Festival de Innovación Educativa de la UPC. Ponente: Dra. Verónica Ormea / El primer FIE de la UPC es un espacio de docentes para docentes, en donde se compartirán las estrategias innovadoras de aprendizaje que se han venido aplicando en los últimos meses de educación online. Es una oportunidad para intercambiar conocimiento, seguir aprendiendo y atrevernos a innovar como parte del proceso de enseñanza y aprendizaje.

In Canada, parasitism in people and well-managed animal populations is less common now than a century ago, likely due to accessible anthelmintics, heightened public awareness, and improved sanitation. Some zoonotic parasites, such as Echinococcus canadensis are now rarely diagnosed in people, but persist mainly in northern populations where diagnostic services are limited. Veterinary services are also limited in these areas, and as a result, human and animal incidence data does not exist, is outdated, or underestimates the true incidence. We closed this knowledge gap in certain areas of western Canada by determining the prevalence of E. canadensis and other zoonotic parasites in wildlife (wolves [Canis lupus] and ungulates; Chapters 2 and 3), domestic dogs (Canis familiaris; Chapters 4 and 5), and people (Chapters 6-8). Using a One Health framework, we also explored parasite control practices and potential policy solutions for rural and remote communities (Chapters 8 and 9). During post-mortem examination, we observed E. canadensis in approximately 11% (11/105) of elk [Cervus canadensis], and 21% (34/165) of wolves. Our examination of historical post-mortem reports of ungulates demonstrated that E. canadensis is distributed throughout Canada, except for the high Arctic islands, the Maritime provinces, and the island of Newfoundland. Our analysis of dog feces collected throughout Saskatchewan suggested that patent taeniid (Taenia or Echinococcus spp.) infection was rare (0-4%), and that rural and northern dogs had higher endoparasitism than urban dogs. Sero-surveillance for four zoonoses (E. canadensis, Toxoplasma gondii, Trichinella, and Toxocara canis) by enzyme-linked immunosorbent assay indicated similar results - that people in northern SK (65% of 201) had higher exposure to one or more parasites than those in southern SK (12% of 113). Using patient health records, we reported annual incidence rates for clinical illness for the following zoonotic parasites: echinococcosis – 1.4/1 000 000; toxoplasmosis- 1.7/1 000 000; and toxocariasis-0.06/1 000 000. In the final chapter we compared the cost of treating human echinococcosis cases with a prevention program based on dosing dogs with praziquantel at 6 week intervals in the Kelsey Trail region, where human incidence is highest. Based on direct healthcare costs, such a program is not currently cost saving, but could become so if echinococcosis incidence increased. Preventative programs should be considered for high risk communities, which are often economically marginalized and lack appropriate resources to effectively control zoonotic parasitism. Putting One Health into action may require integrated human-animal healthcare services, introduction of community-based animal health workers, and increased transdisciplinary research to improve access to and uptake of preventative healthcare services for parasitic zoonoses in northern and remote communities.

