Risk factors associated withStreptococcus suiscases on pigfarms in Spain

Background Streptococcus suis can cause meningitis, polyarthritis and acute death in piglets. However, the risk factors associated with S. suis infection remain incompletely understood. Therefore, a longitudinal study was carried out, in which six batches from two Spanish pig farms with S. suis problems were repeatedly examined to determine possible risk factors. Methods A prospective case–control study was conducted, and potential risk factors were evaluated using mixed-effects logistic regression models. The explanatory variables included: (a) concomitant pathogens; (b) biomarkers associated with stress, inflammation and oxidative status; (c) farm environmental factors; and (d) parity and S. suis presence in sows. Three models were built to study the effect of these variables, including two to assess the risk factors involved in the subsequent development of disease. Results Risk factors for S. suis-associated disease included porcine reproductive and respiratory syndrome virus co-infection at weaning (odds ratio [OR] = 6.69), sow parity (OR = 0.71), haptoglobin level before weaning (OR = 1.01), relative humidity (OR = 1.11) and temperature (OR = 0.13). Limitations Laboratory diagnosis was done at the batch level, with individual diagnosis based on clinical signs only. Conclusions This study confirms the multifactorial nature of S. suis-associated disease, with both environmental factors and factors related to the host involved in disease development. Controlling these factors may, therefore, help prevent the appearance of disease.Program for Innovative Global Prevention of Streptococcus suis (PIGSs), from program Horizon 2020 of the European Commission. Carlos Neila-Ibáñez was funded by the same project, Grant/Award Number: 727966info:eu-repo/semantics/publishedVersio

Piglet innate immune response to Streptococcus suis colonization is modulated by the virulence of the strain

Streptococcus suis is a zoonotic pathogen of swine involved in arthritis, polyserositis, and meningitis. Colonization of piglets by S. suis is very common and occurs early in life. The clinical outcome of infection is infuenced by the viru‑ lence of the S. suis strains and the immunity of the animals. Here, the role of innate immunity was studied in cesareanderived colostrum-deprived piglets inoculated intranasally with either virulent S. suis strain 10 (S10) or non-virulent S. suis strain T15. Colonization of the inoculated piglets was confrmed at the end of the study by PCR and immunohis‑ tochemistry. Fever (≥40.5 °C) was more prevalent in piglets inoculated with S10 compared to T15 at 4 h after inocula‑ tion. During the 3 days of monitoring, no other major clinical signs were detected. Accordingly, only small changes in transcription of genes associated with the antibacterial innate immune response were observed at systemic sites, with S10 inducing an earlier response than T15 in blood. Local infammatory response to the inoculation, evaluated by transcriptional analysis of selected genes in nasal swabs, was more sustained in piglets inoculated with the virulent S10, as demonstrated by transcription of infammation-related genes, such as IL1B, IL1A, and IRF7. In contrast, most of the gene expression changes in trachea, lungs, and associated lymph nodes were observed in response to the nonvirulent T15 strain. Thus, S. suis colonization in the absence of systemic infection induces an innate immune response in piglets that appears to be related to the virulence potential of the colonizing strain.info:eu-repo/semantics/publishedVersio

Stochastic Assessment of the Economic Impact of Streptococcus suis-Associated Disease in German, Dutch and Spanish Swine Farms

