Zoonoses and Public Health最新文献

Introduction: Lyme disease (LD) is caused by infection with the bacteria Borrelia burgdorferi sensu lato (Bb) through the bite of an infected Ixodes spp. tick. LD has emerged as a public and animal health issue in Canada, with human incidence increasing in part due to the expansion of Ixodes scapularis ticks and their vertebrate hosts. We sought to provide the first comprehensive summary of published tick and animal surveillance literature regarding LD in Canada to describe changes in LD over time.

Methods: We conducted a review to identify peer-reviewed LD-focused tick, mammal, and bird surveillance articles in three online databases between 1975 and 2023. Data on study characteristics, data collection years, and surveillance methods and findings were extracted. Descriptive statistics were reported.

Results: In total, 115 studies were included for review. Results showed an increase in published surveillance literature and changes in study approaches and their provincial distribution over time, coinciding with increased LD cases in Canada. Seventy-four studies were published after 2014 when Canada's Federal Framework on Lyme Disease Act was introduced, and two-thirds of these studies focused on tick surveillance only. Overall, 58% of studies involved surveillance in Ontario but increases in all other provinces were observed after 2009.

Conclusions: Observed changes in five decades of LD-related tick and animal surveillance literature helps document the historical rapid spread of Ixodes and Bb across provinces. This can provide lessons for other regions that may transition from emerging to endemic status for LD in the coming years.

Introduction: In Brazil, the emergence of feline sporotrichosis, a neglected subcutaneous mycosis primarily transmitted by cats and caused by the fungus Sporothrix brasiliensis, has been monitored via molecular tools. This approach underscores the geographic expansion of this disease and highlights the critical role of molecular surveillance in understanding its epidemiology and guiding public health interventions.

Methods: We investigated three domestic cats (Felis catus) with multiple skin lesions in Picos, Piauí, Brazil. The cats were examined, and samples were collected for laboratory diagnosis, including cytological evaluation, fungal culture, and molecular characterisation. The molecular analysis involved a one-tube multiplex probe-based qPCR assay for the diagnosis of Sporothrix species, mating-type determination, and amplified fragment length polymorphism (AFLP, EcoRI-GA/MseI-AG) to assess genetic similarity and potential origin.

Results: All three cats were diagnosed with sporotrichosis caused by the hypervirulent S. brasiliensis. A probable case of zoonotic transmission has been reported in a 12-year-old girl who developed Parinaud oculoglandular syndrome after contact with one of the cats with sporotrichosis. The molecular analysis revealed that the cat isolates were MAT 1-2 and formed a single cluster according to the AFLP analysis, suggesting direct transmission (cat-cat) and a potential founder effect. The isolates were also closely related to strains from Pernambuco and Southeast Brazil, indicating a possible introduction from these regions.

Conclusions: Identifying S. brasiliensis in Piauí emphasises the need for increased awareness and control measures to prevent further spread. The predominance of the MAT1-2 idiomorphs and the genetic similarity among outbreak isolates suggest clonal expansion, which could have significant implications for public health and veterinary practices. Considering its zoonotic potential and environmental adaptability, a One Health approach is crucial for managing and controlling the spread of cat-transmitted sporotrichosis.

Background: Companion animals, like household dogs, are an overlooked transmission point for zoonotic pathogens such as nontyphoidal Salmonella (NTS). Given the proximity of dogs to humans and the use of critically important antibiotics in companion animal medicine, household dogs represent a risk for the spread of antimicrobial-resistant (AMR) Salmonella.

Methods and results: To this end, we aimed to leverage existing biosurveillance infrastructure to investigate AMR and the zoonotic potential of NTS isolated from dogs and humans. We identified all NTS strains isolated from domestic dogs via the Veterinary Laboratory Investigation and Response Network between May 2017 and March 2023 (N = 87), and spatiotemporally matched strains isolated from humans in the NCBI Pathogen Isolate Browser (N = 77). These 164 strains, collected from 17 states in the United States, formed the basis of our analysis. Strains isolated from dogs comprised diverse serovars, with most being clinically relevant to human health. All strains possessed AMR determinants for drug classes deemed critically or highly important by the World Health Organization. We identified sixteen NTS isolates from humans closely related to ≥1 of six dog-associated strains.

