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[PMID]:28454560
[Au] Autor:Corbett CS; De Buck J; Orsel K; Barkema HW
[Ad] Endereço:Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.
[Ti] Título:Fecal shedding and tissue infections demonstrate transmission of Mycobacterium avium subsp. paratuberculosis in group-housed dairy calves.
[So] Source:Vet Res;48(1):27, 2017 04 28.
[Is] ISSN:1297-9716
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Current Johne's disease control programs primarily focus on decreasing transmission of Mycobacterium avium subsp. paratuberculosis (MAP) from infectious adult cows to susceptible calves. However, potential transmission between calves is largely overlooked. The objective was to determine the extent of MAP infection in calves contact-exposed to infectious penmates. Thirty-two newborn Holstein-Friesian calves were grouped into 7 experimental groups of 4, consisting of 2 inoculated (IN) calves, and 2 contact-exposed (CE) calves, and 1 control pen with 4 non-exposed calves. Calves were group housed for 3 months, with fecal samples were collected 3 times per week, blood and environmental samples weekly, and tissue samples at the end of the trial. The IN calves exited the trial after 3 months of group housing, whereas CE calves were individually housed for an additional 3 months before euthanasia. Control calves were group-housed for the entire trial. All CE and IN calves had MAP-positive fecal samples during the period of group housing; however, fecal shedding had ceased at time of individual housing. All IN calves had MAP-positive tissue samples at necropsy, and 7 (50%) of the CE had positive tissue samples. None of the calves had a humoral immune response, whereas INF-γ responses were detected in all IN calves and 5 (36%) CE calves. In conclusion, new MAP infections occurred due to exposure of infectious penmates to contact calves. Therefore, calf-to-calf transmission is a potential route of uncontrolled transmission on cattle farms.
[Mh] Termos MeSH primário: Derrame de Bactérias
Doenças dos Bovinos/transmissão
Indústria de Laticínios
Fezes/microbiologia
Abrigo para Animais
Paratuberculose/transmissão
[Mh] Termos MeSH secundário: Animais
Bovinos
Doenças dos Bovinos/microbiologia
Feminino
Mycobacterium avium subsp. paratuberculosis
Paratuberculose/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1709
[Cu] Atualização por classe:180307
[Lr] Data última revisão:
180307
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170430
[St] Status:MEDLINE
[do] DOI:10.1186/s13567-017-0431-8


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[PMID]:28797098
[Au] Autor:Katani R; Cote R; Kudva IT; DebRoy C; Arthur TM; Kapur V
[Ad] Endereço:Department of Animal Science, The Pennsylvania State University, University Park, Pennsylvania, United States of America.
[Ti] Título:Comparative genomics of two super-shedder isolates of Escherichia coli O157:H7.
[So] Source:PLoS One;12(8):e0182940, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Shiga toxin-producing Escherichia coli O157:H7 (O157) are zoonotic foodborne pathogens and of major public health concern that cause considerable intestinal and extra-intestinal illnesses in humans. O157 colonize the recto-anal junction (RAJ) of asymptomatic cattle who shed the bacterium into the environment through fecal matter. A small subset of cattle, termed super-shedders (SS), excrete O157 at a rate (≥ 104 CFU/g of feces) that is several orders of magnitude greater than other colonized cattle and play a major role in the prevalence and transmission of O157. To better understand microbial factors contributing to super-shedding we have recently sequenced two SS isolates, SS17 (GenBank accession no. CP008805) and SS52 (GenBank accession no. CP010304) and shown that SS isolates display a distinctive strongly adherent phenotype on bovine rectal squamous epithelial cells. Here we present a detailed comparative genomics analysis of SS17 and SS52 with other previously characterized O157 strains (EC4115, EDL933, Sakai, TW14359). The results highlight specific polymorphisms and genomic features shared amongst SS strains, and reveal several SNPs that are shared amongst SS isolates, including in genes involved in motility, adherence, and metabolism. Finally, our analyses reveal distinctive patterns of distribution of phage-associated genes amongst the two SS and other isolates. Together, the results of our comparative genomics studies suggest that while SS17 and SS52 share genomic features with other lineage I/II isolates, they likely have distinct recent evolutionary histories. Future comparative and functional genomic studies are needed to decipher the precise molecular basis for super shedding in O157.
