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Human campylobacteriosis, a notifiable disease in Canada, is the most common cause of bacterial enteric infections among persons in Canada; in 2005, the incidence rate of campylobacteriosis was 30.9 cases per 100,000 population(1). In chickens, Campylobacter spp. are not clinically relevant; however, the presence of these bacteria in poultry represents a potential threat to public health (2). Ciprofloxacin, a fluoroquinolone antimicrobial drug, is indicated for the treatment of respiratory, urinary, skin, and bone/joint infections and gastroenteritis in adults (3). In 2008 in Canada, fluoroquinolones were the fourth most frequently dispensed class of antimicrobial drug (dispensed for oral use by retail pharmacists; www.phac-aspc.gc.ca/cipars-picra/2008/4-eng.php#Hum0). A study investigating antimicrobial drug use and resistance in 2 health units in Ontario found that ciprofloxacin was the antimicrobial drug most frequently used to treat human campylobacteriosis (4). Fluoroquinolones are considered “critically” or “very” important to human medicine by the World Health Organization (5) and the Veterinary Drugs Directorate (VDD), Health Canada (6). The veterinary fluoroquinolones enrofloxacin and danofloxacin are VDD Category I antimicrobial drugs labeled for use in companion animals and beef cattle, but they are not labeled for use in poultry. The VDD has established a policy recommending against the extra-label use of Category I antimicrobial drugs in food-producing animals (7); however, Canada does not have legislation restricting this extra-label use.

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.

Urinary tract infections can be difficult and expensive to treat. Most (85%) are caused by bacteria called E. coli. Historically, doctors have believed that these urinary tract E. coli came from the patient’s own intestines. But recently, Canadian researchers discovered that not only can these E. coli come from outside the patient’s intestines, they can actually come from outside the patient: from food. After comparing the genetic makeup of E. coli from human urinary tract infections with E. coli from retail meat (chicken, beef, and pork), they concluded that chickens are a likely source of E. coli and that the infections probably come directly from the chickens themselves, not from human contamination during food processing. Therefore, prevention of E. coli urinary tract infections in people might need to start on chicken farms., We previously described how retail meat, particularly chicken, might be a reservoir for extraintestinal pathogenic Escherichia coli (ExPEC) causing urinary tract infections (UTIs) in humans. To rule out retail beef and pork as potential reservoirs, we tested 320 additional E. coli isolates from these meats. Isolates from beef and pork were significantly less likely than those from chicken to be genetically related to isolates from humans with UTIs. We then tested whether the reservoir for ExPEC in humans could be food animals themselves by comparing geographically and temporally matched E. coli isolates from 475 humans with UTIs and from cecal contents of 349 slaughtered animals. We found genetic similarities between E. coli from animals in abattoirs, principally chickens, and ExPEC causing UTIs in humans. ExPEC transmission from food animals could be responsible for human infections, and chickens are the most probable reservoir.

Use of this drug in chickens may limit effectiveness of cephalosporins in treating human infections., The Canadian Integrated Program for Antimicrobial Resistance Surveillance describes a strong correlation (r = 0.9, p

