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1.
Chlamydophila psittaci and Chlamydophila abortus are the causative agents of avian chlamydiosis (psittacosis) and ovine enzootic abortion, respectively. Both pathogens are known to possess zoonotic potential. Due to their close genetic relatedness, direct and rapid species identification is difficult. In the present study, new real-time PCR assays are reported for both species. The tests are based on highly specific probes targeting the ompA gene region and were conducted as duplex PCRs including an internal amplification control. The Cp. psittaci assay successfully passed a proficiency test at national level. Examination of field samples revealed Cp. psittaci as the dominating species in birds, but also Cp. abortus in a few psittacines. Real-time PCR assays for species-specific detection of Cp. psittaci and Cp. abortus are suited for routine diagnosis, which renders them important tools for the recognition of outbreaks of psittacosis and ovine enzootic abortion.  相似文献   

2.
The role of chlamydiae as agents of a number of important animal and human diseases is still the subject of intensive research. Recently, a proposal for taxonomic reclassification of this group of obligate intracellular bacteria was published, which was based on a large amount of new data on genetic relatedness. According to this proposal, the family Chlamydiaceae now comprises two genera (Chlamydia and Chlamydophila) with 9 largely host-related species. The previously accepted classification scheme had distinguished 4 species within the genus Chlamydia. The most important animal chlamydiosis with zoonotic character is psittacosis, a systemic disease in psittacine birds of acute, protracted, chronic or subclinical manifestation. The analogous infection in domestic and wild fowl is known as ornithosis. Avian strains of C. psittaci (new classification: Chlamydophila psittaci) can also infect humans, the symptoms being mainly unspecific and influenza-like, but severe pneumonia, endocarditis and encephalitis are also known. The main group of persons facing an elevated risk of infection includes those having frequent contact with domestic and companion birds at work or in their spare time. In Germany, the annual average of notified cases is approximately 100. Cases of transmission to humans were repeatedly reported in connection with enzootic abortion in sheep (causative agent: C. psittaci or Chlamydophila abortus, respectively). Various chlamydial species occur as pathogens and commensals as well in cattle, pigs, horses, and cats. The assessment of the actual epidemiological importance is, however, often difficult because of their almost ubiquitous spread. Likewise, those strains of C. pneumoniae (new classification: Chlamydophila pneumoniae) found in several animal species can not yet be assessed for pathogenic properties. The possibilities for diagnostic detection of chlamydiae have considerably improved following the introduction of molecular methods, particularly the polymerase chain reaction (PCR), which permits direct identification from clinical specimens and differentiation of species.  相似文献   

3.
The prevalence of Chlamydophila psittaci (formerly Chlamydia psittaci) infection was assessed in 95 apparently healthy, captive Amazon parrots from three breeder collections in southeastern and west-central Brazil. Cloacal swabs from 95 birds were tested for chlamydial antigen, which was detected by direct immunofluorescence (DIF), and serum samples from 44 of these birds were tested for antibodies to C. psittaci using an enzyme-linked immunosorbent assay. The prevalences of active infection as detected by DIF were 16.7%, 22.2%, and 56.1%, and seroprevalences were 100%, 87.5%, and 60% in flocks A, B, and C, respectively. We can therefore infer that C. psittaci may be widespread in captive parrot populations in Brazil.  相似文献   

4.
Chlamydophila (C.) psittaci, a category B bioterrorism agent, causes respiratory disease in birds and psittacosis or parrot fever in man. The disease spreads aerogenically and no vaccines are available for either birds or man. Highly sensitive C. psittaci bioaerosol monitoring methods are unavailable. We evaluated: (1) dry filtration for collecting C. psittaci from contaminated air using different samplers and membrane filters, (2) impingement into different liquid collection media by use of the AGI-30 impinger and the BioSampler and (3) impaction into newly designed C. psittaci media utilizing the MAS-100 aerosol impactor. For personal bioaerosol sampling, we recommend the use of a gelatin filter in combination with the IOM inhalable dust sampler at an airflow rate of 2L/min. This allowed the detection of 10 organisms of C. psittaci by both PCR and culture. For stationary bioaerosol monitoring, sampling 1000L of air in 10min with the MAS-100 impactor and ChlamyTrap 1 impaction medium was most efficient and made it possible to detect 1 and 10 C. psittaci organisms by PCR and culture, respectively. ChlamyTrap 1 in combination with the MAS-100 impactor might also be applicable for bioaerosol monitoring of viruses.  相似文献   

