23S rRNA and L22 ribosomal protein are involved in the acquisition of macrolide and lincosamide resistance in Mycoplasma capricolum subsp. capricolum

© 2018. Elsevier. This document is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This document is the Accepted version of a Published Work that appeared in final form in Veterinary Microbiology. To access the final edited and published work see https://doi.org/10.1016/j.vetmic.2018.02.014Mycoplasma capricolum subsp. capricolum (Mcc) is one of the causative agents of contagious agalactia, and antimicrobial treatment is the most commonly applied measure to treat outbreaks of this disease. Macrolides and lincosamides bind specifically to nucleotides at domains II and V of the 23S rRNA gene. Furthermore, rplD and rplV genes encode ribosomal proteins L4 and L22, which are also implicated in the macrolide binding site. The aim of this work was to study the relationship between these genes and the acquisition of macrolide and lincosamide resistance in Mcc. For this purpose, in vitro selected resistant mutants and field isolates were studied. This study demonstrates the appearance of DNA point mutations at the 23S rRNA encoding genes (A2058G, A2059G and A2062C) and rplV gene (Ala89Asp) in association to high minimum inhibitory concentration values. Hence, it proves the importance of 23S rRNA domain V and ribosomal protein L22 as molecular mechanisms responsible for the acquisition of macrolide and lincosamide resistance in both field isolates and in vitro selected mutants. Furthermore, these mutations enable us to provide an interpretative breakpoint of antimicrobial resistance for Mcc at MIC 0.8 µg/ml

Zoonoses and pets in domestic environments: risk communication

En las sociedades occidentales, la tenencia de mascotas en el hogar se incrementa anualmente debido a los beneficios emocionales, físicos y psíquicos que aportan. Junto a estos beneficios, debe considerarse también la existencia de diferentes enfermedades que pueden transmitirse desde los animales al resto de convivientes en el hogar, con especial importancia para aquellas personas pertenecientes a grupos de riesgo. El aparente desafío riesgo-beneficio que provoca la tenencia de mascotas deberá solventarse considerando el estado de salud de los miembros del hogar para la selección de la especie y la recomendación de medidas higiénicas y de manejo específicas. De forma general, el conocimiento y la preocupación de los propietarios por las zoonosis asociadas a sus mascotas son escasos, incluso en los hogares donde hay personas de alto riesgo. Además, las limitaciones en los procedimientos de comunicación con los diferentes profesionales sanitarios pueden ocasionar que las situaciones de riesgo pasen desapercibidas. Por todo ello, se impone la necesidad de establecer protocolos, tanto intra como interprofesionales, para proporcionar un adecuado flujo de información que asegure la comunicación con el propietario de acuerdo con las particularidades sanitarias de los convivientes de cada hogar.In occidental societies, the presence of pets in households increases year after year as a result of their beneficial effects on emotional, physical and psychological aspects. Along with these benefits, the existence of different diseases that can be transmitted from the animals to the rest of the members of the household must be taken into consideration, especially for those co-habitants who belong to the population at risk. This apparent challenge between the risks and benefits of pet ownership ought to be settled by taking into account the health status of the different members of the household in order to select the most convenient animal species as well as to determine the specific hygienic and management measures to apply. In general, the knowledge and concern of pet owners regarding the zoonoses associated to their pets are scarce, even when members of their household are considered as population at risk. In addition, the limitations affecting the communication procedures from the different health professionals may cause risk situations to pass by unnoticed. For this reason, it is necessary to establish interprofessional and intraprofessional protocols which ensure an adequate communication flow with pet owners depending on the particular health situation of their households

Mecanismos moleculares de resistencia antibiótica y papel epidemiológico del semental ovino en la agalaxia contagiosa