An observational study was conducted of chicken and turkey flocks slaughtered at federal processing plants in the province of Quebec, Canada. The objectives were to estimate prevalence of drug use at hatchery and on farm and to identify antimicrobial resistance (AMR) in cecal Escherichia coli and Enterococcus spp. isolates and factors associated with AMR. Eighty-two chicken flocks and 59 turkey flocks were sampled. At the hatchery, the most used antimicrobial was ceftiofur in chickens (76% of flocks) and spectinomycin in turkeys (42% of flocks). Virginiamycin was the antimicrobial most frequently added to the feed in both chicken and turkey flocks. At least 1 E. coli isolate resistant to third-generation cephalosporins was present in all chicken flocks and in a third of turkey flocks. Resistance to tetracycline, streptomycin, and sulfisoxazole was detected in90% of flocks for E. coli isolates. Antimicrobial resistance (AMR) was observed to bacitracin, erythromycin, lincomycin, quinupristin-dalfopristin, and tetracycline in both chicken and turkey flocks for Enterococcus spp. isolates. No resistance to vancomycin was observed. The use of ceftiofur at hatchery was significantly associated with the proportion of ceftiofur-resistant E. coli isolates in chicken flocks. In turkey flocks, ceftiofur resistance was more frequent when turkeys were placed on litter previously used by chickens. Associations between drug use and resistance were observed with tetracycline (turkey) in E. coli isolates and with bacitracin (chicken and turkey), gentamicin (turkey), and tylosin (chicken) in Enterococcus spp. isolates. Further studies are needed to provide producers and veterinarians with alternative management practices and tools in order to reduce the use of antimicrobial feed additives in poultry.Une étude observationnelle portant sur des élevages de poulets et de dindons abattus dans des usines de transformation sous inspection fédérale situées dans la province de Québec (Canada) a été réalisée. Les objectifs étaient d’estimer la prévalence d’utilisation de médicaments au couvoir et en ferme, la prévalence de résistance aux antimicrobiens dans des isolats caecaux d’

Antimicrobial resistance (AMR) surveillance systems are generally not specifically designed to detect emerging resistances and usually focus primarily on resistance to individual drugs. Evaluating the diversity of resistance, using ecological metrics, allows the assessment of sampling protocols with regard to the detection of rare phenotypes, comprising combinations of resistances. Surveillance data of phenotypic AMR of Canadian poultry Salmonella Heidelberg and swine Salmonella Typhimurium var. 5- were used to contrast active (representative isolates derived from healthy animals) and passive (diagnostic isolates) surveillance and assess their suitability for detecting emerging resistance patterns. Although in both datasets the prevalences of resistance to individual antimicrobials were not significantly different between the two surveillance systems, analysis of the diversity of entire resistance phenotypes demonstrated that passive surveillance of diagnostic isolates detected more unique phenotypes. Whilst the most appropriate surveillance method will depend on the relevant objectives, under the conditions of this study, passive surveillance of diagnostic isolates was more effective for the detection of rare and therefore potentially emerging resistance phenotypes.

Increased reliance on seafood has brought to light concerns regarding food safety, but the information to inform risk assessment or surveillance needs is lacking. A scoping study (ScS) was conducted to characterize published research investigating selected zoonotic bacteria and public health topics in various wild and farmed aquatic species and seafood. This was followed by a systematic review (SR) on selected bacteria (Aeromonas spp., generic Escherichia coli, Salmonella spp., and Vibrio spp.) and aquatic species (clams, mussels, oysters, salmon, and shrimp [including prawn]); a meta-analysis (MA) was conducted only at the retail level due to considerable variability among various pathogen/seafood combinations. The ScS revealed the most frequently investigated themes were farm-level prevalence and intervention research for Vibrio spp. and Aeromonas spp. Antimicrobial use (AMU) and the association between AMU and antimicrobial resistance were rarely investigated. The SR indicated a consistent lack of reporting regarding study methodology and results, precluding the use of many studies in and full benefits of MA. MA of Aeromonas, E. coli, and Salmonella prevalence in retail salmon resulted in pooled estimates of 13% (6-27%), 2% (0.1-11%), and 1% (0-5%), respectively. When MA of pathogen/seafood combination resulted in statistically significant heterogeneity (p0.1), median/range were reported at the region level. The results from our ScS, SR, and MA could be used for better design of future bacteriological surveys of seafood and as inputs for risk assessments or surveillance initiatives in this field.