5.
Psittacosis, also known as parrot fever and ornithosis, is a bacterial infection of humans that can cause severe pneumonia and other serious health problems. It is caused by Chlamydophila psittaci, formerly known as Chlamydia psittaci. From 1988 through 2003, 935 human cases of psittacosis were reported to the CDC and most resulted from exposure to infected pet birds, usually cockatiels, parakeets, parrots, and macaws. In birds, C. psittaci infection is referred to as avian chlamydiosis. Infected birds shed the bacteria through feces and nasal discharges, and humans become infected from exposure to these materials. This compendium provides information about psittacosis and avian chlamydiosis to public health officials, physicians, veterinarians, the pet bird industry, and others concerned with controlling these diseases and protecting public health. The recommendations in this compendium provide standardized procedures for controlling avian chlamydiosis in birds, a vital step to protecting human health. This document will be reviewed and revised as necessary.  相似文献   

6.
In the literature, studies of Chlamydia infection in birds have usually been confined to the search for Chlamydia (C., formerly Chlamydophila) psittaci, so that little is known about the presence of other chlamydial agents. In the present study, cloacal swabs and faeces samples of urban pigeons have been examined by real-time PCR, DNA microarray assays and partial ompA sequencing. Whilst C. psittaci was the predominant chlamydial agent in this pigeon population (75.8% of all Chlamydiaceae positives), the combined use of highly specific and sensitive molecular assays facilitated the detection of atypical serovars of C. psittaci, as well as other species of Chlamydia, such as C. abortus. Detection of C. pecorum and C. trachomatis from an avian host is reported here for the first time. Rather unexpectedly, 19.5% of all Chlamydiaceae-positive cases turned out to be infected with non-classified organisms. The considerable prevalence of these novel agents raises the question of their epidemiological importance and possible role as pathogens. Future surveys in domestic and wild birds will have to take the extended variety of chlamydial organisms into account.  相似文献   

7.
为初步调查SPF鸡感染鹦鹉热嗜性衣原体状况及相关SPF鸡胚源疫苗是否出现污染,本试验通过采集不同日龄的SPF鸡血清70份、SPF种蛋卵黄膜30份,收集市场上销售的SPF鸡胚源疫苗共41支,利用国产间接血凝试剂盒检测抗体,进口免疫荧光试剂盒分别测定其抗体、抗原阳性率,以评价SPF鸡鹦鹉热嗜性衣原体的流行状况和相关疫苗的污染状况。本试验结果显示,SPF鸡血清阳性率分别为31.4%(荧光法)、5.7%(间接血凝法);SPF种蛋阳性率33.3%,SPF鸡胚源疫苗平均阳性率31.7%。SPF鸡已经感染了鹦鹉热嗜性衣原体,且发现经鸡胚卵黄膜而传播病原的新途径,进而造成SPF鸡胚源疫苗出现衣原体污染。因此,加强SPF鸡鹦鹉热嗜性衣原体监测已势在必行。  相似文献   

8.
Chlamydophila psittaci (C. psittaci) infection was evaluated in 77 free-living nestlings of Blue-fronted Amazon parrots (Amazona aestiva) and Hyacinth macaws (Anodorhynchus hyacinthinus) in the Pantanal of Mato Grosso do Sul, Brazil. Tracheal and cloacal swab samples from 32 wild parrot and 45 macaw nestlings were submitted to semi-nested PCR, while serum samples were submitted to complement fixation test (CFT). Although all 32 Amazon parrot serum samples were negative by CFT, cloacal swabs from two birds were positive for Chlamydophila DNA by semi-nested PCR (6.3%); these positive birds were 32 and 45 days old. In macaws, tracheal and cloacal swabs were positive in 8.9% and 26.7% of the samples, respectively. Complement-fixing antibodies were detected in 4.8% of the macaw nestlings; macaw nestlings with positive findings were between 33 and 88 days old. These results indicate widespread dissemination of this pathogen in the two evaluated psittacine populations. No birds had clinical signs suggestive of chlamydiosis. To the best of our knowledge, this is the first report on C. psittaci in free-living Blue-fronted Amazon parrots and Hyacinth macaws in Brazil.  相似文献   

9.