[Mh] Termos MeSH primário: Derrame de Bactérias
Doenças dos Bovinos/microbiologia
Bovinos/microbiologia
Infecções por Escherichia coli/veterinária
Escherichia coli O157/genética
Escherichia coli O157/fisiologia
[Mh] Termos MeSH secundário: Animais
Infecções por Escherichia coli/microbiologia
Escherichia coli O157/isolamento & purificação
Genoma Bacteriano
Seres Humanos
Polimorfismo de Nucleotídeo Único
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171004
[Lr] Data última revisão:
171004
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170811
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0182940


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[PMID]:28532993
[Au] Autor:Delaude A; Rodriguez-Campos S; Dreyfus A; Counotte MJ; Francey T; Schweighauser A; Lettry S; Schuller S
[Ad] Endereço:Department Clinical VeterinaryMedicine, Vetsuisse Faculty, University of Bern, Switzerland.
[Ti] Título:Canine leptospirosis in Switzerland-A prospective cross-sectional study examining seroprevalence, risk factors and urinary shedding of pathogenic leptospires.
[So] Source:Prev Vet Med;141:48-60, 2017 Jun 01.
[Is] ISSN:1873-1716
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Leptospirosis is an important worldwide zoonosis. While human leptospirosis remains rare in Switzerland, the incidence of canine leptospirosis is unusually high compared to other European countries. The aims of this cross-sectional study were to determine the exposure of asymtomatic dogs to pathogenic Leptospira in Switzerland, to characterise risk factors associated with seropositivity and to determine the prevalence of urinary shedding. Sampling was stratified to cover the whole of Switzerland. Sera were tested by microscopic agglutination test for antibodies against a panel of 12 serovars. Urine was tested for pathogenic Leptospira using a LipL32 real-time PCR. Of 377 sera, 55.7% (95%CI 51.2-60.7) showed a reciprocal MAT titre of ≥1:40 and 24.9% (95%CI 20.7-29.4) of ≥1:100 to at least one serovar. Seropositivity (MAT ≥1:100) was most common to serovars Australis (14.9%; 95% CI 11.4-18.6) and Bratislava (8.8%; 95%CI 6.1-11.7), followed by Copenhageni (6.1%; 95%CI 3.7-8.5), Canicola (5%; 95%CI 2.9-7.4), Grippotyphosa (4.5%; 95%CI 2.7-6.9), Pomona (4%; 95%CI 2.1-6.1), Autumnalis (2.7%; 95%CI 1.3-4.2) and Icterohaemorrhagiae (1.6%; 95%CI 0.5-2.9). In unvaccinated dogs (n=84) the prevalence of a MAT titre ≥100 was 17.9% (95%CI 10.7-26.2), with a similar distribution of reactive serovars. Variables associated with seropositivity (≥1:40) to any serovar included age (OR 1.29/year; 95%CI: 1.1-1.5) and bioregion with higher risks in the regions Northern Alps (OR 14.5; 95%CI 2.2-292.7), Central Plateau (OR 12.3; 95%CI 2.0-244.1) and Jura (OR 11.2; 95%CI 1.7-226.7) compared to Southern Central Alps. Dogs living with horses were significantly more likely to have antibodies to serovar Bratislava (OR 4.68;95%CI 1.2-17.2). Hunting was a significant risk factor for seropositivtiy to serovar Grippotyphosa (OR 8.03; 95%CI 1.6-30.8). Urine qPCR positivity was uncommon (1/408 dogs; 0.2%; 95% CI0-0.7). These results demonstrate that dogs in Switzerland are commonly exposed to pathogenic Leptospira; however, the risk of dogs contributing to the spread of Leptospira in the environment appears low.