Enterococcus faecium is a leading cause of hospital-acquired infection, disproportionally affecting immunocompromised and critically ill patients. Despite infection control measures, rates of vancomycin-resistant E. faecium (VREfm) bacteraemias have failed to decline in the United Kingdom, and Cambridge University Hospitals (CUH) report the highest numbers nationally. The aims of my PhD were to use epidemiological and genomic surveillance data to establish risk factors for acquisition and infection with E. faecium in patients at CUH, and to use a One Health approach to consider possible sources for hospital patients by relating bloodstream-associated isolates with those cultured from livestock and the environment in the same geographic region. A retrospective matched nested case control study was performed to determine risk factors for VRE bacteraemia relating to antibiotic exposure. 235 cases were matched to 220 controls for length of admission, year, specialty and ward type. Multivariable analysis demonstrated that duration of exposure to parenteral vancomycin, fluoroquinolones and meropenem were independently associated with VRE bacteraemia. This provides evidence for the importance of antimicrobial stewardship targeting high-risk antibiotics in patients at risk of VRE bacteraemia. VREfm bacteraemia may be complicated by disease recurrence. Whole genome sequencing was used to distinguish between relapse and reinfection in 14 episodes of recurrent VREfm bacteraemia. This demonstrated that 10 (71%) episodes were due to reinfection with a new strain, with reinfection being more likely with increasing time between two positive cultures. This study also evaluated 9 patients with blood cultures positive for both VREfm and vancomycin-susceptible E. faecium (VSEfm), the majority (78%) of which were found to be unrelated strains. More than half of all study isolates from these two patient groups were closely related to another isolate causing bacteraemia at CUH, suggesting that hospital acquisition of VREfm is a driver for infection and recurrence. A cross-sectional study of E. faecium in raw and treated wastewater from 20 municipal water treatment plants across the East of England revealed widespread dissemination of healthcare-associated lineages of VREfm in all sampled locations including rural areas, and environmental release in treated wastewater in 17/20 locations. Wastewater isolates were genetically intermixed with isolates causing bacteraemia at CUH, including highly related isolates indicating recent transmission between the two reservoirs. These findings are consistent with widespread distribution of healthcare-associated VREfm in community populations. A One Health approach incorporating sampling from livestock (10 pork, 10 cattle, 9 poultry farms) detected no VREfm in animals whilst 2 independent meat surveys demonstrated VREfm in 1-2% of uncooked products. Genomic comparison of >1400 E. faecium isolates from livestock, meat, wastewater and almost 800 people with bloodstream infection demonstrated that livestock and human isolates were genetically distinct. Analysis of the accessory genome added further evidence for distinct gene content associated with niche adaptation. An analysis of mobile genes encoding antibiotic resistance revealed limited evidence of sharing between human and animal populations. A prospective longitudinal study in haematology patients at CUH over 6 months revealed high rates of VREfm carriage (63% of cases) and environmental contamination (49% of samples). Genomic analysis elucidated complex colonisation dynamics with frequent loss and acquisition of subtypes, including unsuspected acquisition of new VREfm subtypes in patients already colonised with VREfm, and multiple transmission chains involving patients and the environment, including some leading to bacteraemia. These findings highlight the shortcomings of infection control and environmental cleaning and provide the basis for revised interventions.

Livestock production is central to the livelihoods of millions of people in Nigeria, and indeed across the continent. Understanding how livestock based economies function and the issues that constrain them has long been an important task for actors interested in supporting rural development. In recent years, the One Health agenda has provided a new impetus for studying and tackling the interconnections between human, animal and environmental. Whilst this is welcome, it tends to be selective in its modus operandi of intersectoral collaboration as advocated. This new risk repeats the tendencies of earlier scholarship in understanding rural animal production systems as a vertical system. In particular, gender analysis of addressing the growing threats of neglected tropical diseases (NTDs) is lacking in One Health as evidenced in the findings from the study areas of Kachia Grazing Reserve and the Jos Plateau. There is thus a need to illustrate the importance of integrating gender equality into the One Health concept of programmes especially in pastoralist areas. Through the use of a qualitative approach of eliciting needed information by the use of a range of qualitative methods at the community and household levels, this thesis, based on three case studies provides substantial new empirical contributions to this debate. Specificially, chapter four, by exploring the strategies employed by the study population to cope with, as well as to build their resilience to the inadequacies of the Kachia Grazing Reserve, argues that these inadequacies affect gender, gender relations, and livelihoods. As a reinforcement to these assertions, chapter five explores the role of women self help groups in the KGR and argues that these self help groups could be used as instruments in propelling the One Health concept in pastoral areas like that of the KGR. Lastly, chapter six explores the effect of conflict and violence on gender, gender relations and livelihoods in the Jos Plateau and examines how timely and effective delivery of One Health could act as a conflict resolution in conflict and violence inflicted pastoralist areas of the Jos Plateau. This thesis, in a way, gives possible explanation to the reticence of gender in One Health. Thus, in recognition of the potentials of the One Health concept, and in considering the realities on ground and the importance of integrating gender equality in its programme planning and delivery, the analysis of data from the three case studies of this thesis brings into focus the ‘how’ and ‘why’ of gender analysis affects delivery of One Health programmes in local pastoralists communities.

