Evaluation of the health and healthcare system burden due to antimicrobial-resistant Escherichia coli infections in humans: a systematic review and meta-analysis.

BACKGROUND: Assessment of the burden of disease due to antimicrobial-resistant Escherichia coli infections facilitates understanding the scale of the problem and potential impacts, and comparison to other diseases, which allows prioritization of research, surveillance, and funding. Using systematic review and meta-analysis methodology, the objectives were to evaluate whether humans with antimicrobial-resistant E. coli infections experience increases in measures of health or healthcare system burden when compared to susceptible E. coli infections. METHODS: Comprehensive literature searches were performed in four primary and seven grey literature databases. Analytic observational studies of human E. coli infections that assessed the impact of resistance to third/fourth/fifth-generation cephalosporins, resistance to quinolones, and/or multidrug resistance on mortality, treatment failure, length of hospital stay and/or healthcare costs were included. Two researchers independently performed screening, data extraction, and risk of bias assessment. When possible, random effect meta-analyses followed by assessment of the confidence in the cumulative evidence were performed for mortality and length of hospital stay outcomes, and narrative syntheses were performed for treatment failure and healthcare costs. RESULTS: Literature searches identified 14,759 de-duplicated records and 76 articles were included. Based on 30-day and all-cause mortality meta-analyses, regardless of the type of resistance, there was a significant increase in the odds of dying with resistant E. coli infections compared to susceptible infections. A summary mean difference was not presented for total length of hospital stay meta-analyses due to substantial to considerable heterogeneity. Since small numbers of studies contributed to meta-analyses for bacterium-attributable mortality and post-infection length of hospital stay, the summary results should be considered with caution. Studies contributing results for treatment failure and healthcare costs had considerable variability in definitions and reporting. CONCLUSIONS: Overall, resistant E. coli infections were associated with significant 30-day and all-cause mortality burden. More research and/or improved reporting are necessary to facilitate quantitative syntheses of bacterium-attributable mortality, length of hospital stay, and hospital costs. Protocol Registration PROSPERO CRD42018111197.

Prevalence and antimicrobial resistance among Escherichia coli and Salmonella in Ontario smallholder chicken flocks.

Surveillance is an important component of an overall strategy to address antimicrobial resistant bacteria in food animals and the food chain. The poultry market has many points of entry into the Canadian food chain, and some production practices are underrepresented in terms of surveillance. For example, pathogen carriage and antimicrobial resistance surveillance data are limited in smallholder chicken flocks raised for slaughter at provincially inspected abattoirs. In Canada, antimicrobial resistance in Escherichia coli and Salmonella isolated from commercial broiler chicken flocks, slaughtered at federally inspected abattoirs, is monitored by the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS). The objective of this study was to establish baseline information of antimicrobial resistance presence in E. coli and Salmonella isolated from smallholder flocks in Ontario, utilizing CIPARS collection and isolation methodologies, and to compare findings with CIPARS federally inspected abattoir data from Ontario, Canada. Five chickens per flock were sampled from 205 smallholder flocks. Of 1,025 samples, the E. coli prevalence was 99% (1,022/1,025), and 47% (483/1,022) of positive E. coli isolates were resistant to one or more of the 14 antimicrobials. Furthermore, as compared to results reported for the CIPARS commercial flocks, E. coli isolates from smallholder flocks had significantly lower resistance prevalence to six of 14 individual antimicrobials. Recovery of E. coli did not differ between federally inspected and provincially inspected flocks. Salmonella prevalence at the bird level in smallholder flocks was 0.3% (3/1,025), significantly lower (p â‰ª 0.0001, 95% CI 0.080%-0.86%) than federally inspected commercial flocks. The overall differences found between the commercial and smallholder flocks may be explained by differences in poultry husbandry practices and hatchery sources.

Risk factors for acquisition of multidrug-resistant Escherichia coli and development of community-acquired urinary tract infections.

We examined risk factors associated with the intestinal acquisition of antimicrobial-resistant extraintestinal pathogenic Escherichia coli (ExPEC) and development of community-acquired urinary tract infection (UTI) in a case-control study of young women across Canada. A total of 399 women were recruited; 164 women had a UTI caused by E. coli resistant to ⩾1 antimicrobial classes and 98 had a UTI caused by E. coli resistant to ⩾3 antimicrobial classes. After adjustment for age, student health service (region of Canada) and either prior antibiotic use or UTI history, consumption of processed or ground chicken, cooked or raw shellfish, street foods and any organic fruit; as well as, contact with chickens, dogs and pet treats; and travel to Asia, were associated with an increased risk of UTI caused by antimicrobial resistant E. coli. A decreased risk of antimicrobial resistant UTI was associated with consumption of apples, nectarines, peppers, fresh herbs, peanuts and cooked beef. Drug-resistant UTI linked to foodborne and environmental exposures may be a significant public health concern and understanding the risk factors for intestinal acquisition of existing or newly emerging lineages of drug-resistant ExPEC is important for epidemiology, antimicrobial stewardship and prevention efforts.