Conclusions: Collectively, our data emphasize the importance of antimicrobial stewardship and sustained biosurveillance beyond human- and agriculture-associated veterinary medicine, using a One-Health framework that accounts for all transmission points including companion animals.

Brucellosis is one of the most important zoonoses worldwide, primarily affecting livestock but also posing a serious threat to public health. The major Brucella species are known to cause a feverish disease in humans with various clinical signs. These classical Brucella species are (re-)emerging, but also novel strains and species, some of them transmitted from rodents, can be associated with human infections. As a result of our review on rodent-borne brucellosis, we emphasise the need for more comprehensive surveillance of Brucella and especially Brucella microti in rodent populations and call for further research targeting the ecological persistence of rodent-associated Brucella species in the environment, their epizootic role in wild rodents and their virulence and pathogenicity for wildlife.

Introduction: Judicious antimicrobial use is essential for the continued treatment of infections in small and mixed animal veterinary medicine. To better support Washington (WA) State veterinarians in antimicrobial stewardship, we surveyed licensed small and mixed animal veterinarians and led group conversations regarding antimicrobial prescription practices.

Methods: Survey questions included demographic information, factors influencing prescription practices and clinical cases. Responses were summarised and logistic regressions were performed to identify factors associated with antibiotic treatment choices. Group conversations, led by a licensed veterinarian, focused on resource gaps for veterinarians, management of clinical scenarios and interpretation of minimum inhibitory concentrations (MICs) and breakpoints. A systematic qualitative analysis of conversation transcripts identified key themes such as common barriers to stewardship.

Results: Among 53 responses to clinical scenarios, veterinarians selected the most appropriate treatment choice, according to a veterinary microbiologist, 62% of the time. Variability was observed in culture and susceptibility practices and antibiotic choices. Survey respondents reported an influence of the client ability to medicate (92%), considerations of resistance (91%), client finances (75%) and availability of antimicrobials (75%) on their prescription decisions. There were no significant associations between opinions about contributing factors to antimicrobial resistance (AMR) or guidelines used and treatment choices in clinical scenarios. Among 15 veterinarians interviewed in group conversations, a systematic qualitative analysis of conversation transcripts revealed key themes, including reliance on human medicine as a resource and a lack of support for veterinarians in interpreting MICs and breakpoints.

Conclusions: The variability in veterinary antibiotic treatment decisions in this study suggests a need for further dissemination of standardised antimicrobial stewardship resources for veterinarians. Client-related challenges and the cost of culture and susceptibility are major barriers to stewardship. To address these barriers, it is necessary to provide standardised, easy-to-access guidance for veterinarians in interpreting MICs and breakpoints, as well as develop antimicrobial use resources for clients.

Mycobacterium bovis and Mycobacterium tuberculosis are the most relevant among pathogenic mycobacteria, both belonging to the M. tuberculosis complex (MTC). Samples of blood, liver, spleen, kidneys, lungs and caseous tubercles were collected from a free-ranging juvenile black capuchin monkey (Sapajus nigritus) showing non-specific signs of illness. Macroscopic findings included emaciation, a caseous lesion in a tooth and gingiva, disseminated nodules in both lungs and left kidney parenchyma and caseous nodules on the pleura and mesentery. The lesions suggested MTC infection, a diagnosis subsequently supported in the lung by bacilloscopy, immunochromatography and PCR. A multiplex PCR further validated the presence of M. bovis genes. Cases of tuberculosis in platyrrhine primates have only been reported in animals maintained in captivity. We describe for the first time the pathological and molecular findings of M. bovis infection in a free-ranging platyrrhine monkey within an area of intense human-wildlife interaction, which has important implications from a One Health perspective.

Introduction: Antimicrobial resistance (AMR) is one of the leading public health threats globally. AMR genes can be transferred between bacteria through lateral gene transfer, and AMR organisms can spread through environments by contaminated water, agriculture and animals. Thus, widespread environmental dissemination of bacteria and lateral gene transfer facilitate AMR transmission pathways. Farm environments in dairy and calf production are known to harbour AMR bacteria that pose a risk for food contamination and to workers in direct or indirect contact with animals. Escherichia coli is present in farm environments and is known to participate in lateral gene transfer, providing a good marker of resistance genes in each environment.

