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1.
Mikrobiyol Bul ; 54(1): 144-153, 2020 Jan.
Artigo em Turco | MEDLINE | ID: mdl-32050885

RESUMO

Avian chlamydiosis, is a highly contagious, systemic disease occuring in domestic and wild birds. Chlamydia psittaci, the causative agent of the disease, is a gram-negative bacterium in the Chlamydiaceae family that can only live within the cell. The agent can be transmitted directly to humans by contact with infected animals or feces of infected animals. It can also be transmitted by inhalation of fecal dust. Since the disease has a zoonotic character, it is also important in terms of public health. By using the monoclonal antibodies against cell wall proteins (OMP) of C.psittaci, six (A-F) and two (WC and M56) serotypes were determined in mammals. The aim of this study was to investigate and genotype the presence of C.psittaci ompA gene in domestic pigeon feces grown in family management style in ten different districts in Ankara in winter and summer seasons. Within the scope of the study, 100 pigeon stool samples were collected from birdhouses in 10 different districts of Ankara (Beypazari, Haymana, Kizilcahamam, Cubuk, Pursaklar, Bala, Cankaya, Polatli, Golbasi and city center) in two different seasons. DNA extraction from fecal samples was performed by classical methods. The presence of the agent in the extracted DNA samples was investigated by polymerase chain reaction (PCR) analysis of the ompA gene. Two-way sequence analysis of the ompA gene was performed with the primers used in the study from the target DNA products amplified by PCR. The results of sequence analysis were compared with the international database and serotyping/genotyping was performed. In the study, C.psittaci ompA gene was detected in 6 (6%) samples of 100 pigeon stool samples. Among these positive samples, two were from Bala (one sample from winter, one sample from summer), two were from Haymana (one sample from winter, one sample from summer) and two were from Golbasi (one sample from winter, one sample from summer); where the same agent was isolated in the same aviaries in different seasons. In this study, no difference was found between the presence of C.psittaci in pigeon droppings and season. In addition when the sequence analysis of the isolated samples were compared with the World database; all isolates were found to be 100% genotype B and 99% genotype E. In this study, the sequence analysis of the ompA gene of C.psittaci from domestic pigeon feces was determined for the first time in Turkey. Although the presence of C.psittaci in domestic pigeons is low, it is a zoonotic bacterium and is important for the public health.


Assuntos
Proteínas da Membrana Bacteriana Externa , Doenças das Aves , Chlamydophila psittaci , Columbidae , Fezes , Psitacose , Animais , Proteínas da Membrana Bacteriana Externa/genética , Doenças das Aves/microbiologia , Chlamydophila psittaci/genética , Columbidae/microbiologia , Fezes/microbiologia , Genótipo , Psitacose/microbiologia , Turquia
2.
J Avian Med Surg ; 33(1): 22-28, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31124608

RESUMO

We determined the prevalence of Chlamydia psittaci genotypes in asymptomatic and symptomatic birds in northeast Iran. Samples were collected from 11 species of Psittaciformes and 1 species of Columbiformes from 2015 to 2016. Choanal cleft and cloacal swab samples, fresh fecal samples, and/or tissue samples of 70 symptomatic and 130 asymptomatic birds were collected and tested by molecular detection (nested polymerase chain reaction [PCR] testing specific for C psittaci). Results showed C psittaci was detected in 37 (18.5%) of 200 birds (18/37 symptomatic and 19/37 asymptomatic birds) by nested PCR assay. Of the PCR-positive samples, 14 products were positive for oligonucleotide sets CTU/CTL by a second PCR assay and genotyped by outer membrane protein A (ompA) gene sequencing. Of the 10 samples positive for genotype A (cockatiels [Nymphicus hollandicus, n = 5], ring-necked parakeet [Psittacula krameri, n = 2], African gray parrot [Psittacus erithacus, n = 3]), 6 samples were from asymptomatic and 4 from symptomatic birds. Genotype B was observed in 3 samples from symptomatic birds (P krameri [n = 2], pigeon [Columba livia, n = 1]), and provisional genotype I was detected in one symptomatic cockatiel. These findings revealed the importance of monitoring imported asymptomatic birds in developing countries, especially the Middle East, where there is no systematic monitoring. To the best of our knowledge, this is the first report regarding the detection of C psittaci provisional genotype I in cockatiels.