Prevalence of methicillin-resistant Staphylococcus aureus in Canadian commercial pork processing plants.

AIMS: This study investigated the prevalence of Methicillin-resistant Staphylococcus aureus (MRSA), their spa-types, and antimicrobial resistance profiles at various steps during commercial pork production from three plants designated as A, B and C. METHODS AND RESULTS: Over a period of 1 year 2640 samples from three commercial pork plants were obtained on a rotating basis. Sample sources were: nasal swabs after bleeding (NSAB), nasal swab after scalding (NSASs, plant C) or skinning (NSASk, plants A, B), carcass swabs after pasteurization (CSAP, plant C) or washing (CSAW, plants A, B) and retail pork (RP). Overall MRSA prevalence at each sampling point in the pork plants after adjusting for clustering was: 61·93, 28·38 7·58 and 1·21% for NSAB, NSASc/Sk, CSAP/CSAW and RP respectively. The majority of MRSA isolates from the three pork plants belonged to livestock-associated MRSA spa-types t034 and t011 (3·8%; ST398). The mainly human spa-type t002 (15%) was also recovered. All MRSA isolates were resistant to ß-lactam and tetracycline antibiotics. Overall resistance to tigecycline was found in about 10% of MRSA isolates while <3% isolates were resistant to daptomycin, gentamicin, quinupristin/dalfopristin and trimethoprim/sulfamethoxazole. CONCLUSION: A higher prevalence of MRSA in the nasal cavity of incoming pigs was observed at all three plants, but a notable reduction in MRSA along the pork processing steps occurred. SIGNIFICANCE AND IMPACT OF THE STUDY: The highest prevalence of MRSA was found in the nasal cavity of incoming pigs in three commercial pig slaughter and pork processing plants. A reduction in MRSA prevalence occurred along the processing chain, and pork products from these plants showed significantly lower MRSA than the initial steps of slaughter and processing, suggesting a reduction in MRSA during the slaughter process with minimal cross-contamination.

Epidemiology of Salmonella on the Paws and in the Faeces of Free-Ranging Raccoons (Procyon Lotor) in Southern Ontario, Canada.

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.

Modelling considerations in the analysis of associations between antimicrobial use and resistance in beef feedlot cattle.

A number of sophisticated modelling approaches are available to investigate potential associations between antimicrobial use (AMU) and resistance (AMR) in animal health settings. All have their advantages and disadvantages, making it unclear as to which model is most appropriate. We used advanced regression modelling to investigate AMU-AMR associations in faecal non-type-specific Escherichia coli (NTSEC) isolates recovered from 275 pens of feedlot cattle. Ten modelling strategies were employed to investigate AMU associations with resistance to chloramphenicol, ampicillin, sulfisoxazole, tetracycline and streptomycin. Goodness-of-fit statistics did not show a consistent advantage for any one model type. Three AMU-AMR associations were significant in all models. Recent parenteral tetracycline use increased the odds of finding tetracycline-resistant NTSEC [odds ratios (OR) 1·1-3·2]; recent parenteral sulfonamide use increased the odds of finding sulfisoxazole-resistant NTSEC (OR 1·4-2·5); and recent parenteral macrolide use decreased the odds of recovering ampicillin-resistant NTSEC (OR 0·03-0·2). Other results varied markedly depending on the modelling approach, emphasizing the importance of exploring and reporting multiple modelling methods based on a balanced consideration of important factors such as study design, mathematical appropriateness, research question and target audience.

The distribution of Salmonella enterica serovars and subtypes in surface water from five agricultural regions across Canada.

