974 resultados para Zoonotic pathogens


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Rodents are important reservoirs for a large number of zoonotic pathogens. We examined the occurrence of 11 viral, bacterial, and parasitic agents in rodent populations in Austria, including three different hantaviruses, lymphocytic choriomeningitis virus, orthopox virus, Leptospira spp., Borrelia spp., Rickettsia spp., Bartonella spp., Coxiella burnetii, and Toxoplasma gondii. In 2008, 110 rodents of four species (40 Clethrionomys glareolus, 29 Apodemus flavicollis, 26 Apodemus sylvaticus, and 15 Microtus arvalis) were trapped at two rural sites in Lower Austria. Chest cavity fluid and samples of lung, spleen, kidney, liver, brain, and ear pinna skin were collected. We screened selected tissue samples for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, Leptospira, Borrelia, Rickettsia, Bartonella spp., C. burnetii, and T. gondii by RT-PCR/PCR and detected nucleic acids of Tula hantavirus, Leptospira spp., Borrelia afzelii, Rickettsia spp., and different Bartonella species. Serological investigations were performed for hantaviruses, lymphocytic choriomeningitis virus, orthopox viruses, and Rickettsia spp. Here, Dobrava-Belgrade hantavirus-, Tula hantavirus-, lymphocytic choriomeningitis virus-, orthopox virus-, and rickettsia-specific antibodies were demonstrated. Puumala hantavirus, C. burnetii, and T. gondii were neither detected by RT-PCR/PCR nor by serological methods. In addition, multiple infections with up to three pathogens were shown in nine animals of three rodent species from different trapping sites. In conclusion, these results show that rodents in Austria may host multiple zoonotic pathogens. Our observation raises important questions regarding the interactions of different pathogens in the host, the countermeasures of the host's immune system, the impact of the host–pathogen interaction on the fitness of the host, and the spread of infectious agents among wild rodents and from those to other animals or humans.

Relevância:

70.00% 70.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Paracoccidioides brasiliensis infections have been little studied in wild and/or domestic animals, which may represent an important indicator of the presence of the pathogen in nature. Road-killed wild animals have been used for surveillance of vectors of zoonotic pathogens and may offer new opportunities for eco-epidemiological studies of paracoccidiodomycosis (PCM). The presence of P. brasiliensis infection was evaluated by Nested-PCR in tissue samples collected from 19 road-killed animals; 3 Cavia aperea (guinea pig), 5 Cerdocyon thous (crab-eating-fox), 1 Dasypus novemcinctus (nine-banded armadillo), 1 Dasypus septemcinctus (seven-banded armadillo), 2 Didelphis albiventris (white-eared opossum), 1 Eira barbara (tayra), 2 Gallictis vittata (grison), 2 Procyon cancrivorus (raccoon) and 2 Sphiggurus spinosus (porcupine). Specific P. brasiliensis amplicons were detected in (a) several organs of the two armadillos and one guinea pig, (b) the lung and liver of the porcupine, and (c) the lungs of raccoons and grisons. P. brasiliensis infection in wild animals from endemic areas might be more common than initially postulated. Molecular techniques can be used for detecting new hosts and mapping `hot spot` areas of PCM.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

The presence of Salmonella enterica and serologic evidence of infection by Leptospira interrogans, were detected in the opossum Didelphis virginiana in a semi-urban locality of the Yucatán State, México. Ninety-one opossums were captured during the period April 1996 and May 1998. From a total of 17 feces samples, four Salmonella enterica subsp. enterica serotypes (Sandiego, Newport, Anatum, and Minnesota), and one Salmonella enterica subsp. arizonae serovar O44:Z4,Z23:- were isolated. Some opossums presented mixed infections. From 81 sera samples, four (4.9%) were positive to antibodies to Leptospira serovars pomona and wolfii. Both animals infected with Salmonella enterica and those serologically positive to Leptospira interrogans were captured in peridomestic habitat. Opossums infected with Salmonella enterica, were captured in dry season, and those seropositive to Leptospira interrogans during the rainy season. The implications of infection and reactivity of these zoonotic pathogens in D. virginiana in the Yucatan state are briefly discussed.