Assuntos
Doenças das Aves/microbiologia , Chlamydophila psittaci/classificação , Columbiformes , Genótipo , Psittaciformes , Psitacose/veterinária , Animais , Proteínas da Membrana Bacteriana Externa/genética , Sequência de Bases , Doenças das Aves/epidemiologia , Aves , Chlamydophila psittaci/genética , Columbiformes/microbiologia , Irã (Geográfico)/epidemiologia , Filogenia , Reação em Cadeia da Polimerase/veterinária , Psittaciformes/microbiologia , Psitacose/epidemiologia , Psitacose/microbiologia
3.
Rev Argent Microbiol ; 51(2): 130-135, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30017323

RESUMO

In order to determine the presence and genetic diversity of Chlamydia spp. in the north-eastern area of Buenos Aires province, Argentina, conjunctival, oropharyngeal, cloacal swab and tissues were collected from a total of 90 psittacine pet birds of different age and clinical manifestations. Through molecular methods, Chlamydiaceae was detected in 30% (27/90) of the samples, out of which 70.3% (19/27) were positive for Chlamydia psittaci and 14.9% (4/27) for Chlamydia abortus. Nine C. psittaci positive samples were genotyped by ompA gene sequences, 8 clustered within genotype A and 1 within genotype B. A significant association was observed between the presence of Chlamydia spp. and the manifestation of clinical signs compatible with chlamydiosis, as well as with the age of the birds (younger than one year old). This report contributes to the improvement of our understanding of chlamydial agents in our country.


Assuntos
Doenças das Aves/microbiologia , Infecções por Chlamydia/veterinária , Chlamydia/genética , Chlamydia/isolamento & purificação , Chlamydophila psittaci/genética , Chlamydophila psittaci/isolamento & purificação , Animais de Estimação/microbiologia , Psittaciformes/microbiologia , Psitacose/veterinária , Animais , Argentina , Infecções por Chlamydia/microbiologia , Genótipo , Psitacose/microbiologia
4.
Rev Mal Respir ; 36(3): 298-306, 2019 Mar.
Artigo em Francês | MEDLINE | ID: mdl-30473450

RESUMO

INTRODUCTION: The aim of our study was to compare the features at diagnosis in patients with ornithosis to patients with avian acute hypersensitivity pneumonitis (HP). Clinical, biological and radiological differences could potentially help clinicians to distinguish these diseases. METHODS: We conducted a retrospective study on patients admitted from 2000 to 2016 in three hospitals. Ornithosis was diagnosed based on a positive polymerase chain reaction for Chlamydophila psittaci on respiratory samples and/or a seroconversion while HP was diagnosed on the basis of at least one positive serum precipitin. RESULTS: Twelve patients with HP and 13 patients with ornithosis were identified. Compared to HP, ornithosis occurred more frequently in males (P=0.047), with less previous respiratory diseases (P=0.01), shorter symptom duration (P=0.03), less frequently bilateral crackles (P=0.004), more severe disease requiring more frequently intensive care admission (P=0.005), higher CRP values (P=0.005) and more profound lymphopenia (P=0.02). Ground glass shadowing on CT scan (P=0.001) or bronchiectasis (P=0.03) were more frequently noted in patients with HP. CONCLUSIONS: Our results suggest that patients with ornithosis and HP have important differences in their clinical, biological, and radiological presentation.