The economic assessment of animal diseases is essential for decision-making, including the allocation of resources for disease control. However, that assessment is usually hampered by the lack of reliable data on disease incidence, or treatment and control measures, and that is particularly true for swine production diseases, such as infections caused by Streptococcus suis. Therefore, we deployed a questionnaire survey of clinical swine veterinarians to obtain the input data needed for a stochastic model to calculate the costs caused by S. suis, which was implemented in three of the main swine producing countries in Europe: Germany, the Netherlands and Spain. S. suis-associated disease is endemic in those countries in all production phases, though nursery was the phase most severely impacted. In affected nursery units, between 3.3 and 4.0% of pigs had S. suis-associated disease and the mortalities ranged from 0.5 to 0.9%. In Germany, the average cost of S. suis per pig (summed across all production phases) was 1.30 euros (90% CI: 0.53-2.28), in the Netherlands 0.96 euros (90% CI: 0.27-1.54), and in Spain 0.60 euros (90% CI: 0.29-0.96). In Germany, that cost was essentially influenced by the expenditure in early metaphylaxis in nursery and in autogenous vaccines in sows and nursery pigs; in the Netherlands, by expenditure on autogenous vaccines in sows and nursery pigs; and in Spain, by the expenditures in early metaphylaxis and to a lesser extent by the mortality in nursery pigs. Therefore, the differences in costs between countries can be explained to a great extent by the measures to control S. suis implemented in each country. In Spain and in Germany, use of antimicrobials, predominantly beta-lactams, is still crucial for the control of the disease.info:eu-repo/semantics/publishedVersio

Feed additives for the control of post-weaning Streptococcus suis disease and the effect on the faecal and nasal microbiota

Medicated feed is a common strategy to control the occurrence of Streptococcus suis disease in swine production, but feed additives may constitute an alternative to metaphylaxis. In a farm with post-weaning S. suis disease, the following additives were tested: lysozyme (Lys), medium chain fatty acids plus lysozyme (FA + Lys), FA plus a natural anti-inflammatory (FA + antiinf) and amoxicillin (Amox). During the course of the study, FA + antiinf and Amox groups showed lower prevalence of clinical signs compatible with S. suis disease than the rest of the groups. Piglets from the FA + antiinf group showed high diversity and richness in their nasal and faecal microbiota. Diet supplements did not have major effects on the faecal microbiota, where the genus Mitsuokella was the only differentially present in the FA + Lys group. In the nasal microbiota, piglets from FA + antiinf presented higher differential abundance of a sequence variant from Ruminococcaceae and lower abundance of an unclassified genus from Weeksellaceae. In general, we detected more significant changes in the nasal than in the feacal microbiota, and found that parity of the dams affected the microbiota composition of their offspring, with piglets born to gilts exhibiting lower richness and diversity. Our results suggest that additives could be useful to control post-weaning disease when removing antimicrobials in farms.info:eu-repo/semantics/publishedVersio

Risk factors associated with Streptococcus suis cases on pig farms in Spain

Altres ajuts: acords transformatius de la UABBackground: Streptococcus suis can cause meningitis, polyarthritis and acute death in piglets. However, the risk factors associated with S. suis infection remain incompletely understood. Therefore, a longitudinal study was carried out, in which six batches from two Spanish pig farms with S. suis problems were repeatedly examined to determine possible risk factors. Methods: A prospective case-control study was conducted, and potential risk factors were evaluated using mixed-effects logistic regression models. The explanatory variables included: (a) concomitant pathogens; (b) biomarkers associated with stress, inflammation and oxidative status; (c) farm environmental factors; and (d) parity and S. suis presence in sows. Three models were built to study the effect of these variables, including two to assess the risk factors involved in the subsequent development of disease. Results: Risk factors for S. suis-associated disease included porcine reproductive and respiratory syndrome virus co-infection at weaning (odds ratio [OR] = 6.69), sow parity (OR = 0.71), haptoglobin level before weaning (OR = 1.01), relative humidity (OR = 1.11) and temperature (OR = 0.13). Limitations: Laboratory diagnosis was done at the batch level, with individual diagnosis based on clinical signs only. Conclusions: This study confirms the multifactorial nature of S. suis-associated disease, with both environmental factors and factors related to the host involved in disease development. Controlling these factors may, therefore, help prevent the appearance of disease

Piglet innate immune response to Streptococcus suis colonization is modulated by the virulence of the strain