[Mh] Termos MeSH primário: Doenças do Cão/epidemiologia
Leptospirose/veterinária
[Mh] Termos MeSH secundário: Animais
Derrame de Bactérias
Estudos Transversais
DNA Bacteriano/urina
Cães
Feminino
Leptospirose/epidemiologia
Leptospirose/urina
Masculino
Prevalência
Estudos Prospectivos
Reação em Cadeia da Polimerase em Tempo Real/veterinária
Estudos Soroepidemiológicos
Especificidade da Espécie
Suíça/epidemiologia
Urina/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170524
[St] Status:MEDLINE


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[PMID]:28516860
[Au] Autor:Bearson BL; Bearson SMD; Brunelle BW; Bayles DO; Lee IS; Kich JD
[Ad] Endereço:1​USDA/ARS/National Laboratory for Agriculture and the Environment, Ames, IA, 50011, USA.
[Ti] Título:Salmonella DIVA vaccine reduces disease, colonization and shedding due to virulent S. Typhimurium infection in swine.
[So] Source:J Med Microbiol;66(5):651-661, 2017 May.
[Is] ISSN:1473-5644
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:PURPOSE: Non-host-adapted Salmonella serovars, including the common human food-borne pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium), are opportunistic pathogens that can colonize food-producing animals without causing overt disease. Interventions against Salmonella are needed to enhance food safety, protect animal health and allow the differentiation of infected from vaccinated animals (DIVA). METHODOLOGY: An attenuated S. Typhimurium DIVA vaccine (BBS 866) was characterized for the protection of pigs following challenge with virulent S. Typhimurium. The porcine transcriptional response to BBS 866 vaccination was evaluated. RNA-Seq analysis was used to compare gene expression between BBS 866 and its parent; phenotypic assays were performed to confirm transcriptional differences observed between the strains. RESULTS: Vaccination significantly reduced fever and interferon-gamma (IFNγ) levels in swine challenged with virulent S. Typhimurium compared to mock-vaccinated pigs. Salmonella faecal shedding and gastrointestinal tissue colonization were significantly lower in vaccinated swine. RNA-Seq analysis comparing BBS 866 to its parental S. Typhimurium strain demonstrated reduced expression of the genes involved in cellular invasion and bacterial motility; decreased invasion of porcine-derived IPEC-J2 cells and swimming motility for the vaccine strain was consistent with the RNA-Seq analysis. Numerous membrane proteins were differentially expressed, which was an anticipated gene expression pattern due to the targeted deletion of several regulatory genes in the vaccine strain. RNA-Seq analysis indicated that genes involved in the porcine immune and inflammatory response were differentially regulated at 2 days post-vaccination compared to pre-vaccination. CONCLUSION: Evaluation of the S. Typhimurium DIVA vaccine indicates that vaccination will provide both swine health and food safety benefits.
[Mh] Termos MeSH primário: Salmonelose Animal/prevenção & controle
Vacinas contra Salmonella/administração & dosagem
Salmonella typhimurium/imunologia
Doenças dos Suínos/prevenção & controle
Vacinas de DNA/administração & dosagem
[Mh] Termos MeSH secundário: Animais
Anticorpos Antibacterianos/sangue
Derrame de Bactérias
Linhagem Celular
Ensaio de Imunoadsorção Enzimática
Fezes/microbiologia
Expressão Gênica
Perfilação da Expressão Gênica
Seres Humanos
Interferon gama/imunologia
Salmonelose Animal/imunologia
Salmonelose Animal/microbiologia
Vacinas contra Salmonella/imunologia
Salmonella typhimurium/metabolismo
Salmonella typhimurium/patogenicidade
Suínos
Doenças dos Suínos/microbiologia
Vacinação
Vacinas Atenuadas/administração & dosagem
Vacinas Atenuadas/imunologia
Vacinas de DNA/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Bacterial); 0 (Salmonella Vaccines); 0 (Vaccines, Attenuated); 0 (Vaccines, DNA); 82115-62-6 (Interferon-gamma)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170614
[Lr] Data última revisão:
170614
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170519
[St] Status:MEDLINE
[do] DOI:10.1099/jmm.0.000482


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[PMID]:28403908
[Au] Autor:Sobotta K; Bonkowski K; Liebler-Tenorio E; Germon P; Rainard P; Hambruch N; Pfarrer C; Jacobsen ID; Menge C
[Ad] Endereço:Institute of Molecular Pathogenesis, Friedrich-Loeffler-Institut (FLI), Naumburger Strasse 96a, 07743, Jena, Germany.