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Clin Microbiol Infect 2011; 17: 1312-1322 ABSTRACT: This review considers the role of intracellular bacteria in adverse pregnancy outcomes, such as miscarriage, stillbirths, and preterm labour. The cause of miscarriage, stillbirth and preterm labour often remains unexplained. Intracellular bacteria that grow either poorly or not at all on media used routinely to detect human pathogens could be the aetiological agents of these obstetric conditions. For example, Listeria monocytogenes and Coxiella burnetti are intracellular bacteria that have a predilection for the fetomaternal unit and may induce fatal disease in the mother and/or fetus. Both are important foodborne or zoonotic pathogens in pregnancy. Preventive measures, diagnostic tools and treatment will be reviewed. Moreover, we will also address the importance in adverse pregnancy outcomes of other intracellular bacteria, including Brucella abortus and various members of the order Chlamydiales. Indeed, there is growing evidence that Chlamydia trachomatis, Chlamydia abortus and Chlamydia pneumoniae infections may also result in adverse pregnancy outcomes in humans and/or animals. Moreover, newly discovered Chlamydia-like organisms have recently emerged as new pathogens of both animals and humans. For example, Waddlia chondrophila, a Chlamydia-related bacterium isolated from aborted bovine fetuses, has also been implicated in human miscarriages. Future research should help us to better understand the pathophysiology of adverse pregnancy outcomes caused by intracellular bacteria and to determine the precise mode of transmission of newly identified bacteria, such as Waddlia and Parachlamydia. These emerging pathogens may represent the tip of the iceberg of a large number of as yet unknown intracellular pathogenic agents.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Pigs are very often colonized by Staphylococcus aureus and transmission of such pig-associated S. aureus to humans can cause serious medical, hygiene, and economic problems. The transmission route of zoonotic pathogens colonizing farm animals to humans is not well established and bioaerosols could play an important role. The aim of this study was to assess the potential occupational risk of working with S. aureus-colonized pigs in Switzerland. We estimated the airborne contamination by S. aureus in 37 pig farms (20 nursery and 17 fattening units; 25 in summer, 12 in winter). Quantification of total airborne bacterial DNA, airborne Staphylococcus sp. DNA, fungi, and airborne endotoxins was also performed. In this experiment, the presence of cultivable airborne methicillin-resistant S. aureus (MRSA) CC398 in a pig farm in Switzerland was reported for the first time. Airborne methicillin-sensitive S. aureus (MSSA) was found in ~30% of farms. The average airborne concentration of DNA copy number of total bacteria and Staphylococcus sp. measured by quantitative polymerase chain reaction was very high, respectively reaching values of 75 (± 28) × 10(7) and 35 (± 9.8) × 10(5) copy numbers m(-3) in summer and 96 (± 19) × 10(8) and 40 (± 12) × 10(6) copy numbers m(-3) in winter. Total mean airborne concentrations of endotoxins (1298 units of endotoxin m(-3)) and fungi (5707 colony-forming units m(-3)) exceeded the Swiss recommended values and were higher in winter than in summer. In conclusion, Swiss pig farmers will have to tackle a new emerging occupational risk, which could also have a strong impact on public health. The need to inform pig farmers about biological occupational risks is therefore crucial.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Plusieurs études ont examiné la sensibilité aux antimicrobiens chez les bactéries d’organismes provenant de produits issus de l’aquaculture ou de leur environnement. Aucune information n’est cependant disponible concernant la résistance aux antimicrobiens dans les bactéries de la flore de poissons ou de fruits de mer vendus au détail au Canada. C’est particulièrement vrai en ce qui a trait aux bactéries des genres Aeromonas et Vibrio, dont certaines espèces sont des agents pathogènes zoonotiques connus. Au cours de cette étude, la sensibilité aux antimicrobiens d’isolats d’Aeromonas spp. et de Vibrio spp. provenant de poissons et de crevettes domestiques et importés a été mesurée à l’aide de techniques de micro dilution en bouillon et/ou de diffusion sur disque. Les classes d’antimicrobiens examinés comprenaient les tétracyclines (TET), les inhibiteurs de la voie des folates (sulfadiméthoxine-triméthoprime, SXT), le florfenicol (FLO), et les quinolones (acide nalidixique / enrofloxacine, NA/ENO). Des valeurs seuils épidémiologiques pour Aeromonas et Vibrio ont été établies en utilisant la méthode d’interprétation normalisée des données de résistance provenant de diffusion sur disque. La recherche de gènes de résistance associés au profil de résistance des isolats a été effectuée en utilisant des PCRs et des puces ADN. Le nombre d’isolats résistants aux divers antimicrobiens parmi les 201 isolats d’Aeromonas et les 185 isolats de Vibrio étaient respectivement les suivants: TET (n=24 et 10), FLO (n=1 et 0), SXT (n=2 et 8), NA (n=7 et 5) et ENO (n= 5 et 0). Diverses associations de gènes tet(A), tet(B), tet(E), floR, sul1, sul2, et intI1 ont été détectées, les gènes tet(E), intI1, sul2 et tet(B) étant les plus communs. Les espèces d’Aeromonas et de Vibrio isolées de poissons au détail et de fruits de mer peuvent héberger une variété de gènes de résistance, bien que peu fréquemment. Le risque que représente ces gènes de résistance reste à évaluer en considérant le potentiel infectieux des bactéries, l’utilisation des ces agents antimicrobiens pour le traitement des maladies en aquaculture et en médecine humaine et leur rôle en tant que réservoir de la résistance antimicrobienne.