Streptococcus suis is a zoonotic pathogen of swine involved in arthritis, polyserositis, and meningitis. Colonization of piglets by S. suis is very common and occurs early in life. The clinical outcome of infection is influenced by the virulence of the S. suis strains and the immunity of the animals. Here, the role of innate immunity was studied in cesarean-derived colostrum-deprived piglets inoculated intranasally with either virulent S. suis strain 10 (S10) or non-virulent S. suis strain T15. Colonization of the inoculated piglets was confirmed at the end of the study by PCR and immunohistochemistry. Fever (≥40.5 °C) was more prevalent in piglets inoculated with S10 compared to T15 at 4 h after inoculation. During the 3 days of monitoring, no other major clinical signs were detected. Accordingly, only small changes in transcription of genes associated with the antibacterial innate immune response were observed at systemic sites, with S10 inducing an earlier response than T15 in blood. Local inflammatory response to the inoculation, evaluated by transcriptional analysis of selected genes in nasal swabs, was more sustained in piglets inoculated with the virulent S10, as demonstrated by transcription of inflammation-related genes, such as IL1B, IL1A, and IRF7. In contrast, most of the gene expression changes in trachea, lungs, and associated lymph nodes were observed in response to the non-virulent T15 strain. Thus, S. suis colonization in the absence of systemic infection induces an innate immune response in piglets that appears to be related to the virulence potential of the colonizing strain