[Ti] Título:Permissiveness of bovine epithelial cells from lung, intestine, placenta and udder for infection with Coxiella burnetii.
[So] Source:Vet Res;48(1):23, 2017 Apr 12.
[Is] ISSN:1297-9716
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Ruminants are the main source of human infections with the obligate intracellular bacterium Coxiella (C.) burnetii. Infected animals shed high numbers of C. burnetii by milk, feces, and birth products. In goats, shedding by the latter route coincides with C. burnetii replication in epithelial (trophoblast) cells of the placenta, which led us to hypothesize that epithelial cells are generally implicated in replication and shedding of C. burnetii. We therefore aimed at analyzing the interactions of C. burnetii with epithelial cells of the bovine host (1) at the entry site (lung epithelium) which govern host immune responses and (2) in epithelial cells of gut, udder and placenta decisive for the quantity of pathogen excretion. Epithelial cell lines [PS (udder), FKD-R 971 (small intestine), BCEC (maternal placenta), F3 (fetal placenta), BEL-26 (lung)] were inoculated with C. burnetii strains Nine Mile I (NMI) and NMII at different cultivation conditions. The cell lines exhibited different permissiveness for C. burnetii. While maintaining cell viability, udder cells allowed the highest replication rates with formation of large cell-filling Coxiella containing vacuoles. Intestinal cells showed an enhanced susceptibility to invasion but supported C. burnetii replication only at intermediate levels. Lung and placental cells also internalized the bacteria but in strikingly smaller numbers. In any of the epithelial cells, both Coxiella strains failed to trigger a substantial IL-1ß, IL-6 and TNF-α response. Epithelial cells, with mammary epithelial cells in particular, may therefore serve as a niche for C. burnetii replication in vivo without alerting the host's immune response.
[Mh] Termos MeSH primário: Doenças dos Bovinos/microbiologia
Coxiella burnetii/fisiologia
Células Epiteliais/microbiologia
Mucosa Intestinal/microbiologia
Pulmão/microbiologia
Glândulas Mamárias Animais/microbiologia
Placenta/microbiologia
Febre Q/veterinária
[Mh] Termos MeSH secundário: Animais
Derrame de Bactérias
Bovinos/microbiologia
Linhagem Celular
Citocinas/fisiologia
Feminino
Citometria de Fluxo/veterinária
Interações Hospedeiro-Patógeno/fisiologia
Microscopia de Fluorescência/veterinária
Gravidez
Febre Q/microbiologia
Reação em Cadeia da Polimerase em Tempo Real/veterinária
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Cytokines)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170928
[Lr] Data última revisão:
170928
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170414
[St] Status:MEDLINE
[do] DOI:10.1186/s13567-017-0430-9


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[PMID]:28364832
[Au] Autor:Lynch H; Leonard FC; Walia K; Lawlor PG; Duffy G; Fanning S; Markey BK; Brady C; Gardiner GE; Argüello H
[Ad] Endereço:National Food Research Centre, Teagasc, Ashtown, Dublin, Ireland; UCD Veterinary Sciences Centre, University College Dublin, Dublin, Ireland. Electronic address: Lynchhelen28@gmail.com.
[Ti] Título:Investigation of in-feed organic acids as a low cost strategy to combat Salmonella in grower pigs.
[So] Source:Prev Vet Med;139(Pt A):50-57, 2017 Apr 01.