Assuntos
Alveolite Alérgica Extrínseca/diagnóstico , Psitacose/diagnóstico , Doença Aguda , Adulto , Idoso , Alveolite Alérgica Extrínseca/epidemiologia , Animais , Aves , Chlamydophila psittaci/genética , Chlamydophila psittaci/isolamento & purificação , Diagnóstico Diferencial , Feminino , Humanos , Testes Imunológicos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Psitacose/epidemiologia , Estudos Retrospectivos , Testes Sorológicos
5.
J Infect Chemother ; 25(1): 41-44, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30377069

RESUMO

The present retrospective study provides an in-depth analysis of the maternal sepsis-related deaths reported in Japan, and aims to guide future care regarding maternal sepsis. This is a nationwide, retrospective, descriptive cohort study. Data were retrospectively analyzed on all maternal death cases related to sepsis reported in Japan from 2010 through 2016. A total of 7,347,727 births and 317 maternal deaths were reported during the study period. The cause of maternal death was sepsis in 24 women (7.5%). Causative bacteria were Streptococcus pyogenes (54.2%), Chlamydia psittaci (8.3%), Mycobacterium tuberculosis (8.3%), Escherichia coli (4.2%), Neisseria meningitidis (4.2%), Epstein-Barr virus (4.2%), and unknown (16.6%). In maternal death due to S. pyogenes (13 women), onset periods ware antepartum in 10 women (76.9%) and postpartum in 3 (23.1%); death within 24 h after hospital admission occurred in 7 women (53.8%); and the median time from hospital admission to death was 12 h (6-744 h). The most common causative bacteria in to maternal sepsis-related death were GAS. When encountering severe sepsis during the peripartum period, we recommend considering severe GAS infection and early intervention.


Assuntos
Mortalidade Materna , Complicações Infecciosas na Gravidez/microbiologia , Complicações Infecciosas na Gravidez/mortalidade , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/mortalidade , Streptococcus pyogenes/isolamento & purificação , Adulto , Chlamydophila psittaci/genética , Chlamydophila psittaci/isolamento & purificação , Estudos de Coortes , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Feminino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Neisseria meningitidis/genética , Neisseria meningitidis/isolamento & purificação , Período Pós-Parto , Gravidez , Complicações Infecciosas na Gravidez/sangue , Estudos Retrospectivos , Infecções Estreptocócicas/sangue , Infecções Estreptocócicas/complicações , Streptococcus pyogenes/genética , Inquéritos e Questionários , Adulto Jovem
6.
BMC Infect Dis ; 18(1): 442, 2018 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30165831

RESUMO

BACKGROUND: Psittacosis outbreak investigations require rapid identification of cases in order to trace possible sources and perform public health risk assessments. In recent outbreaks in the Netherlands, such investigations were hampered by the non-specificity of laboratory testing methods to identify human Chlamydia psittaci infections. METHOD: A systematic search of PubMed and Scopus databases of literature published between 01 January, 1986 and 03 July, 2017 was done to find best practices of laboratory-testing methods used in psittacosis outbreaks of two or more human cases. Reference lists of included articles were hand searched to identify additional articles. RESULTS: Thirty-seven eligible articles were identified, describing 44 human psittacosis outbreaks in 12 countries. Laboratory tests performed were PCR (with various targets), serologic tests (complement binding reactions, ELISA's, immunofluorescence tests and immuno-peroxidase tests) and culture, in various combinations. The literature provided no 'gold standard' laboratory testing strategy to identify recent human C. psittaci infections. In most psittacosis outbreaks, for a considerable number of cases (or tested individuals in an exposed cohort), C. psittaci infection could not be confirmed, nor excluded as causative pathogen. None of the testing strategies was found to be suitable for (nearly) full case finding. CONCLUSION: PCR enables rapid identification of human psittacosis patients and helps source finding by genotyping but has the disadvantage that sensitivity is high only in the acute phase. In outbreak situations, there is often a time delay and therefore, there is a need for new serologic testing methods next to PCR, with good specificity and sensitivity. Moreover, serum is easier to collect than the preferred diagnostic materials for PCR. A serologic test that can reliably confirm infection status without the necessity of convalescent serum sampling would enhance case finding, source tracing, identification of risk factors and assessment of burden of disease in various settings.