Epidemiological and Pathological Studies for Streptococcus suis

Streptococcus suis és un important patogen porcí amb distribució mundial. Tot i habitar de manera natural a les vies respiratòries dels porcs, a vegades pot produir malaltia als garrins en el moment del deslletament, caracteritzada per artritis, meningitis i/o mort sobtada. És a més un patogen zoonòtic, particularment rellevant als països del sud-est asiàtic. En aquesta tesis s'ha fet una estimació de la prevalença i el cost de la malaltia associats a S. suis per a tres dels principals països productors de porc a Europa: Alemanya, Països Baixos i Espanya (Estudi I). Els nostres resultats mostren que la malaltia té una alta incidència en les explotacions porcines d'aquests països, amb diferències substancials en la prevalença i la mortalitat entre fases, i una major prevalença en la transició. Els costos van ser més elevats a Alemanya, seguit de Països Baixos i Espanya, i s'expliquen fonamentalment per les mesures aplicades per a prevenir o controlar S. suis (autovacunes i antimicrobians). Malgrat que els garrins són colonitzats per S. suis en el moment del naixement, només una part desenvolupa la malaltia posteriorment. S'han estudiat diferents factors tradicionalment associats amb l'aparició de la malaltia en dues explotacions porcines catalanes (Estudi II). L'estrès dels animals i una elevada humitat en maternitat, la presència del virus de la síndrome respiratòria i reproductiva porcina, la temperatura més baixa en transició, així com la menor paritat de les truges augmenten el risc de desenvolupar signes clínics associats a la malaltia. La susceptibilitat de l'hoste i la virulència de les soques de S. suis presents a les granges també juguen un paper molt important en l'aparició de la malaltia. S'ha estudiat la resposta immune innata contra S. suis en garrins nascuts per cesària i privats de calostre amb un desafiament per via intranasal amb una soca virulenta i una altra no virulenta de S. suis (Estudi III). Aquesta infecció va permetre observar per primera vegada la resposta davant la colonització en mucosa nasal, sang, pulmó, tràquea, fetge i melsa mitjançant anàlisi transcriptòmic. La resposta a la soca no virulenta de S. suis es caracteritzà per un control ràpid en el lloc d'inoculació. Per altra banda, la resposta inflamatòria local de la soca virulenta es va mantenir més temps en la mucosa nasal, demostrant que la resposta de l'hoste depèn de la virulència de la soca. Addicionalment, la soca virulenta es va detectar més profundament a l'interior de la làmina cribosa de l'os etmoides, observació que suggereix una ruta alternativa d'invasió per a S. suis. Els antimicrobians s'han fet servir com a eines per al control de la malaltia causada per S. suis, tanmateix, el seu ús comporta l'aparició i propagació de resistències. Per tal d'afrontar el repte de reduir l'ús d'antimicrobians en el bestiar, es va provar l'eficàcia protectora d'una barreja de probiòtics nasals davant un desafiament letal amb una soca virulenta de S. suis (Estudi IV). Els comensals, pertanyents als gèneres Rothia, Moraxella i una soca no virulenta de S. suis, es van seleccionar en funció de diferents criteris, com l'abundància relativa en garrins sans, la inhibició in vitro de S. suis o la capacitat d'adherència. Tot i la falta de diferències significatives entre els grups, els garrins inoculats amb una combinació de dues soques de Rothia i una altra de Moraxella mostraren la millor taxa de supervivència i menor gravetat de signes clínics i lesions després del desafiament. Aquests resultats estableixen les bases per a futurs estudis amb probiòtics nasals porcins, una alternativa en la prevenció de malalties degudes a patògens colonitzadors primerencs de les vies respiratòries.Streptococcus suis es un importante patógeno porcino con una distribución mundial. A pesar de ser un habitante natural de las vías respiratorias de los cerdos, en ocasiones puede causar en los lechones una enfermedad caracterizada por artritis, meningitis y/o muerte súbita. Es también un patógeno zoonótico, particularmente importante en los países del sudeste asiático. En la presente tesis se ha estimado la prevalencia y el coste de la enfermedad asociada a S. suis para tres de los principales países productores de cerdos de Europa: Alemania, Países Bajos y España (Estudio I). Nuestros resultados mostraron que la enfermedad tiene una alta incidencia, con diferencias sustanciales en la prevalencia y mortalidad entre fases productivas. Los costes fueron mayores en Alemania, seguido de Países Bajos y España, y se explicaron fundamentalmente por las medidas aplicadas para prevenir o controlar S. suis (autovacunas y antimicrobianos). A pesar de que los lechones son colonizados por S. suis en el momento del nacimiento, solo una parte desarrollan la enfermedad más tarde. Debido a ello, fueron estudiados diferentes factores que tradicionalmente se han asociado a la aparición de la enfermedad en dos explotaciones porcinas catalanas (Estudio II). El estrés de los animales y la humedad más elevada en maternidad, la presencia del virus del síndrome respiratorio y reproductivo porcino, la temperatura más baja en transición, así como la menor paridad de las madres, aumentaron el riesgo de desarrollar signos clínicos asociados con la enfermedad. La susceptibilidad del hospedador y la virulencia de las cepas de S. suis presentes en las granjas juegan también un papel importante en el desarrollo de la enfermedad. Se estudió la respuesta inmune innata contra S. suis en lechones nacidos por cesárea y privados de calostro mediante el desafío por vía intranasal con una cepa virulenta y otra