Methods: In this study, E. coli from nine cohorts of calves was isolated at different time points from nine barns, nine trailers and one slaughterhouse environment in a single special-fed veal calf production facility. The antimicrobial susceptibility to 15 antimicrobials, classified as highly or critically important by the World Health Organization, was characterised for E. coli isolates using Kirby-Bauer disk diffusion.

Results: The highest proportion of isolates showing multidrug resistance was present in barn environments (51.7%), where calves were housed from their arrival at < 2 weeks of age until they were transported to slaughter. Additionally, 15 E. coli isolates were resistant to 11 of the 15 antimicrobials tested. Trailer and slaughterhouse environments had greater prevalence of resistance after accommodating calves, including resistance to third-generation cephalosporins.

Conclusion: These data highlight the importance of calf environments in the dissemination of resistant bacteria and gives insight into where interventions could be most effective in combatting antimicrobial-resistant bacteria that could infect humans and livestock.

Introduction: Sporotrichosis is a chronic infectious mycosis caused by traumatic implantation of Sporothrix spp., which poses a significant challenge to public health because of its zoonotic nature. It affects humans and other animals, particularly cats. This study investigated epidemiological trends and spatial distribution of feline sporotrichosis in Espírito Santo between 2017 and 2022.

Methods: This study collected diagnostic data on sporotrichosis from the Veterinary Pathology Laboratory and Center for Infectious Diseases in Espírito Santo from 2017 to 2022. Statistical analyses were performed using STATA and spatial analyses were performed using ArcGIS software to create maps and identify hotspots. Kernel density estimation and directional mean statistics were applied to visualise the disease concentration and transmission trends.

Results: The results showed a significant increase in feline sporotrichosis cases in Espírito Santo from 2017 to 2022, with hotspots identified in urban and densely populated areas. Anchieta, Aracruz and Vila Velha reported the highest numbers of cases. Spatial analysis indicated a spread towards the central and northern coastal regions.

Conclusion: This study highlights the growing threat of feline sporotrichosis in Espírito Santo, Brazil, particularly in densely populated urban areas. This underscores the urgent need for comprehensive public health strategies that address urbanisation, human-animal interactions and managing stray cat populations. Effective control measures and enhanced surveillance are crucial to mitigate the spread of this zoonotic disease. Importantly, this study provides valuable insights into the epidemiology of sporotrichosis in Brazil and offers a framework for other regions identified as emerging hotspots that face similar challenges.

Introduction: Consumer demand for pasture raised, antibiotic-free poultry products has led to an increase in pastured poultry operations within the United States. Given the level of environmental interaction and the potential increase in exposure to foodborne pathogens in these settings, a greater understanding of the prevalence and diversity of Campylobacter populations inherent within pastured poultry flocks is needed.

Methods: To achieve this, 40 pastured poultry flocks from nine farms were sampled using a farm-to-fork strategy, and Campylobacter was isolated and characterised from preharvest (faeces, soil) through postharvest (caeca, whole carcass rinse) to the final product the consumer would purchase (whole carcass rinse).

Results: Campylobacter was isolated from 872 of 1820 samples, showing an overall prevalence of 47.91%. The caeca showed the highest (p < 0.05) Campylobacter load (4.64 log₁₀ CFU/mL) and prevalence (95.5%), while the final product whole carcass rinses had the lowest (p < 0.05) Campylobacter load (0.32 log₁₀ CFU/mL) and prevalence (15.45%), suggesting that the Campylobacter load in the caeca may not be indicative of the Campylobacter load on the final product. Of the 872 positive samples, 337 Campylobacter isolates were selected for further characterisation. Campylobacter jejuni and Campylobacter coli comprised 74.18% (250/337) and 21.95% (74/337) of the selected isolates respectively. While the Campylobacter isolates displayed resistance to several antibiotics, the most common resistance for both C. jejuni and C. coli was against tetracycline (55.86% and 70.31% respectively). Multidrug resistance phenotypes (≥ 3 antibiotic classes) were relatively low for both C. jejuni (2.80%) and C. coli (9.45%).

Conclusions: Campylobacter load, prevalence and diversity were more affected by farm location than by the type of sample from which the Campylobacter was isolated. Overall, these results indicated a need for farm-specific Campylobacter mitigation strategies to ensure the safety of these increasingly in-demand poultry products.