Assuntos
Chlamydophila psittaci/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Psitacose/diagnóstico , Animais , Aves , Chlamydophila psittaci/genética , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Bases de Dados Factuais , Surtos de Doenças , Humanos , Reação em Cadeia da Polimerase , Psitacose/epidemiologia , Psitacose/transmissão
7.
BMC Genomics ; 19(1): 575, 2018 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-30068313

RESUMO

BACKGROUND: Members of the phylum Chlamydiae are obligate intracellular pathogens of humans and animals and have a serious impact on host health. They comprise several zoonotic species with varying disease outcomes and prevalence. To investigate differences in virulence, we focused on Chlamydia psittaci, C. abortus and Waddlia chondrophila. Most threatening is C. psittaci, which frequently infects humans and causes psittacosis associated with severe pneumonia. The closest relative of C. psittaci is C. abortus, which shares the vast majority of genes but less frequently infects humans, and causes stillbirth and sepsis. W. chondrophila is more distantly related, and occasional human infections are associated with respiratory diseases or miscarriage. One possible explanation for differences in virulence originate from species-specific genes as well as differentially expressed homologous virulence factors. RESULTS: RNA-sequencing (RNA-Seq) was applied to purified infectious elementary bodies (EBs) and non-infectious reticulate bodies (RBs) in order to elucidate the transcriptome of the infectious and replicative chlamydial states. The results showed that approximately half of all genes were differentially expressed. For a descriptive comparison, genes were categorised according to their function in the RAST database. This list was extended by the inclusion of inclusion membrane proteins, outer membrane proteins, polymorphic membrane proteins and type III secretion system effectors. In addition, the expression of fifty-six known and a variety of predicted virulence and immunogenic factors with homologs in C. psittaci, C. abortus and W. chondrophila was analysed. To confirm the RNA-Seq results, the expression of nine factors was validated using real-time quantitative polymerase chain reaction (RT-qPCR). Comparison of RNA-Seq and RT-qPCR results showed a high mean Pearson correlation coefficient of 0.95. CONCLUSIONS: It was shown that both the replicative and infectious chlamydial state contained distinctive transcriptomes and the cellular processes emphasised in EBs and RBs differed substantially based on the chlamydial species. In addition, the very first interspecies transcriptome comparison is presented here, and the considerable differences in expression of homologous virulence factors might contribute to the differing infection rates and disease outcomes of the pathogens. The RNA-Seq results were confirmed by RT-qPCR and demonstrate the feasibility of interspecies transcriptome comparisons in chlamydia.


Assuntos
Proteínas de Bactérias/genética , Chlamydiales/genética , Perfilação da Expressão Gênica/métodos , Análise de Sequência de RNA/métodos , Animais , Infecções por Chlamydiaceae/microbiologia , Chlamydiales/patogenicidade , Chlamydophila psittaci/genética , Chlamydophila psittaci/patogenicidade , Regulação Bacteriana da Expressão Gênica , Tamanho do Genoma , Genoma Bacteriano , Humanos , Fatores de Virulência/genética
8.
Ann Agric Environ Med ; 25(2): 320-325, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29936804