no virulenta de S. suis (Estudio III). Se observó así por primera vez la respuesta frente a la colonización en mucosa nasal, sangre, pulmón, tráquea, hígado y bazo mediante análisis transcriptómico. La respuesta a la cepa no virulenta de S. suis se caracterizó por un rápido control en el sitio de inoculación. Sin embargo, para la cepa virulenta, la respuesta inflamatoria local se mantuvo más tiempo en la mucosa nasal, lo que demuestra que la respuesta del hospedador depende de la virulencia de la cepa. Además, la cepa virulenta se detectó más profundamente en el interior de la lámina cribosa del hueso etmoides, lo que sugiere una ruta alternativa de invasión. Los antimicrobianos han sido una de las herramientas utilizadas para el control de la enfermedad provocada por S. suis, no obstante, su uso conlleva la aparición y propagación de resistencias. Para afrontar el reto de reducir el uso de antimicrobianos en el ganado, se probó la eficacia protectora de una mezcla de probióticos nasales frente a un desafío letal con una cepa virulenta de S. suis (Estudio IV). Los comensales, pertenecientes a los géneros Rothia y Moraxella, y una cepa no virulenta de S. suis, se seleccionaron en función de diferentes criterios, como la abundancia relativa en lechones sanos, la inhibición in vitro de S. suis o su capacidad de adherencia. A pesar de la falta de diferencias significativas entre los grupos, los lechones inoculados con una combinación de dos cepas de Rothia y otra de Moraxella mostraron la mejor tasa de supervivencia y menor gravedad de signos clínicos y lesiones después del desafío. Estos resultados sientan las bases para futuros estudios con probióticos nasales porcinos, una alternativa en la prevención de enfermedades causadas por patógenos que son colonizadores tempranos de las vías respiratorias.Streptococcus suis is a major swine pathogen with a worldwide distribution. Despite being a natural inhabitant of the pig respiratory tract, it can sometimes cause disease in weaning piglets, characterized by arthritis, meningitis, and/or sudden death. It is also a zoonotic pathogen, particularly important in Southeastern Asian countries. The impact of the disease in porcine production seems to be significant, but there are no accurate estimations. In this thesis the prevalence and cost of the S. suis-associated disease were estimated for three of the main pig-producing countries in Europe: Germany, the Netherlands, and Spain (Study I). Our results showed that the disease is highly prevalent in pig farms in these countries, with substantial differences in prevalence and mortality between phases, and higher prevalence in the post-weaning period. Costs were higher in Germany, followed by the Netherlands and Spain, and they were essentially explained by the measures applied to prevent or control S. suis (autovaccines and antimicrobials), although the value of the animals that die because of the pathogen was also important in the post-weaning period. Pigs in commercial farms get colonized by S. suis early in life, but only a fraction of farms and pigs develop the disease later. Because of the endemic aspect of S. suis and the estimated prevalence, different factors that have traditionally been associated with the appearance of S. suis disease were studied in two Catalan farms (Study II). Results showed that animal stress and higher humidity before weaning, presence of porcine respiratory and reproductive syndrome virus, lower temperature after weaning, and lower parity of the dams increased the risk of developing the disease. Host susceptibility and the virulence of the strains present in the farms also play an important role in the development of the disease. The pig response against this early colonizer was studied in cesarean-derived colostrum-deprived piglets intranasally inoculated either with a virulent or a non-virulent S. suis strain (Study III). This infection allowed the observation for the first time of the innate immune response against the colonization in nasal mucosa, blood, lung, trachea, liver, and spleen by transcriptional analysis. On the one hand, the host response to the non-virulent S. suis strain was characterized by rapid control at the site of inoculation. On the other hand, the piglet local inflammatory response was maintained longer in nasal mucosa for the virulent strain, demonstrating that the host response depends on the virulence of the strain. In addition, the virulent strain was detected deep in the cribriform plate of the ethmoid bone, suggesting that this may be an alternative route of invasion for S. suis. Antimicrobials are one of the tools used for control of S. suis disease, with the consequent problems in the emergence and spread of resistances. Recently, the microbiota was identified as a factor involved in health. Thus, in order to face the current challenge of reducing the use of antimicrobials in livestock, the protective efficacy of a mixture of nasal probiotics was tested against a lethal challenge with a virulent S. suis strain (Study IV). Commensals, belonging to the genera Rothia, Moraxella and a non-virulent S. suis strain, were selected based on different criteria, such as relative abundant in healthy piglets or in vitro S. suis inhibition. Despite the lack of significant differences between groups, piglets inoculated with a combination of two Rothia and one Moraxella showed the best survival rate and less severe clinical signs and lesions after challenge. This study lays the groundwork for future studies with porcine nasal probiotics, an alternative to prevent the diseases caused by pathogens that are early colonizers of the upper respiratory tract