Introduction: Carbapenems and colistin are the last-line antibiotics for treating Gram-negative bacterial infections. However, increasing reports of resistance to these antibiotics is being reported in clinical settings, the environment and in animals. In this paper, we describe the molecular epidemiology and resistance mechanisms of colistin and carbapenem resistance in clinical, veterinary, and environmental Enterobacterales isolates in Pretoria, South Africa. Method: One hundred VITEK®-2-confirmed colistin and carbapenem-resistant clinical isolates were collected from the departmental isolate bank at the National Health Laboratory Service. A total of 88 porcine (stool) and 11 environmental (effluents) samples were collected in November 2018 and again in March 2019 from a farm in Pretoria. Both the porcine and environmental samples were screened using Eosin methylene blue agar with colistin and ertapenem disks. All isolates were identified and a minimum inhibitory concentration of colistin and carbapenems was determined using the MicroScan® WalkAway system. Isolates resistant to colistin were confirmed by the broth microdilution method. Isolates phenotypically resistant to colistin and carbapenems were selected for whole genome sequencing to determine the resistome and phylogenetic trees were drawn to determine the relatedness of isolates. Results: A total of 275 Gram-negative isolates were identified from the clinical (100), environmental (57) and veterinary (118) samples using the MicroScan® WalkAway system. The MicroScan® WalkAway system’s minimum inhibitory concentration results for clinical isolates revealed 88% and 93% resistance to colistin and carbapenems, respectively. BMD was found to be more reliable in all isolates, and it recorded higher MICs (increased resistance) than the MicroScan® WalkAway system. Overall, colistin susceptibility was higher among animal isolates compared to the clinical and environmental samples. Genomic analysis identified several resistance genes associated with resistance among the isolates and the CTX-M family were the dominant resistance genes. Phylogenomic analysis demonstrated closer evolutionary relationship between EB008 (environment), SW10B (animals), and C080 and C084 (both humans) strains as well as with strains from the United States of America, Canada, China, Russia and Durban (South Africa). Conclusion: The study established multiple resistance genes from different antibiotics to mediate resistance in Enterobacterales isolates from humans, animals and the environment. The presence of carbapenemases in animals is alarming and poses a public health concern. Strains EB008 (environment), SW10B (animals) and C080 and C084 (both human) were phylogenetically related with strains from the United States of America, China and Durban (South Africa) more commonly. Therefore, One Health approach studies are significant to ascertain colistin and carbapenem transmission from human to animals/the environment and vice versa to combat increasing resistance in Enterobacterales. / Dissertation (MSc)--University of Pretoria, 2020. / National Research Foundation (NRF) / National Health Laboratory Service research grant / Medical Microbiology / MSc / Unrestricted

Linhagens de Escherichia coli produtoras de β-lactamase de espectro estendido (ESβL) do tipo CTX-M são endêmicas no Brasil, sendo prevalentes em casos de infecções hospitalares e ambulatoriais. Atualmente, cepas produtoras de CTX-M têm sido recuperadas de ambientes urbanos, animais de companhia ou de produção e de alimentos de origem animal, inclusive afetando o agronegócio, o que aponta uma possível rota de disseminação em diferentes ecossistemas. Recentemente, nesta espécie, foi descoberto um novo gene, chamado de mcr-1, que confere resistência transferível à colistina, um dos últimos antibióticos eficazes para o