Background

Pathogens with the zoonotic potential to infect humans, such as Campylobacter jejuni, Campylobacter coli and Chlamydophila psittaci, can be found in feral pigeons (Columba livia). Given the high density of these birds in the public parks and gardens of most cities, they may pose a direct threat to public health.

Methods

A total of 118 pigeons were captured in three samplings carried out in 2006-2007 in public parks and gardens in Madrid, Spain. Standard haematological and morphological analyses were carried out on the pigeons. PCR was used to screen for the presence of Campylobacter jejuni, C. coli and Chlamydophila psittaci. Positive samples were confirmed by DNA sequencing.

Results

The analyses demonstrated a high prevalence of Chlamydophila psittaci (52.6%) and Campylobacter jejuni (69.1%) among the birds captured. In contrast, Campylobacter coli was rarely detected (1.1%).

Conclusions

Pigeons in Madrid can carry Chlamydophila psittaci and Campylobacter jejuni. They may be asymptomatic or subclinical carriers of both pathogens.  相似文献   

10.
During 2003, 278 adult pigeons (Columba livia) and 54 birds of 11 other free-living species were caught in the various locations in the City of Zagreb, Croatia. Sera from 182 pigeons were tested for the presence of antibodies against Chlamydophila (C.) psittaci by ELISA test and 174 of them (95.6%) were found positive. Because of the high positivity rate in sera, cloacal swabs of 278 pigeons as well as 54 other species of free-living birds were tested for the presence of C. psittaci antigen. Fourty-four of the 278 pigeons (15.83%) were antigen positive, whereas all 54 of the wild birds were negative. Antigen-positive pigeons were euthanised and examined pathomorphologically and cytologically. Findings of specific antibodies and antigen of C. psittaci confirmed the high rate of infection among urban pigeons in the City of Zagreb, fortunately not among other free-living birds. Although the pigeon serovars of C. psittaci are considered to be of moderate pathogenicity for humans, the identification of 15.8% antigen-positive birds represents a potential source of infection to humans, especially for elderly people and immunodeficient patients, as well as for poultry in the Zagreb city area.  相似文献   

11.
Yang J  Ling Y  Yuan J  Pang W  He C 《Avian diseases》2011,55(1):76-81
The objective of this study was to isolate and identify suspected pathogens from peacocks and peacock farmers with severe pneumonia and to investigate its potential association with peacocks' pneumonia, caused by Chlamydophila psittaci infection. A clinical examination of infected peacocks identified birds with symptoms of anorexia, weight loss, yellowish droppings, airsacculitis, sinusitis, and conjunctivitis, whereas the infected farmers showed high fever and respiratory distress. Immunofluorescence tests detected chlamydial antigens in pharyngeal swabs (12 of 20) and lung tissue samples (four of five) from peacocks. One of four swabs taken from farmers was also positive by the same test. Specific anti-chlamydia immunoglobulin G was detected in 16 of 20 peacocks and four of four peacock farmers. The isolated pathogen was able to grow in specific-pathogen-free (SPF) chicken embryos and McCoy cell lines and was identified as Chlamydiae by immunofluorescence assay and PCR. Avian influenza virus, Newcastle disease virus, and infectious bronchitis virus were eliminated as potential causative agents after pharyngeal swabs inoculated onto the chorioallantoic membrane of embryonate eggs failed to recover viable virus. PCR and restriction fragment length polymorphism indicated the ompA gene from the isolate was similar to that of avian C. psittaci type B. Three-week-old SPF chickens challenged with the peacock isolate via intraperitoneal injection showed a typical pneumonia, airsacculitis, and splenitis. Subsequently, the inoculating strain was recovered from the lungs of challenged birds. This is the first report of C. psittaci infection in peacocks and peacock farmers.  相似文献   

12.
Endemic free-ranging Galapagos doves (Zenaida galapagoensis) and introduced rock doves (Columba livia) were surveyed in several islands of the Galapagos archipelago to establish sample prevalence of hemoparasites, Trichomonas gallinae, Chlamydophila psittaci, and Salmonella species. A Haemoproteus sp., the only hemoparasite identified, was found in 89% of the Galapagos doves sampled but not in the rock doves. Trichomonas gallinae was detected by polymerase chain reaction in 44% of rock doves from San Cristobal but in none of the Galapagos doves. Chlamydophila psittaci was detected from cloacal swabs in 6% of the Galapagos doves but in none of the rock doves sampled. All positive cases of C. psittaci occurred on Espa?ola, where the crude sample prevalence was 24%. A polymerase chain reaction-based Salmonella test failed to show evidence of this organism from any birds sampled.  相似文献   