First Report of Streptococcus ruminantium in Wildlife: Phenotypic Differences with a Spanish Domestic Ruminant Isolate

Streptococcus ruminantium is a recent reclassification of the former Streptococcus suis serovar 33. Although knowledge about S. suis is extensive, information on S. ruminantium host range and pathogenic potential is still scarce. This bacterium has been isolated from lesions in domestic ruminants, but there are no reports in wild animals. Here, we provide information on lesions associated with S. ruminantium in Pyrenean chamois (Rupicapra pyrenaica) and domestic sheep from NE Spain, as well as phenotypic biopatterns and antimicrobial resistance (AMR) of the isolates. Overall, lesions caused by S. ruminantium were similar to those caused by S. suis, excluding polyserositis. Heterogeneity of the phenotypic profiles was observed within the S. ruminantium strains by VITEK-2, resulting in only two tests common to all S. ruminantium isolates and different from S. suis: Alpha-Galactosidase and Methyl-B-D-Glucopyranoside, both positive for S. suis and negative for S. ruminantium strains. Isolates from Pyrenean chamois were susceptible to all antimicrobials tested, except danofloxacin, whereas the domestic sheep isolate was resistant to tetracycline. In conclusion, S. ruminantium can cause infection and be associated with pathology in both wild and domestic ruminants. Due to its phenotypic diversity, a specific PCR is optimal for identification in routine diagnosis.info:eu-repo/semantics/publishedVersio

First Report of Streptococcus ruminantium in Wildlife : phenotypic Differences with a Spanish Domestic Ruminant Isolate

Streptococcus ruminantium is a recent reclassification of the former Streptococcus suis serovar 33. Although knowledge about S. suis is extensive, information on S. ruminantium host range and pathogenic potential is still scarce. This bacterium has been isolated from lesions in domestic ruminants, but there are no reports in wild animals. Here, we provide information on lesions associated with S. ruminantium in Pyrenean chamois (Rupicapra pyrenaica) and domestic sheep from NE Spain, as well as phenotypic biopatterns and antimicrobial resistance (AMR) of the isolates. Overall, lesions caused by S. ruminantium were similar to those caused by S. suis, excluding polyserositis. Heterogeneity of the phenotypic profiles was observed within the S. ruminantium strains by VITEK-2, resulting in only two tests common to all S. ruminantium isolates and different from S. suis: Alpha-Galactosidase and Methyl-B-D-Glucopyranoside, both positive for S. suis and negative for S. ruminantium strains. Isolates from Pyrenean chamois were susceptible to all antimicrobials tested, except danofloxacin, whereas the domestic sheep isolate was resistant to tetracycline. In conclusion, S. ruminantium can cause infection and be associated with pathology in both wild and domestic ruminants. Due to its phenotypic diversity, a specific PCR is optimal for identification in routine diagnosis

Sow vaccination with a protein fragment against virulent glaesserella (Haemophilus) parasuis modulates immunity traits in their offspring

Glaesserella (Haemophilus) parasuis, an early colonizer of the nasal cavity in piglets, is a highly heterogeneous species, comprising both commensal and virulent strains. Virulent G. parasuis strains can cause fibrinous polyserositis called Glässer's disease. Colostrum is a source of passive immunity for young piglets. When vaccinating sows, protective antibodies are transferred to their offspring through the colostrum. Here, sow vaccination was performed with a protein fragment, F4, from the outer membrane trimeric autotransporters VtaAs exclusively found in virulent G. parasuis. Piglets were allowed to suckle for 3 weeks, following which a challenge with two virulent strains of G. parasuis was performed. A group of nonvaccinated sows and their piglets were included as a control. Antibodies against F4 were confirmed using ELISA in the vaccinated sows and their offspring before the G. parasuis challenge. Compared to the control group, F4-vaccination also resulted in an increased level of serum TGF-β both in vaccinated sows and in their offspring at early time points of life. After the challenge, a lower body temperature and a higher weight were observed in the group of piglets from vaccinated sows. One piglet from the non-vaccinated group succumbed to the infection, but no other significant differences in clinical signs were noticed. At necropsy, performed 2 weeks after the virulent challenge, the level of surfactant protein D (SP-D) in bronchoalveolar lavage was higher in the piglets from vaccinated sows. Vaccination did not inhibit the nasal colonization of the piglets by the challenge strains