tratamento de infecções causadas por bactérias produtoras de ESBL e carbapenemases. Deste modo, o presente estudo tem como objetivo elucidar os aspectos sobre a caracterização e a relação de plasmídeos que carregam genes do tipo blaCTX-M-8 e mcr- 1 em cepas de E. coli isoladas de seres humanos, animais, ambiente aquático e alimentos, no Brasil. Neste estudo são apresentados os resultados da análise plasmidial de 25 cepas de E. coli, das quais nove apresentaram o genótipo blaCTX-M-8/IncI1, 11 apresentaram o genótipo mcr-1/IncX4 e cinco apresentaram ambos os genótipos blaCTX-M-8/IncI1 e mcr-1/IncX4. Dos resultados, podemos observar que plasmídeos IncI1 (blaCTX-M-8) e IncX4 (mcr-1) estão circulando no Brasil desde o ano de 2009 entre diferentes clones (STs) de E. coli e em diferentes ambientes e hospedeiros. Os plasmídeos IncI1 foram conjugativos e pertencentes ao ST113, exceto o plasmídeo recuperado de um isolado humano, que foi pertencente ao ST131. Os plasmídeos IncI1 apresentaram sua arquitetura conservada, com a presença de genes de replicação, transferência e estabilidade. A partir do alinhamento, os plasmídeos IncI1 apresentaram 94-99% de similaridade genética entre eles. Dentre os plasmídeos IncX4, independente da fonte de isolamento, todos permaneceram com sua arquitetura altamente conservada. Entretanto, apenas dois plasmídeos (um encontrado em uma cepa de animal e outro encontrado em uma cepa de ambiente aquático) apresentaram uma IS1294, truncando o gene de mobilização. Na análise comparativa, todos os plasmídeos IncX4 apresentaram similaridade genética de 95-99,9% entre eles. No alinhamento de plasmídeos IncX4 brasileiros contra plasmídeos de outras regiões geográficas, foi observada similaridade genética > 99,9%, o que confirma a estabilidade e conservação desses plasmídeos. Neste estudo foram reportados dados inéditos da primeira identificação do gene mcr-1 em diferentes ecossistemas no Brasil, assim como a nova variante mcr-5.3. A análise filogenética dos plasmídeos IncI1 e IncX4, destacam que ambos compartilham uma arquitetura conservada, e a evolução é atribuída à aquisição de genes de resistência. Adicionalmente, um novo vetor de disseminação do gene mcr-1 no Brasil foi identificado - o plasmídeo IncHI2. Os resultados desse estudo demonstram o grave problema da resistência bacteriana dentro do conceito One-health e que, com o avanço de ferramentas moleculares, a identificação e a resolução desse problema poderá estar cada vez mais próxima de ser elucidada. / CTX-M-type extended-spectrum-β-lactamase (ESβL)-producing-Escherichia coli are endemic in Brazil and are prevalent in cases of nosocomial and ambulatory infections. Currently, CTXM-producing strains have been recovered from urban environments, companion/production animals and animal source foods, which indicates a possible route of dissemination in different ecosystems. Recently, in this species, a new gene, called mcr-1, has been discovered, conferring transferable resistance to colistin, one of the last effective antibiotics for the treatment of infections caused by ESBL- and carbapenemases -producing bacteria. Thus, the present study aims to elucidate unknown aspects of the pan-resistome and ancestral relationship of plasmids carrying blaCTX-M-8 and mcr-1 genes in strains of E. coli isolated from humans, animals, aquatic environment and food, in Brazil. In this study, we present results from the plasmidial analysis of 25 E. coli strains, from which nine presented the blaCTX-M-8/IncI1 genotype, 11 presented the mcr-1/IncX4, and five presented both blaCTX-M-8/IncI1 and mcr-1/IncX4 genotypes. Among these results, we can observe that IncI1 (blaCTX-M-8) and IncX4 (mcr-1) plasmids are circulating in Brazil since 2009, between different E. coli clones (STs) and different hosts and environments. IncI1 plasmids were conjugative and assigned to