Serovar prevalence of the zoonotic pathogen, Salmonella enterica, was compared among 1624 surface water samples collected previously from five different Canadian agricultural watersheds over multiple years. Phagetyping, pulsed field gel electrophoresis (PFGE), and antimicrobial resistance subtyping assays were performed on serovars Enteritidis, Typhimurium, and Heidelberg. Serovars and subtypes from surface water were compared with those from animal feces, human sewage, and serovars reported to cause salmonellosis in Canadians. Sixty-five different serovars were identified in surface water; only 32% of these were isolated from multiple watersheds. Eleven of the 13 serovars most commonly reported to cause salmonellosis in Canadians were identified in surface water; isolates of these serovars constituted >40% of the total isolates. Common phagetypes and PFGE subtypes of serovars associated with illness in humans such as S. Enteritidis and S. Typhimurium were also isolated from surface water and animal feces. Antimicrobial resistance was generally low, but was highest among S. Typhimurium. Monitoring of these rivers helps to identify vulnerable areas of a watershed and, despite a relatively low prevalence of S. enterica overall, serovars observed in surface water are an indication of the levels of specific S. enterica serovars present in humans and animals.

Latent class comparison of test accuracy when evaluating antimicrobial susceptibility using disk diffusion and broth microdilution to test Escherichia coli and Mannheimia haemolytica isolates recovered from beef feedlot cattle.

The study objective was to use Bayesian latent class analysis to evaluate the accuracy of susceptibility test results obtained from disk diffusion and broth microdilution using bacteria recovered from beef feedlot cattle. Isolates of Escherichia coli and Mannheimia haemolytica were tested for susceptibility to ampicillin, ceftiofur, streptomycin, sulfisoxazole, tetracycline, and trimethoprim-sulfamethoxazole. Results showed that neither testing method was always or even generally superior to the other. Specificity (ability to correctly classify non-resistant isolates) was extremely high for both testing methods, but sensitivity (ability to correctly classify resistant isolates) was lower, variable in the drugs evaluated, and variable between the two bacterial species. Predictive values estimated using Bayesian Markov chain Monte Carlo models showed that the ability to predict true susceptibility status was equivalent for test results obtained with the two testing methods for some drugs, but for others there were marked differences between results obtained from disk diffusion and broth microdilution tests.

Canadian integrated program for antimicrobial resistance surveillance: Retail food highlights, 2003-2012.

BACKGROUND: The Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS) is a collaborative, integrated program designed to track antimicrobial resistance (AMR) among enteric bacteria isolated from various livestock commodities along the food-producing continuum ("farm to fork") and in humans. OBJECTIVE: To provide a summary of the prevalence and trends in AMR among select bacteria isolated from raw, fresh chicken, pork, and beef in 2012 at the retail food level and to link these data with other findings from CIPARS. METHODS: Meat samples were collected from randomly selected geographic areas across Canada weighted by population for subsequent isolation of bacteria and interpretation of the associated AMR profiles. Salmonella, Campylobacter and generic Escherichia coli (E. coli) were tested in chicken, and E. coli was tested in beef and pork. Data were analyzed for 2012 and temporal and regional trends were examined between 2003 and 2012 by province/region. RESULTS: Overall, resistance levels to Salmonella in retail chicken varied widely by region and year. For example, ceftiofur resistance to Salmonella in retail chicken was significantly lower in 2012 than in 2004 in Ontario and in Québec; however, among all regions sampled, resistance was significantly higher in 2012 compared to 2006. Across all regions sampled, resistance to Campylobacter in retail chicken was relatively low in 2012 (<16%) with the exception of tetracycline resistance. In 2012, ciprofloxacin resistance to Campylobacter in chicken declined in British Columbia but significantly increased in Ontario, compared to 2011. In 2012, ß-lactam resistance to E. coli in retail beef remained low (≤1%) and was also relatively low comparable to previous years in pork. CONCLUSION: In Canada, as is the case worldwide, there is evidence of resistance to medically important antimicrobials among bacteria from retail meats. Resistance among organisms isolated from poultry, beef, and pork at the retail food level is characterized by wide variation over time and across different regions.

Ciprofloxacin-resistant Campylobacter in broiler chicken in Canada.

