiotics, the antiseptics and disinfectants show great efficacy. Moreover, as other authors also suggest, for the treatment and prevention of infections caused by MRSA, the use of β‐lactam and aminoglycoside antibiotics may be less effective.  相似文献   

20.
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