ST113, with exception of a plasmid recovered from a human isolate, which was assigned to ST131. IncI1 plasmids presented conserved architecture, with the presence of genes of replication, transference, and stability. From the alignment analysis, IncI1 plasmids presented 94-99% genetic similarity among them. Among the IncX4 plasmids, regardless the isolation source, their architecture remained highly conserved. However, only two plasmids (one detected in an animal\'s strain and another detected in an aquatic environment\'s strain) presented an IS1294, truncating the mobilization gene. In the comparative analysis, all IncX4 plasmids presented 95-99,9% genetic similarity among them. In the alignment of Brazilian IncX4 plasmids against plasmids from other geographic regions, >99.9% genetic similarity was observed, confirming the stability and conservation of these plasmids. In this study, unprecedented data from the first identification of the mcr-1 gene in different ecosystems in Brazil, as well as the new variant, mcr-5.3. Additionally, it was identified a new dissemination vector of the mcr-1 gene in Brazil - the IncHI2 plasmid. Phylogenetic analysis of IncI1and IncX4 plasmids highlight that both share a conserved backbone, and evolution is attributed to the acquisition of clinically relevant antimicrobial resistance genes. The results from this study demonstrate the serious problem of the bacterial resistance within the \"One-Health\" concept and that, with the advance of molecular tools, identification and resolution of this problem may be increasingly closer to being elucidate.

The global One Health movement has become firmly entrenched in both political and scientific discourse pertaining to emerging infectious diseases in the past decade. Since the discovery of the H5N1 strain of Highly Pathogenic Avian Influenza in Hong Kong in 1997, the promotion of more holistic programmes for the control of emerging infectious disease has garnered “unprecedented support” in terms of donor funding and political mobilisation (Scoones 2010). Advocates of One Health argue that intersectoral approaches promoting better communication between the veterinary, medical and environmental disciplines at all levels of governance make not only sound economic sense, they are fundamental to the “new approach” required to address the growing disease threats of the 21st century. However, despite international endorsement of the One Health rhetoric, there is growing pressure to now “turn the rhetoric into reality” (Okello et al 2011). Using a multiple, embedded case study methodology, this thesis seeks to examine questions surrounding the practical implementation of One Health interventions, particularly in developing countries which experience limited resources and competing health priorities. Through examining the livestock and public health policy processes at both local and national levels in Uganda and Nigeria, I attempt to identify whether policy spaces exist for the formal inclusion of One Health approaches in future policy decisions. Furthermore, by scrutinising the current internationally dominant One Health narratives in light of global health governance perspectives and the emerging One Health Global Network, I question whether One Health can be better “packaged” to include endemic diseases and a more focussed sustainable livelihoods approach; arguably inciting greater motivation for developing countries to truly participate. Data from my three empirical chapters are presented in the context of three overriding “One Health propositions” for consideration; by questioning “whose world, whose health”, I aim to delve further into the issues of not whether, but how this “new health paradigm” can be operationalised, and how to address the potential gaps which may ultimately prevent One Health from becoming a truly global phenomenon.