[Is] ISSN:1873-1716
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Salmonella carriage in pigs is a significant food safety issue. Dietary supplementation with organic acids has previously been shown to reduce shedding and transmission of Salmonella. Therefore, this study aimed to examine the effect of three commercially available organic acid-based products on Salmonella levels in grower pigs, using a model of experimental infection that closely mimics natural exposure to the organism. Seven week old trial pigs (n=40) with a mean weight of 14.7kg were placed in one of four pens with 10 pigs/pen. Pens had previously been contaminated with Salmonella Typhimurium 4,[5],12;i;- via seeder pigs. Trial pigs received one of four diets for 28days: 1, control diet; 2, sodium butyrate supplemented diet; 3, benzoic acid supplemented diet and 4, formic-citric acid supplemented diet. A further 10 pigs were placed in a Salmonella-free pen receiving the control diet. Pigs were weighed and blood sampled on days 0 and 28. Faeces was collected on day 0, 2, 3, 5, 7, 14, 21 and 28 and examined for Salmonella. On day 28, 5 pigs/group were euthanised and ileocaecal lymph nodes (ILN) and caecal contents sampled for culture. The remaining 5 pigs/pen were then fed the control diet and faeces were collected on days 35 and 42. On day 42 pigs were euthanised and ILN and caecal contents tested for Salmonella levels. The trial was repeated once. Within the first two days of exposure to the contaminated environment, 96% (77/80) of pigs became infected. Most pigs shed Salmonella at levels of between 10 -10 CFU/g faeces for at least 7days post-exposure. A significant reduction in Salmonella faecal concentration was observed after supplementation with sodium butyrate (p=0.001) and a formic citric acid blend (p<0.0001). Average daily weight gain (ADWG) was significantly increased in all groups fed the supplemented feed when compared to the positive control group. The use of sodium butyrate or a blend of formic and citric acid in feed could be considered a cost-effective control measure to reduce Salmonella faecal shedding and improve ADWG in Salmonella infected herds.
[Mh] Termos MeSH primário: Ração Animal
Ácido Butírico/administração & dosagem
Ácido Cítrico/administração & dosagem
Formiatos/administração & dosagem
Salmonelose Animal/prevenção & controle
Doenças dos Suínos/prevenção & controle
[Mh] Termos MeSH secundário: Análise de Variância
Animais
Derrame de Bactérias/efeitos dos fármacos
Ácido Benzoico/administração & dosagem
Ceco/microbiologia
Suplementos Nutricionais
Eutanásia Animal
Fezes/microbiologia
Distribuição Aleatória
Salmonelose Animal/sangue
Salmonella typhimurium/isolamento & purificação
Suínos
Doenças dos Suínos/sangue
Doenças dos Suínos/microbiologia
Ganho de Peso
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Formates); 0YIW783RG1 (formic acid); 107-92-6 (Butyric Acid); 2968PHW8QP (Citric Acid); 8SKN0B0MIM (Benzoic Acid)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170821
[Lr] Data última revisão:
170821
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170403
[St] Status:MEDLINE


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[PMID]:28333229
[Au] Autor:Stein RA; Katz DE
[Ad] Endereço:Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA.
[Ti] Título:Escherichia coli, cattle and the propagation of disease.
[So] Source:FEMS Microbiol Lett;364(6), 2017 Mar 01.
[Is] ISSN:1574-6968
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Several early models describing host-pathogen interaction have assumed that each individual host has approximately the same likelihood of becoming infected or of infecting others. More recently, a concept that has been increasingly emphasized in many studies is that for many infectious diseases, transmission is not homogeneous but highly skewed at the level of populations. In what became known as the '20/80 rule', about 20% of the hosts in a population were found to contribute to about 80% of the transmission potential. These heterogeneities have been described for the interaction between many microorganisms and their human or animal hosts. Several epidemiological studies have reported transmission heterogeneities for Escherichia coli by cattle, a phenomenon with far-reaching agricultural, medical and public health implications. Focusing on E. coli as a case study, this paper will describe super-spreading and super-shedding by cattle, review the main factors that shape these transmission heterogeneities and examine the interface with human health. Escherichia coli super-shedding and super-spreading by cattle are shaped by microorganism-specific, cattle-specific and environmental factors. Understanding the factors that shape heterogeneities in E. coli dispersion by cattle and the implications for human health represent key components that are critical for targeted infection control initiatives.