RESUMO

INTRODUCTION: Chlamydia psittaci is an obligate intracellular Gram-negative bacterium causing respiratory disease (chlamydiosis) or asymptomatic carriage in poultry. In humans, it is a zoonotic agent of ornithosis/psittacosis. Due to low awareness of the disease and variable clinical presentation, psittacosis is often remains unrecognised as such by general practitioners. Zoonotic transfer occurs through inhalation of contaminated aerosols, and originates from feathers, faecal material and respiratory tract exudates. OBJECTIVE: The aim of this study was to investigate chickens for the presence of Chlamydia sp. from pharyngeal and cloacal swabs and review the zoonotic risk for humans. MATERIAL AND METHODS: 138 clinically healthy chickens from farms in Slovakia were examined for the presence of Chlamydia sp. The age of the chickens was 6 months. Two different samples were used - pharyngeal swabs and cloacal swabs. Each sample was examined by the molecular PCR method, and in the case of a positive result the identity of the obtained sequences was examined by a BLAST search. RESULTS: Of the total number of 276 examined samples from 138 chickens, 19 (6.9%) showed positivity for C. psittaci infection, 12 (8.7%) which were positive from pharyngeal swabs and 7 (5.1%) from cloacal swabs. None of the chickens were positive in both samples. Phylogenetic examination of the 19 isolates identified in the study, based on the 23S rRNA gene sequence, revealed that the isolates obtained were identical with C. psittaci, and genetically very close to genotypes B and genotype E. CONCLUSIONS: C. psittaci infections are apparently emerging in chickens. Chicken-processing plant employees should be considered a risk group for human psittacosis. There is a need for higher awareness and for efficient risk assessment and management.


Assuntos
Chlamydophila psittaci/isolamento & purificação , Doenças das Aves Domésticas/microbiologia , Psitacose/microbiologia , Psitacose/veterinária , Zoonoses/microbiologia , Animais , Galinhas/microbiologia , Chlamydophila psittaci/classificação , Chlamydophila psittaci/genética , Genótipo , Humanos , Filogenia , Psitacose/transmissão , Eslováquia , Zoonoses/transmissão
9.
Emerg Microbes Infect ; 7(1): 88, 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29765033

RESUMO

Chlamydia psittaci is an avian pathogen capable of spill-over infections to humans. A parrot C. psittaci strain was recently detected in an equine reproductive loss case associated with a subsequent cluster of human C. psittaci infections. In this study, we screened for C. psittaci in cases of equine reproductive loss reported in regional New South Wales, Australia during the 2016 foaling season. C. psittaci specific-PCR screening of foetal and placental tissue samples from cases of equine abortion (n = 161) and foals with compromised health status (n = 38) revealed C. psittaci positivity of 21.1% and 23.7%, respectively. There was a statistically significant geographical clustering of cases ~170 km inland from the mid-coast of NSW (P < 0.001). Genomic analysis and molecular typing of C. psittaci positive samples from this study and the previous Australian equine index case revealed that the equine strains from different studs in regional NSW were clonal, while the phylogenetic analysis revealed that the C. psittaci strains from both Australian equine disease clusters belong to the parrot-associated 6BC clade, again indicative of spill-over of C. psittaci infections from native Australian parrots. The results of this work suggest that C. psittaci may be a more significant agent of equine reproductive loss than thought. A range of studies are now required to evaluate (a) the exact role that C. psittaci plays in equine reproductive loss; (b) the range of potential avian reservoirs and factors influencing infection spill-over; and


Assuntos
Feto Abortado/microbiologia , Chlamydophila psittaci/isolamento & purificação , Doenças dos Cavalos/microbiologia , Placenta/microbiologia , Complicações Infecciosas na Gravidez/veterinária , Psitacose/veterinária , Animais , Austrália , Chlamydophila psittaci/classificação , Chlamydophila psittaci/genética , DNA Bacteriano/genética , Feminino , Genoma Bacteriano/genética , Cavalos , Tipagem Molecular , Papagaios , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Psitacose/microbiologia
10.
N Z Vet J ; 66(3): 162-165, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29447087