This case study outlines the patterns of ciprofloxacin resistance in Campylobacter isolated from retail chicken meat in Canada. Campylobacter is the third most common cause of foodborne enteric illness in Canada; it usually causes a self-limited illness, but in some cases antimicrobials may be indicated. Ciprofloxacin (a fluoroquinolone) is an antimicrobial used to treat a number of infections in humans; other fluoroquinolones are used both therapeutically and prophylactically in livestock animals, including broiler chickens. The Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS) has been testing retail chicken meat samples across Canada for the presence of Campylobacter and for resistant strains since 2003. At the end of 2010, CIPARS documented that retail chicken meat samples in Canada contaminated with Campylobacter ranged from 36% in the Maritimes to 42% in British Columbia. Furthermore, levels of ciprofloxacin-resistant Campylobacter varied across the country, with higher percentages in British Columbia (17% in 2010) and Saskatchewan (11%), in comparison with lower percentages in Ontario (5%), Québec (2%, and the Maritimes (4%). In 2011 and 2012, resistance declined in British Columbia and Saskatchewan, but began to rise in Québec and Ontario. Recently, the Canadian poultry industry developed a policy to eliminate the preventive use of third generation cephalosporins and fluoroquinolones in broiler chickens (meat chickens) and broiler breeder chickens (chickens that produce the eggs that will become the broilers). CIPARS will continue to monitor trends in antimicrobial use and resistance following this industry intervention. By following good food preparation and hygiene practices, Canadians can reduce the risks of developing a Campylobacter infection (resistant or susceptible) from retail chicken.

A cross-sectional study examining Campylobacter and other zoonotic enteric pathogens in dogs that frequent dog parks in three cities in south-western Ontario and risk factors for shedding of Campylobacter spp.

An estimated 6 million pet dogs live in Canadian households with the potential to transmit zoonotic pathogens to humans. Dogs have been identified as carriers of Salmonella, Giardia and Campylobacter spp., particularly Campylobacter upsaliensis, but little is known about the prevalence and risk factors for these pathogens in pet dogs that visit dog parks. This study examined the prevalence of these organisms in the faeces of dogs visiting dog parks in three cities in south-western Ontario, as well as risk factors for shedding Campylobacter spp. and C. upsaliensis. From May to August 2009, canine faecal samples were collected at ten dog parks in the cities of Guelph and Kitchener-Waterloo, Ontario, Canada. Owners were asked to complete a questionnaire related to pet characteristics and management factors including age, diet and activities in which the dog participates. Faecal samples were collected from 251 dogs, and 189 questionnaires were completed. Salmonella, Giardia and Campylobacter spp. were present in 1.2%, 6.4% and 43.0% of faecal samples, respectively. Of the Campylobacter spp. detected, 86.1% were C. upsaliensis, 13% were C. jejuni and 0.9% were C. coli. Statistically significant sparing factors associated with the shedding of Campylobacter spp. included the feeding of a commercial dry diet and the dog's exposure to compost. Age of dog had a quadratic effect, with young dogs and senior dogs having an increased probability of shedding Campylobacter spp. compared with adult dogs. The only statistically significant risk factor for shedding C. upsaliensis was outdoor water access including lakes and ditches, while dogs >1 year old were at a lower risk than young dogs. Understanding the pet-related risk factors for Campylobacter spp. and C. upsaliensis shedding in dogs may help in the development of awareness and management strategies to potentially reduce the risk of transmitting this pathogen from dogs to humans.

A cross-sectional study examining the prevalence and risk factors for anti-microbial-resistant generic Escherichia coli in domestic dogs that frequent dog parks in three cities in south-western Ontario, Canada.

Anti-microbial resistance can threaten health by limiting treatment options and increasing the risk of hospitalization and severity of infection. Companion animals can shed anti-microbial-resistant bacteria that may result in the exposure of other dogs and humans to anti-microbial-resistant genes. The prevalence of anti-microbial-resistant generic Escherichia coli in the faeces of dogs that visited dog parks in south-western Ontario was examined and risk factors for shedding anti-microbial-resistant generic E. coli identified. From May to August 2009, canine faecal samples were collected at ten dog parks in three cities in south-western Ontario, Canada. Owners completed a questionnaire related to pet characteristics and management factors including recent treatment with antibiotics. Faecal samples were collected from 251 dogs, and 189 surveys were completed. Generic E. coli was isolated from 237 of the faecal samples, and up to three isolates per sample were tested for anti-microbial susceptibility. Eighty-nine percent of isolates were pan-susceptible; 82.3% of dogs shed isolates that were pan-susceptible. Multiclass resistance was detected in 7.2% of the isolates from 10.1% of the dogs. Based on multilevel multivariable logistic regression, a risk factor for the shedding of generic E. coli resistant to ampicillin was attending dog day care. Risk factors for the shedding of E. coli resistant to at least one anti-microbial included attending dog day care and being a large mixed breed dog, whereas consumption of commercial dry and home cooked diets was protective factor. In a multilevel multivariable model for the shedding of multiclass-resistant E. coli, exposure to compost and being a large mixed breed dog were risk factors, while consumption of a commercial dry diet was a sparing factor. Pet dogs are a potential reservoir of anti-microbial-resistant generic E. coli; some dog characteristics and management factors are associated with the prevalence of anti-microbial-resistant generic E. coli in dogs.