13.
In this study, we investigated the shedding of Chlamydophila psittaci in faecal samples from cage birds using PCR testing. A total of 47 faeces samples were collected from four different aviaries. Main symptoms determined after clinical investigation and owner histories of the birds showed that the birds had respiratory system problems changing from mild to severe. They also showed conjunctivitis, diarrhoea or no symptoms at all. DNA extractions from faeces were performed with the QIAamp DNA Stool Mini Kit. Following PCR with Cp. psittaci specific primers, 43 (91.5%) samples were determined to harbour-specific DNA. Only one bird from each aviary was found to be negative by PCR. As all the samples from birds showing clinical signs were PCR positive, these signs could be correlated to psittacosis in these birds. Cp. psittaci shedding in faeces was detected in all the aviaries. After restriction analysis of PCR amplicons with AluI enzyme, all the isolates showed the same RFLP (Restriction Fragment Length Polymorphism) patterns with the control Cp. psittaci DNA. PCR following QIAamp DNA stool mini kit extraction of faecal samples was found to be a rapid, specific, sensitive, reproducible test, which did not need additional nested PCR of samples.  相似文献   

14.
The avian and human pathogen Chlamydophila (C.) psittaci represents a genetically heterogeneous species. To facilitate epidemiological surveys, more rapid yet highly specific molecular tests are needed. Currently used typing methods, i.e. serotyping and PCR-RFLP, have only limited sensitivity and are incapable of covering the wide spectrum of naturally occurring types of C. psittaci strains. In the present study, a new DNA microarray assay based on the ArrayTube (AT) technology was used to genotype C. psittaci in 98 isolates and 23 clinical tissue samples. The present array carries 35 oligonucleotide probes derived from variable domains 2 and 4 of the ompA gene. The assay proved highly sensitive, allowing correct genotyping of DNA from 2 inclusion-forming units. The results of DNA microarray genotyping of cultured strains proved highly concordant with the data from PCR-RFLP typing and serotyping. Sequencing of the ompA gene served as the reference test to verify the accuracy of AT genotyping results. In 15 instances (15.3%), strains were successfully typed by the AT assay, while serotyping and/or PCR-RFLP genotyping failed to produce unambiguous results. Eleven of these samples were ompA sequenced to confirm the AT findings. In addition to the currently accepted nine ompA genotypes, the microarray test was shown to recognise new provisional genotypes, such as Mat116 and YP84. In conclusion, the new AT assay proved to be suitable for rapid, sensitive and reproducible genotyping of C. psittaci strains and can be recommended for routine diagnosis.  相似文献   

15.
OBJECTIVE: To study the occurrence of Chlamydia psittaci in domesticated and wild birds and compare the sensitivity of molecular detection with cell culture isolation. DESIGN: Study of cell culture isolation and PCR detection of C psittaci in avian samples. PROCEDURE: Samples were obtained from 485 birds. Domesticated birds were selected at random from pet shops, private aviaries and zoos, while wild birds were captured locally, sampled, and immediately released. Swabs were collected from choanal slit, conjunctiva and cloaca of each bird and pooled. Samples were divided into equal portions for use in PCR dot-blot and cell culture detection. PCR and dot-blot detection was based on the ompB gene. RESULTS: Prevalence of infection varied markedly between flocks of captive birds. It was highest where there were frequent changes in the flock members or where there were many birds confined in small areas. C psittaci was not detected in wild birds or water birds. The sensitivity of cell culture compared to PCR dot-blot detection was 68%. All samples positive by cell culture were also positive by PCR. CONCLUSIONS: PCR-dot blot detection of C psittaci in birds appears to be more sensitive than cell culture isolation in this study. C psittaci infection of birds may occur in clinically normal captive birds.  相似文献   