RESUMO

AIM: To describe the Chlamydia psittaci genotypes in samples from native and introduced birds from New Zealand by analysis of the sequence variation of the ompA gene. METHODS: DNA was extracted from samples collected from a non-random sample of birds; either swabs from live asymptomatic birds or birds with clinical signs, or formalin-fixed, paraffin-embedded (FFPE) samples from historical post-mortem cases. The presence of C. psittaci in all samples had been confirmed using a quantitative PCR assay. The C. psittaci ompA gene was amplified and sequenced from samples from 26 native and introduced infected birds comprising 12 different species. These sequences were compared to published available C. psittaci genotypes. RESULTS: Genotypes A and C of C. psittaci were identified in the samples. Genotype A was identified in samples from nine birds, including various native and introduced species. Genotype C was identified in samples from 16 different waterfowl species, and a mixed infection of both genotypes was found in a kaka (Nestor meridionalis). In native birds, C. psittaci infection was confirmed in seven new host species. CONCLUSIONS AND CLINICAL RELEVANCE: Two genotypes (A and C) of C. psittaci were found in samples from a wider range of both native and introduced species of birds in New Zealand than previously reported. Both genotypes have been globally associated with significant disease in birds and humans. These initial results suggest the host range of C. psittaci in New Zealand birds is under-reported. However, the prevalence of C. psittaci infection in New Zealand, and the associated impact on avian and public health, remains to be determined. There are biosecurity implications associated with the importation of birds to New Zealand if there is a limited diversity of C. psittaci genotypes present.


Assuntos
Doenças das Aves/microbiologia , Aves/classificação , Chlamydophila psittaci/genética , Animais , Genótipo , Nova Zelândia , Especificidade da Espécie , Inquéritos e Questionários
12.
Transbound Emerg Dis ; 65(3): 911-915, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29352509

RESUMO

Chlamydia psittaci is an important avian pathogen with spillover from infected wild and domesticated birds also posing a risk to human health. We recently reported a case of C. psittaci equine placentitis associated with further spillover to humans. Molecular typing of this case revealed it belonged to the 6BC clade of C. psittaci, a globally distributed highly virulent set of strains, typically linked to infection spillover from parrots. Equine chlamydiosis associated with C. psittaci infection has previously been reported elsewhere in countries where parrots are not endemic, however, raising questions over the identity of infecting C. psittaci strains and the potential infection reservoirs. In this study, we describe the detection and molecular characterization of C. psittaci in a case of equine abortion in southern Queensland. Equine placenta and fresh liver and lung tissue from the necropsied foetus were positive by C. psittaci-specific qPCR. Chlamydia psittaci-specific multilocus sequence typing and ompA genotyping were used to further characterize the detected equine strains and an additional strain obtained from a dove from a different geographic region presenting with psittacosis. Molecular typing of this case revealed that the infecting equine strains were closely related to the C0sittaci detected in dove, all belonging to an evolutionary lineage of C. psittaci strains typically associated with infections of pigeons globally. This finding suggests a broader diversity of C. psittaci strains may be detected in horses and in association with reproductive loss, highlighting the need for an expansion of surveillance studies globally to understand the epidemiology of equine chlamydiosis and the associated zoonotic risk.


Assuntos
Aborto Animal/microbiologia , Chlamydophila psittaci/isolamento & purificação , Chlamydophila psittaci/patogenicidade , Columbidae/microbiologia , Doenças dos Cavalos/microbiologia , Psitacose/veterinária , Animais , Chlamydophila psittaci/genética , Feminino , Cavalos , Fígado/microbiologia , Pulmão/microbiologia , Tipagem de Sequências Multilocus/veterinária , Placenta/microbiologia , Gravidez , Psitacose/microbiologia , Queensland
13.
Diagn Microbiol Infect Dis ; 90(3): 163-166, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29258707

RESUMO

We describe unanticipated detection of respiratory infection with Chlamydia trachomatis and Chlamydia psittaci after introduction of respiratory multiplex polymerase chain reaction assay that includes Chlamydiaceae family primers. We detected cases of pediatric C. trachomatis and of adult C. psittaci infection in patients with previously unrecognized risk factors. Directed testing for C. trachomatis and C. psittaci based on clinical features and risk factors alone is likely to miss the majority of infected cases.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/genética , Chlamydophila psittaci/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Infecções Respiratórias/diagnóstico , Adolescente , Criança , Pré-Escolar , Primers do DNA/genética , DNA Bacteriano/análise , Humanos , Lactente , RNA Ribossômico 16S/genética , Infecções Respiratórias/microbiologia , Doenças Bacterianas Sexualmente Transmissíveis/diagnóstico
14.
Mol Med Rep ; 16(4): 4835-4842, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28765948