Los artículos que conforman la presente tesis doctoral por compendio abordan, por un lado, el papel del semental ovino en la epidemiología de la agalaxia contagiosa y por otro, el estudio de los mecanismos moleculares responsables de la resistencia a macrólidos, lincosamidas y tetraciclinas en los micoplasmas causantes de esta enfermedad. El objetivo común de ambos aspectos es mejorar las estrategias de control y prevención aplicadas frente a la agalaxia contagiosa. Más concretamente, los objetivos y la metodología seguida en la presente tesis doctoral son: 1) Estudiar la excreción de Mycoplasma agalactiae, el principal agente causal de la agalaxia contagiosa, en el semen de moruecos asintomáticos naturalmente infectados; 2) Determinar la muestra más eficaz para detectar la presencia de moruecos infectados por M. agalactiae en colectivos de sementales presentes en centros de inseminación; 3) Realizar una revisión bibliográfica acerca de otras micoplasmosis emergentes de los pequeños rumiantes que cursan con sintomatología similar a la de la agalaxia contagiosa; 4) Evaluar la susceptibilidad antimicrobiana y dilucidar el papel de las mutaciones en el ARN ribosómico 23S y las proteínas ribosomales L4 y L22 en la resistencia a macrólidos y lincomicina en aislamientos de campo y mutantes seleccionados in vitro de M. agalactiae; 5) Investigar el efecto de mutaciones en el ARN ribosomal 23S y las proteínas ribosomales L4 y L22 en el descenso de la susceptibilidad de aislamientos de campo y mutantes seleccionados in vitro de M. capricolum subsp. capricolum a macrólidos y lincosamidas; 6) Determinar y comparar la susceptibilidad a las tetraciclinas de aislamientos de campo con distintas características epidemiológicas de las cuatro especies de micoplasma causantes de la agalaxia contagiosa y 7) Investigar los mecanismos moleculares responsables del descenso de susceptibilidad a las tetraciclinas en dichos agentes patógenos. Los resultados obtenidos permiten concluir que: 1) M. agalactiae es excretado de forma intermitente en el semen de moruecos asintomáticos naturalmente infectados; 2) Hay moruecos portadores infectados por M. agalactiae en todos los centros de inseminación artificial estudiados; 3) El semen y los hisopos nasales son las muestras más eficaces para detectar moruecos asintomáticos infectados por M. agalactiae; 4) Se observa una tendencia creciente en la resistencia a la tilosina en los aislamientos de campo actuales de M. agalactiae; 5) Las mutaciones causantes de alteraciones en el ARN ribosomal 23S y la proteína ribosomal L22 son los mecanismos moleculares responsables de la resistencia a macrólidos y lincosamidas en M. agalactiae y en M. capricolum subsp. capricolum; 6) Los resultados de susceptibilidad a tetraciclinas de los micoplasmas causantes de la agalaxia contagiosa son tranquilizadores, si bien M. agalactiae es la especie menos susceptible y la resistencia a estos antibióticos se está desarrollando actualmente en el campo y 7) Las mutaciones que alteran el ARN ribosomal 16S no se asocian de forma evidente al descenso de susceptibilidad a tetraciclinas en los micoplasmas causantes de la agalaxia contagiosa estudiados, lo que sugiere la existencia de otros mecanismos de resistencia antibiótica.The present doctoral thesis is formed by six scientific articles which address the epidemiological role of rams in contagious agalactia and the molecular mechanisms behind the resistance of the etiological agents of this disease to macrolides, lincosamides and tetracyclines. The common goal of these subjects is to improve the preventive and control strategies of contagious agalactia. More specifically, the aims and methodology followed in the present doctoral thesis are: 1) To study the excretion of Mycoplasma agalactiae, the main causative agent of contagious agalactia, in the semen of naturally infected asymptomatic rams; 2) To determine the most efficient sample to detect carrier rams infected with M. agalactiae in flocks housed in artificial insemination centres; 3) To review recently published literature on other emergent mycoplasmoses of small ruminants whose symptoms are also associated to contagious agalactia; 4) To assess the antimicrobial susceptibility and the role of mutations altering the 23S ribosomal RNA and ribosomal proteins L4 and L22 in the acquisition of macrolide and lincomcyn resistance of field isolates and in vitro selected mutants of M. agalactiae; 5) To investigate the effect of mutations in the genes encoding 23S ribosomal RNA and ribosomal proteins L4 and L22 on the loss of susceptibility of field isolates and in vitro selected mutants of M. capricolum subsp. capricolum to macrolides and lincosamides; 6) To determine and to compare the tetracycline susceptibility of field isolates with different epidemiological features of the four mycoplasma species responsible for contagious agalactia and 7) To investigate the molecular mechanisms behind the decreased susceptibility to tetracyclines of contagious agalactia causative mycoplasmas. The obtained results allowed concluding that: 1) M. agalactiae is excreted intermittently in semen of asymptomatic naturally infected rams; 2) There are asymptomatic rams infected with M. agalactiae in all the studied artificial insemination centres; 3) Semen and nasal swabs are the most effective samples to detect asymptomatic rams infected with M. agalactiae; 4) An increasing development of resistance to tylosin can be observed in current field isolates of M. agalactiae; 5) Mutations altering 23S rRNA and ribosomal protein L22 are the molecular mechanisms responsible for resistance to macrolides and lincosamides in M. agalactiae and M. capricolum subsp. capricolum; 6) The results of tetracycline susceptibility of the four contagious agalactia causative mycoplasma species are reassuring, although M. agalactiae is the less susceptible species and resistance to these antibiotics is currently emerging in the field and 7) There is no simple relationship between mutations in the 16S rRNA encoding genes and decreased susceptibility to tetracyclines in the studied contagious agalactia causative mycoplasmas, which suggests the existence of other resistance mechanisms

Mycoplasma excretion in reproductive male and female goats

Three experiments were designed in order to study the excretion routes of mycoplasmas involved in caprine contagious agalactia in chronically infected goat populations. The results obtained for external auricular canal (EAC) swabs were compared to other samples: 1) nasal swabs in 95 bucks; 2) conjunctival swabs in 85 bucks; 3) milk and vaginal swabs in 23 goats. Serology to detect specific antibodies against Mycoplasma agalactiae (Ma) was also conducted. Out of 1061 samples, the presence of Ma, Mmc and Mcc was detected in 23, 18 and 8 samples, respectively, which belonged to 24 bucks and 7 goats. EAC analyses detected 21 bucks (87.5%) and 4 infected goats (57.1%). Additional sampling (conjunctival, nasal swabs and vaginal swabs in goats) allowed the detection of further infected animals, in comparison to the sole sampling of the EAC