Burden of illness and factors associated with duration of illness in clinical campylobacteriosis.

A population-based study investigated the burden of illness, including the duration of illness associated with laboratory-confirmed cases of campylobacteriosis in two health unit areas. Questionnaire data were collected for 250 cases. The median duration of illness was 8 days and 66% of cases reported symptoms of moderate severity or greater. A Cox proportional hazards model identified antimicrobial use factors associated with a significantly increased rate of symptom resolution (shorter duration of illness): macrolides for less than the recommended number of days, ciprofloxacin for at least 3 days, and antimicrobials not recommended for campylobacteriosis. The impact of antimicrobial use was consistent regardless of when, during the course of illness, the antimicrobial use began. The effectiveness of ciprofloxacin in these results may be due to the low prevalence of resistance to ciprofloxacin in isolates from this study. The effect of antimicrobials not recommended for campylobacteriosis should be further investigated.

Antimicrobial use and resistance in aquaculture: findings of a globally administered survey of aquaculture-allied professionals.

There is limited published information regarding antimicrobial use (AMU) and antimicrobial resistance (AMR) in aquaculture. Our objective was to determine the opinions of aquaculture-allied professionals around the world on the frequency of AMU and AMR in common aquatic species. The study questionnaire included five sections: respondent demographics, extent of AMU in aquaculture, frequency of observations of AMR in aquaculture, AMR monitoring and surveillance and antimicrobial susceptibility testing in various jurisdictions. It was administered in English and Spanish to 604 professionals in 25 countries and with varying expertise in aquaculture. The response rate was 33% (199/604). Over half of the participants had >10 years of experience in aquaculture: 70% (140/199) were involved in fish health/clinical work and their primary experience was with salmon, tilapia, trout, shrimp (including prawn) and/or catfish. Tetracycline use was reported by 28%, 46%, 18%, 37% and 9% of respondents working with catfish, salmon, tilapia, trout and shrimp, respectively. Resistance to tetracycline in one or more species of bacteria was reported as 'frequent-to-almost always' for the same aquaculture species by 39%, 28%, 17%, 52% and 36% of respondents, respectively. 'Frequent-to-almost always' use of quinolone was reported by 70% (32/46) and 67% (8/12) of respondents from the United States and Canada, respectively, where quinolone products are not approved for aquaculture, and extra-label fluoroquinolone use is either prohibited (United States) or discouraged (Canada). Similar frequencies of quinolone use were also reported by the majority of respondents from Europe [70% (7/10)] and Asia [90% (9/10)] where labelled indications exist. This baseline information can be used to prioritize research or surveillance for AMU and AMR in aquaculture.

Longitudinal study of Clostridium difficile and antimicrobial susceptibility of Escherichia coli in healthy horses in a community setting.

Point prevalence studies have reported carriage rates of enteric pathogens in healthy horses, but longitudinal data are lacking. Commensal E. coli is an indicator organism to evaluate antimicrobial resistance of enteric bacteria, yet there are limited data for horses. The objectives of this study were to investigate and molecularly characterize isolates of Clostridium difficile, Clostridium perfringens and Salmonella, collected sequentially over a one year period, and to determine the antibiotic susceptibility profile for E. coli. Fecal samples were collected monthly from 25 adult horses for one year. Selective cultures were performed for all above bacteria. C. difficile isolates were characterized via PCR toxin gene profiling and ribotyping. Broth microdilution was performed to assess antimicrobial susceptibility profiles of E. coli. Toxigenic Clostridium difficile was isolated from 15/275 (5.45%) samples from 10/25 (40%) horses. Four horses were positive at multiple sampling times but different ribotypes were found in three. Ribotypes included 078 (n=6), 001 (n=6) and C (n=3). C. perfringens was not isolated, nor was Salmonella. E. coli was isolated from 232/300 (77%) fecal samples. Resistance to ≥ 1 and ≥ 3 antimicrobials was present in 31/232 (13.4%) and 6/232 (2.6%) respectively. Only two horses shed the same strain of toxigenic C. difficile for more than one month, indicating that shedding is transient. The high number of ribotype 078 is consistent with recent emergence of this strain in the local horse population. The low prevalence of antibiotic resistance in commensal E. coli suggests that healthy horses are not likely a major reservoir of resistance for enteric bacteria.

Antimicrobial resistance in Campylobacter spp. isolated from Ontario sheep flocks and associations between antimicrobial use and antimicrobial resistance.