RESUMO

The obligate intracellular bacterium Chlamydia psittaci is the causative agent of psittacosis in birds and humans. The capability of this zoonotic pathogen to develop a persistent phase may serve a role in the chronicity of infections, in addition to the failure of antibiotic therapy or immunoprophylaxis. In the present study, a C. psittaci strain 6BC persistent infection cell model was induced using interferon (IFN)­Î³, alterations in the infectivity and morphology of the pathogen were analyzed, and the transcript profile of seven selected genes was analyzed. Following treatment with IFN­Î³, the infectivity of C. psittaci 6BC was decreased, the inclusion bodies appeared to be smaller, reticulate bodies were larger and the number of infectious elementary bodies was decreased compared with acute infection. In IFN­Î³­induced persistently infected cells, the relative mRNA expression levels of the genes CPSIT­0208, CPSIT­0310, CPSIT­0846, CPSIT­0844 and CPSIT­0594 were upregulated at 2­48 h post­infection (p.i.). The genes CPSIT­0959 and CPSIT­0057 were downregulated at 2­36 h p.i. The results of the present study advanced the understanding of C. psittaci persistent infection and demonstrated a number of previously unknown alterations in chlamydial gene expression, which may provide novel targets to further analyze this particular host­pathogen interaction.


Assuntos
Chlamydophila psittaci/efeitos dos fármacos , Chlamydophila psittaci/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Interferon gama/farmacologia , Psitacose/microbiologia , Transcrição Genética , Células Cultivadas , Chlamydophila psittaci/ultraestrutura , Imunofluorescência , Células HeLa , Interações Hospedeiro-Patógeno , Humanos
15.
Rev Argent Microbiol ; 49(4): 323-327, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28734713

RESUMO

In Argentina, the epidemiological and molecular characteristics of Chlamydia psittaci infections are still not sufficiently known. A total of 846 respiratory and 10 ocular samples from patients with suspected human psittacosis were tested for C. psittaci from January 2010 to March 2015. Four samples of birds related to these patients were also studied. Forty-eight samples were positive for C. psittaci by a nested PCR. The molecular characterization of twelve C. psittaci PCR-positive samples received in the National Reference Laboratory INEI-ANLIS "Dr. Carlos G. Malbrán", Buenos Aires, Argentina was performed. Eight positive samples from humans and four from birds were genotyped by ompA gene sequencing. C. psittaci genotype A was found in all human samples and in the related birds. This report contributes to our increasing knowledge of the epidemiological and molecular characteristics of C. psittaci to conduct effective surveillance of its zoonotic infections.


Assuntos
Chlamydophila psittaci , Psitacose , Zoonoses , Animais , Argentina , Aves/microbiologia , Chlamydophila psittaci/genética , Chlamydophila psittaci/isolamento & purificação , Humanos , Psitacose/epidemiologia , Psitacose/genética
17.
Avian Dis ; 61(1): 40-45, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28301242

RESUMO

Chlamydia psittaci, an obligate intracellular gram-negative bacteria, causes an important zoonotic disease in humans, namely, psittacosis. The objective of this study was to determine the persistent viability of C. psittaci at various temperature conditions. The cloacal swab samples were collected from feral and racing pigeons to find a C. psittaci field strain. The bacterial isolation showed that 1.3% of feral pigeons were PCR positive, while all samples of racing pigeons were PCR negative. Also, bacterial characterization suggested that it belonged to genotype B, which had bacterial titers 3.2 and 3.89 log 50% lethal dose/ml, respectively. A bacterial persistence test was performed, and the results showed that C. psittaci could survive at 56 C for up to 72 hr. In conclusion, C. psittaci could be found in feral pigeons in central Thailand. The bacteria can survive in equatorial temperature areas. This study was the first to report that C. psittaci could survive and has infectivity at 56 C for 72 hr. Therefore, awareness of C. psittaci infection in humans is necessary and should be a public health concern.