SUMMARYUsing systematic review methodology, global research reporting the frequency of zoonotic bacterial pathogens, antimicrobial use (AMU) and antimicrobial resistance (AMR) in ornamental fish, and human illness due to exposure to ornamental fish, was examined. A survey was performed to elicit opinions of aquaculture-allied personnel on the frequency of AMU and AMR in ornamental fish. The most commonly reported sporadic human infections were associated withMycobacterium marinum, whileSalmonellaParatyphi B var. Java was implicated in all reported outbreaks.Aeromonasspp. were most frequently investigated (n=10 studies) in 25 studies surveying ornamental fish from various sources. High levels of resistance were reported to amoxicillin, penicillin, tetracycline and oxytetracycline, which was also in agreement with the survey respondents' views. Studies on AMU were not found in our review. Survey respondents reported frequent use of quinolones, followed by tetracyclines, nitrofurans, and aminoglycosides. Recommendations for future surveillance and public education efforts are presented.

OBJECTIVE:To describe rates of antimicrobial resistance (AMR) amongSalmonellaandShigellaisolates reported in five Canadian provinces, focusing on clinically important antimicrobials.METHODS:The authors retrospectively investigated AMR rates among 6219Salmonellaand 1673Shigellaisolates submitted to provincial public health laboratories in Alberta, Newfoundland and Labrador, Ontario, Prince Edward Island and Saskatchewan from 1997 to 2000; these isolates were estimated to represent 41% ofSalmonellacases and 72% ofShigellacases reported by the study provinces.RESULTS:AmongSalmonellaisolates, 27% (1704 of 6215) were resistant to ampicillin, 2.2% (135 of 6122) to trimethoprim/sulfamethoxazole, 1.5% (14 of 938) to nalidixic acid, 1.2% (one of 84) to lomafloxacin and 0.08% (five of 6163) to ciprofloxacin. AmongShigellaisolates, 70% (1144 of 1643) were resistant to trimethoprim/sulfamethoxazole, 65% (1079 of 1672) to ampicillin, 3.1% (eight of 262) to nalidixic acid, 0.49% (eight of 1636) to ciprofloxacin, 0.14% (one of 700) to ceftriaxone and 0.08% (one of 1292) to ceftazidime.CONCLUSIONS:Higher rates of resistance to clinically important antimicrobials (including ciprofloxacin) were observed among bothSalmonellaandShigellaisolates than has previously been reported. Current Canadian data on rates of AMR for these pathogens are required.

Risk factors associated with failure of passive transfer of immunity (FPT) were evaluated among newborn beef calves in Québec. Physical examination was performed on calves born of a normal calving and blood samples were collected for determination of health status and measurement of serum concentration of immunoglobulin (Ig) G1. Of 225 calves, from 45 herds, 19 % showed FPT (serum IgG1 concentration < 10.0 g/L). Calves born in a stanchion-stall were more likely to show FPT (OR: 10.2). Calves bottle-fed colostrum were less at risk for FPT (OR: 0.06). Calf gender, month of birth, dam parity, and dam body condition score were not associated with FPT. No association was detected between FPT and health status. Special care should be given to calves born from cows in a stanchion-stall to ensure adequate colostrum intake. Failure of passive transfer of immunity should be considered with other risk factors when investigating morbidity.

In 173 urban residents and 232 rural dairy-farm residents (age range, 0-70 years) who were stratified for age, the frequency of antiverocytotoxin 2 antibodies (VT2 Abs) (frequency in urban residents, 46%; frequency in rural residents, 65%) was significantly higher than that of antiverocytotoxin 1 antibodies (VT1 Abs) (frequency in urban residents, 12%; frequency in rural residents, 39%) (P< or =.001). The frequency of VT2 Abs (93%) was also significantly higher than that of VT1 Abs (50%) in 14 patients with hemolytic uremic syndrome (HUS) associated with verocytotoxin-producing Escherichia coli (VTEC) strains that expressed both toxins. In urban residents, the frequency of both antibodies tended to decrease between the first and the second decades of life, and it then increased until the fifth decade of life, before, in the case of VT2 Abs, decreasing again. This pattern, which inversely reflects the age-related incidence of HUS, is consistent with a role for antiverocytotoxin antibodies in protective immunity. In dairy-farm residents, peak frequencies of antibodies to both toxins occurred during the first decade of life and remained elevated for 3 decades before decreasing, a pattern consistent with frequent exposure to bovine VTEC from an early age.