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Leptospira have a worldwide distribution and include important zoonotic pathogens yet diagnosis and differentiation still tend to rely on traditional bacteriological and serological approaches. In this study a 1.3 kb fragment of the rrs gene (16S rDNA) was sequenced from a panel of 22 control strains, representing serovars within the pathogenic species Leptospira interrogans, Leptospira borgpetersenii, and Leptospira kirschneri, to identify single nucleotide polymorphisms (SNPs). These were identified in the 5' variable region of the 16S sequence and a 181 bp PCR fragment encompassing this region was used for speciation by Denaturing High Performance Liquid Chromatography (D-HPLC). This method was applied to eleven additional species, representing pathogenic, non-pathogenic and intermediate species and was demonstrated to rapidly differentiate all but 2 of the non-pathogenic Leptospira species. The method was applied successfully to infected tissues from field samples proving its value for diagnosing leptospiral infections found in animals in the UK. Crown Copyright (C) 2010 Published by Elsevier Ltd. All rights reserved.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Paracoccidioides brasiliensis infections have been little studied in wild and/or domestic animals, which may represent an important indicator of the presence of the pathogen in nature. Road-killed wild animals have been used for surveillance of vectors of zoonotic pathogens and may offer new opportunities for eco-epidemiological studies of paracoccidiodomycosis (PCM). The presence of P. brasiliensis infection was evaluated by Nested-PCR in tissue samples collected from 19 road-killed animals; 3 Cavia aperea (guinea pig), 5 Cerdocyon thous (crab-eating-fox), 1 Dasypus novemcinctus (nine-banded armadillo), 1 Dasypus septemcinctus (seven-banded armadillo), 2 Didelphis albiventris (white-eared opossum), 1 Eira barbara (tayra), 2 Gallictis vittata (grison), 2 Procyon cancrivorus (raccoon) and 2 Sphiggurus spinosus (porcupine). Specific P. brasiliensis amplicons were detected in (a) several organs of the two armadillos and one guinea pig, (b) the lung and liver of the porcupine, and (c) the lungs of raccoons and grisons. P. brasiliensis infection in wild animals from endemic areas might be more common than initially postulated. Molecular techniques can be used for detecting new hosts and mapping 'hot spot' areas of PCM.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

The use of laboratory animals in conjunction with research on the human organism provides a basis for on understanding of several important physiological and pathological processes. Besides, the results of experimental studies enable technical and safety improvements to be made in surgical techniques used in the medical clinic. As living biological material is involved, we should guarantee its physical well-being, taking into account microbiological contamination and the genetics, nutrition and correct manipulation of the animals, in order to avoid incorrect conclusions from the experiments or unnecessarily large numbers of animals being used. In parallel with the concerns and legislation on the use of laboratory animals, there is also a growing preoccupation with the welfare and safety of those who handle the laboratory animals, since they run the risk of acquiring occupational diseases through contact with zoonotic pathogens or developing allergies. Prevention requires the application of modern technological advances in the design of the animal house and in the work routines. Unfortunately, few establishments in Brazil possess staff with adequate training and a basic infrastructure of research that includes the laboratory animal breeding centers, equivalent to those existing ones in the United States and Europe.