Assuntos
Doenças das Aves/microbiologia , Chlamydophila psittaci/fisiologia , Psitacose/veterinária , Animais , Aves , Chlamydophila psittaci/classificação , Chlamydophila psittaci/genética , Chlamydophila psittaci/isolamento & purificação , Columbidae/microbiologia , Genótipo , Filogenia , Reação em Cadeia da Polimerase , Psitacose/microbiologia , Temperatura Ambiente , Tailândia
19.
Sci Rep ; 6: 30019, 2016 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-27488134

RESUMO

Chlamydia psittaci is an avian pathogen and zoonotic agent of atypical pneumonia. The most pathogenic C. psittaci strains cluster into the 6BC clade, predicted to have recently emerged globally. Exposure to infected parrots is a risk factor with limited evidence also of an indirect exposure risk. Genome sequencing was performed on six Australian human and a single avian C. psittaci strain isolated over a 9 year period. Only one of the five human patients had explicit psittacine contact. Genomics analyses revealed that the Australian C. psittaci strains are remarkably similar, clustering tightly within the C. psittaci 6BC clade suggested to have been disseminated by South America parrot importation. Molecular clock analysis using the newly sequenced C. psittaci genomes predicted the emergence of the 6BC clade occurring approximately 2,000 years ago. These findings reveal the potential for an Australian natural reservoir of C. psittaci 6BC strains. These strains can also be isolated from seriously ill patients without explicit psittacine contact. The apparent recent and global spread of C. psittaci 6BC strains raises important questions over how this happened. Further studies may reveal whether the dissemination of this important zoonotic pathogen is linked to Australian parrot importation rather than parrots from elsewhere.


Assuntos
Chlamydophila psittaci/classificação , Chlamydophila psittaci/genética , Evolução Molecular , Psitacose/microbiologia , Psitacose/transmissão , Animais , Austrália , Chlamydophila psittaci/isolamento & purificação , Genoma Bacteriano/genética , Humanos , Papagaios/microbiologia , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Psitacose/patologia , Zoonoses/microbiologia , Zoonoses/patologia , Zoonoses/transmissão
20.
FEBS Lett ; 590(21): 3920-3940, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27397851

RESUMO

Chlamydia psittaci causes psittacosis/ornithosis in birds and is an economically important pathogen for poultry farming. It also infects nonavian domestic animals as well as rodents, and is a zoonotic human pathogen responsible for atypical pneumonia. The bacterium efficiently disseminates in host organisms causing pulmonary and systemic disease. Its rapid entry, fast replication cycle, and tight control of intracellular transport routes contribute to the host-to-host transmission and efficient growth observed with C. psittaci. Recent studies have revealed that the pathogen copes better than other chlamydial strains with proinflammatory effectors produced during the early immune reaction of infected hosts. These features likely contribute to successful infections and might explain the potent adaptation and evasion characteristics of the agent. Current findings on cell-autonomous, innate, and adaptive defenses against C. psittaci provide novel insights into the concerted immune mechanisms involved in the clearance of the pathogen. Further in-depth studies on C. psittaci and other related agents in cellular as well as animal models are needed to develop more efficient antichlamydial therapies and vaccination strategies.


Assuntos
Chlamydophila psittaci/fisiologia , Chlamydophila psittaci/patogenicidade , Psitacose/transmissão , Adaptação Fisiológica , Animais , Chlamydophila psittaci/genética , Genoma Bacteriano , Interações Hospedeiro-Patógeno , Humanos , Evasão da Resposta Imune , Psitacose/imunologia , Psitacose/veterinária
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