[Mh] Termos MeSH primário: Doenças dos Bovinos/microbiologia
Infecções por Escherichia coli/veterinária
Escherichia coli/fisiologia
[Mh] Termos MeSH secundário: Animais
Derrame de Bactérias
Bovinos
Doenças dos Bovinos/epidemiologia
Doenças dos Bovinos/transmissão
Meio Ambiente
Interações Hospedeiro-Patógeno
Virulência
Fatores de Virulência
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Virulence Factors)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170629
[Lr] Data última revisão:
170629
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170324
[St] Status:MEDLINE
[do] DOI:10.1093/femsle/fnx050


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[PMID]:28292980
[Au] Autor:Zangari T; Wang Y; Weiser JN
[Ad] Endereço:Department of Microbiology, New York University School of Medicine, New York, New York, USA.
[Ti] Título: Transmission Is Blocked by Type-Specific Immunity in an Infant Mouse Model.
[So] Source:MBio;8(2), 2017 Mar 14.
[Is] ISSN:2150-7511
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Epidemiological studies on show that rates of carriage are highest in early childhood and that the major benefit of the pneumococcal conjugate vaccine (PCV) is a reduction in the incidence of nasopharyngeal colonization through decreased transmission within a population. In this study, we sought to understand how anti- immunity affects nasal shedding of bacteria, the limiting step in experimental pneumococcal transmission. Using an infant mouse model, we examined the role of immunity (passed from mother to pup) on shedding and within-litter transmission of by pups infected at 4 days of life. Pups from both previously colonized immune and PCV-vaccinated mothers had higher levels of anti- IgG than pups from non-immune or non-vaccinated mothers and shed significantly fewer over the first 5 days of infection. By setting up cross-foster experiments, we demonstrated that maternal passage of antibody to pups either or post-natally decreases shedding. Passive immunization experiments showed that type-specific antibody to capsular polysaccharide is sufficient to decrease shedding and that the agglutinating function of immunoglobulin is required for this effect. Finally, we established that anti-pneumococcal immunity and anti-PCV vaccination block host-to-host transmission of Moreover, immunity in either the donor or recipient pups alone was sufficient to reduce rates of transmission, indicating that decreased shedding and protection from acquisition of colonization are both contributing factors. Our findings provide a mechanistic explanation for the reduced levels of transmission between hosts immune from prior exposure and among vaccinated children. Rates of carriage of the bacterial pathogen are highest among young children, and this is the target group for the pneumococcal conjugate vaccine (PCV). Epidemiological studies have suggested that a major benefit of the PCV is a reduction in host-to-host transmission, which also protects the non-vaccinated population ("herd immunity"). In this study, we examined the role of anti-pneumococcal immunity on nasal shedding and transmission of the pathogen using an infant mouse model. We found that shedding is decreased and transmission is blocked by anti-pneumococcal immunity and PCV vaccination. Additionally, transmission rates decreased if either the infected or contact pups were immune, indicating that reduced shedding and protection from the establishment of colonization are both contributing factors. Our study provides a mechanistic explanation for the herd immunity effect seen after the introduction of PCV and identifies potential points of intervention, which may have implications for future vaccine development.
[Mh] Termos MeSH primário: Derrame de Bactérias
Transmissão de Doença Infecciosa/prevenção & controle
Infecções Pneumocócicas/transmissão
Streptococcus pneumoniae/imunologia
[Mh] Termos MeSH secundário: Animais
Animais Recém-Nascidos
Anticorpos Antibacterianos/sangue
Modelos Animais de Doenças
Imunidade Materno-Adquirida
Imunização Passiva
Camundongos
Streptococcus pneumoniae/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antibodies, Bacterial)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170626
[Lr] Data última revisão:
170626
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170316
[St] Status:MEDLINE


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[PMID]:28260536
[Au] Autor:Lee K; Kusumoto M; Iwata T; Iyoda S; Akiba M
[Ad] Endereço:Division of Bacterial and Parasitic Disease Research,National Institute of Animal Health, National Agriculture and Food Research Organization,Tsukuba,Ibaraki,Japan.
[Ti] Título:Nationwide investigation of Shiga toxin-producing Escherichia coli among cattle in Japan revealed the risk factors and potentially virulent subgroups.
[So] Source:Epidemiol Infect;145(8):1557-1566, 2017 06.