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Background: Mycobacterium spp. is one of the most important species of zoonotic pathogens that can be transmitted from cattle to humans. The presence of these opportunistic, pathogenic bacteria in bovine milk has emerged as a public-health concern, especially among individuals who consume raw milk and related dairy products. To address this concern, the Brazilian control and eradication program focusing on bovine tuberculosis, was established in 2001. However, bovine tuberculosis continues to afflict approximately 1,3 percent of the cattle in Brazil. In the present study, 300 samples of milk from bovine herds, obtained from both individual and collective bulk tanks and informal points of sale, were cultured on Löwenstein-Jensen and Stonebrink media. Polymerase chain reaction (PCR)-based tests and restriction-enzyme pattern analysis were then performed on the colonies exhibiting phenotypes suggestive of Mycobacterium spp., which were characterized as acid-fast bacilli.Results: Of the 300 bovine milk samples that were processed, 24 were positively identified as Mycobacterium spp.Molecular identification detected 15 unique mycobacterial species: Mycobacterium bovis, M. gordonae, M. fortuitum, M. intracellulare, M. flavescens, M. duvalii, M. haemophilum, M. immunogenum, M. lentiflavum, M. mucogenicum, M. novocastrense, M. parafortuitum, M. smegmatis, M. terrae and M. vaccae. The isolation of bacteria from the various locations occurred in the following proportions: 9 percent of the individual bulk-tank samples, 7 percent of the collective bulk-tank samples and 8 percent of the informal-trade samples. No statistically significant difference was observed between the presence of Mycobacterium spp. in the three types of samples collected, the milk production profiles, the presence of veterinary assistance and the reported concerns about bovine tuberculosis prevention in the herds.Conclusion: The microbiological cultures associated with PCR-based identification tests are possible tools for the investigation of the presence of Mycobacterium spp. in milk samples. Using these methods, we found that the Brazilian population may be regularly exposed to mycobacteria by consuming raw bovine milk and related dairy products. These evidences reinforces the need to optimize quality programs of dairy products, to intensify the sanitary inspection of these products and the necessity of further studies on the presence of Mycobacterium spp. in milk and milk-based products. © 2013 Franco et al.; licensee BioMed Central Ltd.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Stressful situations reduce the welfare, production indices and immune status of chickens. Salmonella spp. are a major zoonotic pathogens that annually cause over 1 billion infections worldwide. We therefore designed the current experiment to analyse the effects of 31 +/- 1 degrees C heat stress (HS) (from 35 to 41 days) on performance parameters, Salmonella invasion and small intestine integrity in broiler chickens infected with Salmonella Enteritidis. We observed that HS decreased body weight gain and feed intake. However, feed conversion was only increased when HS was combined with Salmonella Enteritidis infection. In addition, we observed an increase in serum corticosterone levels in all of the birds that were subjected to HS, showing a hypothalamus-pituitary-adrenal axis activation. Furthermore, mild acute multifocal lymphoplasmacytic enteritis, characterized by foci of heterophil infiltration in the duodenum, jejunum and ileum, was observed in the HS group. In contrast, similar but more evident enteritis was noted in the heat-stressed and Salmonella-infected group. In this group, moderate enteritis was observed in all parts of the small intestine. Lastly, we observed an increase in Salmonella counts in the spleens of the stressed and Salmonella-infected chickens. The combination of HS and Salmonella Enteritidis infection may therefore disrupt the intestinal barrier, which would allow pathogenic bacteria to migrate through the intestinal mucosa to the spleen and generate an inflammatory infiltrate in the gut, decreasing performance parameters.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Coproscopic examination of 505 dogs originating from the western or central part of Switzerland revealed the presence (prevalence data) of the following helminthes: Toxocara canis (7.1%), hookworms (6.9%), Trichuris vulpis (5.5%), Toxascaris leonina (1.3%), Taeniidae (1.3%), Capillaria spp. (0.8%), and Diphyllobothrium latum (0.4%). Potential risk factors for infection were identified by a questionnaire: dogs from rural areas significantly more often had hookworms and taeniid eggs in their feces when compared to urban family dogs. Access to small rodents, offal, and carrion was identified as risk factor for hookworm and Taeniidae, while feeding of fresh and uncooked meat did not result in higher prevalences for these helminths. A group of 111 dogs was treated every 3 months with a combined medication of pyrantel embonate, praziquantel, and febantel, and fecal samples were collected for coproscopy in monthly intervals. Despite treatment, the yearly incidence of T. canis was 32%, while hookworms, T. vulpis, Capillaria spp., and Taeniidae reached incidences ranging from 11 to 22%. Fifty-seven percent of the 111 dogs had helminth eggs in their feces at least once during the 1-year study period. This finding implicates that an infection risk with potential zoonotic pathogens cannot be ruled out for the dog owner despite regular deworming four times a year.