The work presented focuses on bacterial zoonoses in northern Nigeria, and more specifically on brucellosis in the Kachia grazing reserve (KGR) - rangeland set-aside by the government to sedentarise Fulani pastoralists. The objectives of the study were to 1) undertake demographic and socioeconomic profiling of the KGR community; 2) review the evidence for brucellosis burden in Nigeria; 3) assess the suitability and performance of brucellosis diagnostic tests selected for use; 4) compare burden of brucellosis across different species (animal and human) and determine Brucella species present in KGR; 5) explore social or environmental factors which may promote or prevent brucellosis transmission; 6) make recommendations for brucellosis control in the KGR and Nigeria; 7) explore community perception of disease and determine household expenditure on animal health; 8) critically evaluate the system’s, integrated, disease cluster, ‘One Health’ approach applied in this study. Three surveys comprising animal (cattle, sheep and goat) and human sampling, administration of questionnaires, focus group discussions and key informant interviews were undertaken in March, June and October 2011. A population census was undertaken in June 2011. Comparison of 2010 government census data with June 2011 census data showed that a mass immigration event occurred in April-May 2011 as a result of post-election violence, with cattle and human populations increasing by 75%. Questionnaire and census data demonstrated the diversity and heterogeneity of the Fulani community in terms of wealth status (roughly corresponding to livestock assets), household size and composition and livelihood diversification strategies. While Fulani in grazing reserves were assumed to be sedentary, KGR households were found to practice wide-range dry and wet season transhumance. Cattle productivity parameters and herd dynamics were similar to those reported by other authors for the extensive pastoralist systems in the sub-humid zone. Herd increase over a one-year period was found to be low or negative for most households in this low input, low output system. Brucellosis epidemiology in the KGR involves B. abortus biovar 3a with low individual and moderate cattle herd prevalence and occasional spill-over into small ruminants. No human brucellosis was detected despite over 80% of the KGR population consuming raw milk and engaging in risky behaviours, raising questions about the potential lower virulence of the local biovar. Low infection rates in livestock, disease-reducing intuitive behaviours or immunity may also be at play. The RBT was found to perform well under field conditions, despite poor concordance when applied in different laboratories and under different conditions. Prospects for control/elimination of brucellosis in the KGR are poor, but low animal burden and absence of human disease render vaccination uneconomic. A review of the literature in Nigeria suggests that brucellosis burden is higher in intensive livestock production systems, which should be targeted first. A laissez-faire approach to brucellosis control in the nomadic pastoralist domain may appeal to policy-makers, as interventions in migratory populations are difficult. Brucellosis is perceived by the KGR community as the number three-priority disease, after trypanosomiasis and Fasciola gigantica/clostridial infection and this was reflected in household expenditure on chemotherapeutics and prophylaxis. Finally, the value of the One Health approach is the ability to see the whole picture, including disease impacts in the animal reservoir as well as the human population, without which erroneous epidemiological and economic conclusions may be drawn; for example, presence of brucellosis in the animal reservoir does not necessarily indicate presence of human disease. This work shows that moving from disciplinary silos to a more holistic or system’s approach spanning epidemiology, evaluation of diagnostic and control tools as well as socio-economic, cultural and institutional aspects can lead to more appropriate recommendations for disease control.

Campylobacter spp. infections are an increasing global concern responsible for a significant burden of disease every year. Wildlife and domestic animals are considered important reservoirs, but little is known about host-factors driving pathogen infection dynamics in wild mammal populations. In countries like Botswana, there is significant spatial overlap between humans and wildlife with a large proportion of the population vulnerable to Campylobacter infection, making Botswana an ideal location to study these interactions. This thesis reviews mammalian wildlife species that have been identified as carriers of Campylobacter spp., identifies life-history traits (urban association, trophic level, and sociality) that may be driving Campylobacter infection, and utilizes banded mongoose (Mungos mungo) (n=201) as a study species to illuminate potential Campylobacter spp. transmission at the human-wildlife interface in northern Botswana. Results of the latter study suggest that human-landscapes are critical to C. jejuni infection in banded mongooses, as mongooses utilizing man-made structures as dens had significantly higher levels of C. jejuni than mongooses using natural dens (p=0.019). A similar association was found across all wild mammals with significantly greater number of urban dwelling species positive for