The objectives of this study were to determine the prevalence of antimicrobial resistance (AMR) in faecal Campylobacter spp. from lambs and adult sheep and associations between antimicrobial use (AMU) and AMR. A total of 275 faecal samples collected during initial and final visits from 51 sheep flocks, including one feedlot, across southern Ontario were tested for the presence of Campylobacter spp. Campylobacter jejuni was detected in 52% (143/275) of the faecal samples, Campylobacter coli in 7% (19/275), Campylobacter lari in 1% (2/275) and 2% (4/275) were non-speciated Campylobacter. Broth microdilution was used to test antimicrobial susceptibility of 162 isolates to nine antimicrobials. Campylobacter jejuni isolates (n = 142) were resistant to tetracycline (39%), ciprofloxacin (4%), nalidixic acid (4%) and telithromycin (1%). C. coli isolates (n = 19) were resistant to tetracycline (74%), and azithromycin, clindamycin, erythromycin, and telithromycin (5%). The C. lari isolate displayed resistance to nalidixic acid. No statistically significant associations were found between AMU and AMR during multivariate modelling in this study.

The prevalence of methicillin-resistant Staphylococcus aureus colonization in feedlot cattle.

Methicillin-resistant Staphylococcus aureus (MRSA) is an important human pathogen and recent evidence has implicated food animals in the epidemiology of human infections in some regions. While the role of food in MRSA transmission and human health relevance are unclear, MRSA can be found in retail meat products internationally, including beef, yet there has been minimal investigation of MRSA in beef cattle. This study involved screening feedlot cattle for nasal and gastrointestinal colonization with MRSA shortly before the time of slaughter. Methicillin-resistant S. aureus was not isolated from any of 491 nasal swabs and 488 faecal samples. This finding is in contrast to studies that have isolated MRSA from retail beef in Canada, performed in the same laboratory using comparable culture techniques. The reason for this discrepancy is unclear but it demonstrates that further study of MRSA in livestock as well as slaughter, processing and retail environments is needed to elucidate the epidemiology of MRSA contamination of meat.

Gene cluster conferring streptomycin, sulfonamide, and tetracycline resistance in Escherichia coli O157:H7 phage types 23, 45, and 67.

Multidrug resistance to streptomycin, sulfonamide, and tetracycline (AMR-SSuT) was identified in 156 of 171 isolates of Escherichia coli O157:H7 of phage types 23, 45, and 67. In 154 AMR-SSuT isolates, resistance was encoded by strA, strB, sul2, and tet(B), which in 59 of 63 tested isolates were found clustered together on the chromosome within the cdiA locus.

Factors related to Campylobacter spp. carriage in client-owned dogs visiting veterinary clinics in a region of Ontario, Canada.

From July 2008 until May 2009, 240 client-owned pet dogs from seven veterinary clinics in the Region of Waterloo, Ontario, Canada participated in a study to determine pet-related management factors that may be associated with the presence of Campylobacter spp. in dogs. The prevalence of Campylobacter spp. carriage in our study population of pet dogs was 22%, with 19% of the dogs positive for C. upsaliensis, and 3% positive for C. jejuni. A significant risk factor from multivariable logistic regression models for both Campylobacter spp. and C. upsaliensis carriage was having homemade cooked food as the dog's diet or added to its diet, and a significant sparing factor for both models was treatment with antibiotics in the previous month. Increasing age of the dog decreased the odds of Campylobacter spp. and C. upsaliensis carriage. Based on the high prevalence of Campylobacter, and specifically C. upsaliensis, further research concerning pet dogs as a risk factor for campylobacteriosis in humans is warranted.

Burden of acute gastrointestinal illness in the Metropolitan region, Chile, 2008.

The purpose of this study was to determine the magnitude and distribution of acute gastrointestinal illness (GI) in the Chilean population, describe its burden and presentation, identify risk factors associated with GI and assess the differences between a 7-day, 15-day and a 30-day recall period in the population-based burden of illness study design. Face-to-face surveys were conducted on 6047 randomly selected residents in the Metropolitan region, Chile (average response rate 75·8%) in 2008. The age-adjusted monthly prevalence of GI was 9·2%. The 7-day recall period provided annual incidence rate estimates about 2·2 times those of the 30-day recall period. Age, occupation, healthcare system, sewer system, antibiotic use and cat ownership were all found to be significant predictors for being a case. This study expands on the discussion of recall bias in retrospective population studies and reports the first population-based burden and distribution of GI estimates in Chile.