Zoonosis y salud laboral en la profesión veterinaria

ABSTRACT The veterinary profession implies a greater risk of infection by zoonotic pathogens than the overall population. The aim of the present work was to evaluate the impact of zoonoses on the occupational health of veterinarians reviewing the published surveys addressing this subject. Following these inquiries, between 4% and 64.3% of the surveyed professionals acknowledge to have suffered at least one zoonotic disease, and dermatophytosis is the most frequently described zoonosis. In addition, from a qualitative point of view, it is necessary to highlight the occurrence of different diseases of important clinical seriousness and the existence of infections by antimicrobial-resistant pathogens. Due to the absence of updated studies in Spain, the present work reflects on the need to recognize the health determinants associated to the veterinary profession within the characteristics of our labour market. The available data suggest that the occurrence of zoonoses as occupational diseases is underestimated in Spain. Therefore, performing surveys on occupational health, documenting and publishing cases and reviewing the risks and the impact of zoonotic diseases on the veterinary profession would contribute to the description and notification of such diseases on behalf of the healthcare administration and would also become an essential tool in occupational risk prevention.RESUMEN La profesión veterinaria presenta mayor riesgo de infección frente a agentes patógenos de carácter zoonósico que la población general. Con el objetivo de valorar el impacto de las zoonosis, el presente trabajo revisa las encuestas publicadas sobre salud laboral en la profesión veterinaria. En dichas encuestas, el rango de profesionales que refieren haber padecido al menos una zoonosis oscila entre el 4% y el 64,3%, siendo la dermatofitosis la zoonosis comunicada con mayor frecuencia. Además, desde el punto de vista cualitativo, cabe destacar la comunicación de diferentes procesos de especial gravedad clínica, así como la existencia documentada de infecciones por agentes patógenos resistentes a los antimicrobianos. Dada la ausencia de estudios actualizados en España, se reflexiona sobre la necesidad de conocer los determinantes de salud asociados a las características del mercado laboral de la profesión en nuestro entorno. Los datos existentes sugieren que la consideración legal de enfermedad profesional para las zoonosis se encuentra infraestimada en nuestro país. Por todo ello, la realización de encuestas de salud laboral, la documentación y publicación de los casos, así como la revisión de los riesgos y el impacto de las zoonosis en la profesión veterinaria, pueden contribuir a la calificación y notificación de dichas enfermedades por parte de la administración sanitaria, al tiempo que suponen una herramienta fundamental en el ámbito de la prevención de riesgos laborales

Zoonoses in Veterinary Students: A Systematic Review of the Literature

<div><p>Background</p><p>Veterinary students face diverse potential sources of zoonotic pathogens since the first years of their academic degree. Such sources include different animal species and pathologic materials which are used at university facilities as well as commercial clinics, farms and other external facilities.</p><p>Objectives</p><p>The present study utilizes a systematic review of the literature to identify zoonoses described in veterinary students.</p><p>Data sources</p><p>Web of Science and PubMed.</p><p>Results</p><p>Of the 1,254 titles produced by the bibliographic search, 62 were included in this review. Whereas 28 of these articles (45.2%) described individual cases or outbreaks, the remaining 34 (54.8%) reported serological results. The zoonotic etiological agents described were bacteria, in 39 studies (62.9%), parasites, in 12 works (19.4%), virus, in 9 studies (14.5%) and fungi, in 2 (3.2%) of the selected articles. The selected literature included references from 24 different countries and covered the time period of the last 55 years.</p><p>Limitations</p><p>The fact that common cases of disease or cases of little clinical importance without collective repercussions are not usually published in peer-reviewed journals limits the possibility to reach conclusions from a quantitative point of view. Furthermore, most of the selected works (66.1%) refer to European or North American countries, and thus, the number of cases due to pathogens which could appear more frequently in non-occidental countries might be underestimated.</p><p>Conclusions/implications</p><p>The results of the present systematic review highlight the need of including training in zoonotic diseases since the first years of Veterinary Science degrees, especially focusing on biosecurity measures (hygienic measures and the utilization of the personal protective equipment), as a way of protecting students, and on monitoring programs, so as to adequately advise affected students or students suspicious of enduring zoonoses.</p></div

Zoonoses reported in veterinary students identified by the systematic literature review according to the agent, country, year and main quantitative and qualitative information summarized from the selected studies.

<p>Zoonoses reported in veterinary students identified by the systematic literature review according to the agent, country, year and main quantitative and qualitative information summarized from the selected studies.</p

Flowchart of the selection process for publications selected in this review.

<p>Flowchart of the selection process for publications selected in this review.</p