C. jejuni than urban avoiders (p = 0.04). Omnivorous and social mammals were significantly associated with C. coli presence (p=0.04 and p<0.00 respectively), but not with C. jejuni indicating there may be important differences in transmission dynamics between Campylobacter species. These results suggest that landscape features and life-history traits can have important influences on Campylobacter species exposure and transmission dynamics in wildlife. / Master of Science / Campylobacter infections are increasing worldwide but we still know little about the true burden of disease in the developing world, and even less about the role of wildlife and environmental reservoirs in human exposure and disease. I reviewed life-history traits (urban association, animal rank on the food chain, and sociality) that might be driving Campylobacter spp. infection in wildlife and investigated interactions between an urbanizing wildlife species, banded mongoose (Mungos mungo), humans, and the environment. Banded mongooses live in close association with humans and infections with C. jejuni were greater among mongooses utilizing man-made structures compared to those using natural dens. Across all wild mammal species tested for Campylobacter spp., mammals associated with urban living were significantly more likely to be positive for C. jejuni than mammals that avoid urban areas. Lowerranking mammals on the food chain and social mammals were associated with presence of C. coli, suggesting life-history rates are playing a role in wild mammal exposures to the pathogen and that these exposures are different for C. coli than C. jejuni. These data suggest that wildlife life-history traits and utilization of human landscapes are important for pathogen presence. In turn, pathogen circulation and transmission in urbanizing wildlife reservoirs may increase human vulnerability to disease, particularly in impoverished populations, where greater environmental exposures are expected. Improvement of waste management and hygiene practices may help reduce transmission between wildlife and humans.

Dans une perspective comparative entre la France et les États-Unis, ce travail analyse le processus de publicisation des liens entre l’antibiorésistance et l’alimentation, ainsi que ses implications en termes de contribution au développement de la production appelée sans antibiotique et de l’approche One Health. En partant de la prise de conscience des conséquences de l’usage des antibiotiques dans l’élevage, la recherche s’inscrit dans une réflexion pragmatiste de constitution des problèmes publics et s’appuie sur un corpus hybride composé de documents publiés entre 1980 et 2016 (presse écrite, littérature institutionnelle et entretiens semi-directifs). La méthode développée s’enrichit des outils de textométrie issus de l’analyse de discours et s’intéresse à l’émergence des dénominations et des formules qui nomment le problème, ses causes et ses solutions. La comparaison montre que le processus de publicisation de liens entre l’antibiorésistance et l’alimentation dévoile une trajectoire opposée dans les deux pays. Dans le cas français, ce processus s’inscrit dans un schéma top-down et se caractérise par une publicisation tardive faisant suite aux démarches des instances sanitaires européennes et internationales. L’appropriation du problème par des associations de consommateurs, ainsi que l’investissement des acteurs agroalimentaires dans le développement de la production sans antibiotique, n’émergent que récemment. En revanche, aux États-Unis, ce processus s’inscrit dans un modèle bottom-up suite à la constitution d’un public d’organisations non gouvernementales autour du problème. Leur mobilisation a contribué significativement au développement de programmes d’élevage sans antibiotique ainsi qu’à la mise à l’agenda gouvernemental du problème et le lancement d’un plan national dans une approche One Health. / In a cross-country perspective between France and the United States, this research analyses the process of publicizing the links between antibiotic resistance and food, as well as its contribution to the development of the antibiotic free production and the implementation of the One Health approach. Starting with the awareness of the antibiotic use in livestock consequences, the study relies on the pragmatist approach of the constitution of the public problems. It is based on wide corpora composed by documents published between 1980 and 2016 (written press, institutional literature and semi-directive interviews). The analysis method uses textometric tools derived from discourse analysis and focuses on the emergence of formulas that name the problem, its causes and its solutions. The comparison uncovers an opposite process between the two countries. In France, this process is part of a top-down approach and is characterized by a late publicization following the European and international health authorities’ initiatives. The consumer associations taking over the problem, as well as the agri-food actors’ commitment to the antibiotic free production, is very recent. In the United States, this process reveals a bottom-up model following a non-governmental organizations public constitution taking over the problem. Their mobilization has contributed to the development of the antibiotic free breeding programs, as well as to place the problem on the government agenda that launched a national plan in a One Health approach.