[Is] ISSN:1469-4409
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A nationwide study of Shiga toxin-producing Escherichia coli (STEC) was performed to determine the prevalence, characteristics and risk factors for fecal shedding of STEC among cattle in Japan. Information on rearing practices was also collected to identify risk factors for fecal shedding of STEC. STEC was isolated from 24·1% of samples (133/551) collected from 59·1% of farms (65/110). Bayesian clustering using the virulence marker profiles of the isolates subdivided the isolates into four genetically distinct groups, two of which corresponded to eae- or saa-positive STEC, which can cause severe disease in human. Both STEC groups exhibited characteristic phylogeny and virulence marker profiles. It is noteworthy that the tellurite resistance gene was not detected in all saa-positive STEC isolates, suggesting that the standard isolation method using tellurite might lead to an underestimation of the prevalence of saa-positive STEC. A multivariate logistic regression model using epidemiological information revealed a significantly (P < 0·01) high odds ratio on STEC fecal shedding in tie-stall housing and a low odds ratio in flat feed box and mechanical ventilation. Information on isolate characteristics of the two major pathotypes and risk factors in rearing practices will facilitate the development of preventative measures for STEC fecal shedding from cattle.
[Mh] Termos MeSH primário: Doenças dos Bovinos/epidemiologia
Doenças dos Bovinos/microbiologia
Infecções por Escherichia coli/veterinária
Escherichia coli Shiga Toxigênica/fisiologia
Escherichia coli Shiga Toxigênica/patogenicidade
Fatores de Virulência/isolamento & purificação
[Mh] Termos MeSH secundário: Criação de Animais Domésticos/normas
Animais
Derrame de Bactérias
Teorema de Bayes
Bovinos
Infecções por Escherichia coli/epidemiologia
Infecções por Escherichia coli/microbiologia
Fezes/microbiologia
Feminino
Japão/epidemiologia
Masculino
Filogenia
Prevalência
Fatores de Risco
Escherichia coli Shiga Toxigênica/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Virulence Factors)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:171125
[Lr] Data última revisão:
171125
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170307
[St] Status:MEDLINE
[do] DOI:10.1017/S0950268817000474


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[PMID]:28241895
[Au] Autor:Collins A; Fallon UB; Cosgrove M; Meagher G; Ni Shuileabhan C
[Ad] Endereço:Department of Public Health,HSE-DML,Tullamore,Ireland.
[Ti] Título:A 10-year analysis of VTEC microbiological clearance times, in the under-six population of the Midlands, Ireland.
[So] Source:Epidemiol Infect;145(8):1577-1583, 2017 06.
[Is] ISSN:1469-4409
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Verotoxin-producing Escherichia coli (VTEC) is a significant problem in the under-six population in the Midlands, Ireland. VTEC spreads by person-to-person transmission and children attending childcare facilities are excluded until they achieve two consecutive negative stool samples. This report analyses 10 years data on the number of days children under the age of six take to microbiologically clear VTEC. We identified from our data that the median clearance time for VTEC was 39 days, interquartile range (IQR) 27-56 days, maximum clearance time 283 days. At 70 days from onset of infection, 90% of children had cleared the infection. These findings were slightly more prolonged but consistent with international literature on VTEC clearance times for children. Asymptomatic children cleared VTEC infection significantly faster (median time 25 days IQR 13-43 days) than symptomatic children (median time 43 days IQR 31-58 days). Symptomatic children older than 1 year of age cleared VTEC infection significantly faster (median time 42 days IQR 31-57) than symptomatic children year under 1 year (median time 56 days IQR 35-74 days). This report identifies clear data which can be used to more accurately advise parents on time periods required to achieve microbiological clearance from VTEC.
[Mh] Termos MeSH primário: Derrame de Bactérias
Infecções por Escherichia coli/microbiologia
Escherichia coli Shiga Toxigênica/fisiologia
[Mh] Termos MeSH secundário: Pré-Escolar
Feminino
Seres Humanos
Lactente
Recém-Nascido
Irlanda
Masculino
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1706
[Cu] Atualização por classe:171125
[Lr] Data última revisão:
171125
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170301
[St] Status:MEDLINE
[do] DOI:10.1017/S0950268817000425



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