16.
In 2005, an outbreak of severe respiratory disease in a mixed poultry flock that was infected with Chlamydophila (C.) psittaci led to dissemination of the infection to at least 100 small poultry farms in 11 districts of Central Germany. At the same time, a total of 24 persons in contact with poultry from one of the flocks reported flu-like symptoms to their physician, thus suggesting zoonotic transmission. Within 3 weeks, seven individuals had to be hospitalized, with three of them requiring intensive care. Analysis of ompA sequences from chlamydial isolates and directly from clinical samples revealed the presence of both genotype A and E/B of C. psittaci at the source of the outbreak and in contact flocks. Genotype A was also detected in the three severely ill patients. The findings of the present study demonstrate the high zoonotic potential of avian chlamydiae. To ensure speedy eradication of psittacosis in poultry flocks and effective treatment of infected humans, fast, sensitive and species-specific detection of the causative agent is essential, as well as close collaboration between regional public health services, attending physicians and the diagnostic laboratories involved.  相似文献   

17.
Two hundred and thirty six semen samples were collected from 120 bulls, 60 buffalo-bulls, and 56 rams located on farms of known history of infection with Chlamydophila species. All semen samples were examined by polymerase chain reaction (PCR) and cell culture techniques for detection of Chlamydophila species. The primers were selected to allow the amplification of all target species in a single reaction by identifying conserved sequences in the omp2 gene. PCR assay detected more positive samples (36) from the semen samples collected from different animal species than were detected by the culture method (21). The results indicated that all culture-positive semen samples (21) from different species were PCR positive. The detection limit of the PCR assay was determined with DNA extracted from fourfold serial dilution of C. abortus (B577) and C. pecorum (11/88) cultures and found to be 0.25 inclusion-forming units (IFU) per PCR, while the culture method could not detect less than 4 IFU. This is the first report using PCR for the detection of Chlamydophila species in buffalo-bulls' semen and the assay provides a simple, sensitive, rapid, and reliable means for the detection and identification of the organism.  相似文献   

18.
Feral pigeons (Columba livia domestica), which thrive in most European towns and cities, are commonly infected with the zoonotic bacterium Chlamydophila psittaci, the agent of psittacosis (also known as ornithosis) in humans. A number of surveys carried out over the last thirty years across Europe have detected high seropositivity values and high percentages of infection in feral pigeon populations. Overall, when considering data from 11 European countries, seropositivity values to C. psittaci in the sampled populations ranged from 19.4% to 95.6%. In most surveys, the complement fixation test was used, and antibodies were detected in 19.4-66.3% of the samples, with a median of 46.1%. Indirect immunofluorescence and ELISA tests were employed less frequently, but led to the detection of higher percentages of seropositivity (23.7-67.7% and 35.9-95.6%, respectively). Attempts to grow C. psittaci in cell culture or embryonated chicken eggs were successful in 2-42.3% and 0-57.1% of samples, respectively, antigen detection methods were positive in 2.3-40% of samples, while conventional PCR and real-time PCR using different genomic targets detected the organism in 3.4-50% of samples. Twenty-five C. psittaci isolates from pigeons were typed as ompA genotype B (n=14), E (n=10) and E/B (n=1). The huge increase of feral pigeon populations in Europe is a major cause of concern for the detrimental effect of pigeon droppings on environmental hygiene, in addition to the extensive damage due to the fouling of buildings and monuments. The most important pathogenic organism transmissible from feral pigeons to humans is C. psittaci, with 101 cases of disease reported in the literature. Exposure to C. psittaci-contaminated dust, direct contact with pigeons through handling and, to a lesser extent, through pigeon feeding have been identified as hazardous exposures in more than half of the human cases, while loose or transient contacts with feral pigeons have been mentioned in about 40% of the cases. Education initiatives as to the communication of a health risk resulting from contact with pigeons and pigeon excreta should primarily be targeted at individuals who may be exposed to C. psittaci-contaminated dust, such as demolition/construction workers. Recommendations to this category of workers include wearing protective clothes with hoods, boots, gloves and air filter face masks when removing pigeon faeces from roofs, garrets and buildings, especially if working indoors. Monitoring for C. psittaci infections in these workers over time should also be considered. Children should be warned not to handle sick or dead pigeons, and immunocompromised individuals should be advised to carefully limit their contact to feral pigeons. Culling of pigeons by shooting or poisoning is both unethical and ineffective as the place of the killed birds in the population is quickly filled by new juveniles or immigrating birds from neighbouring areas. Pigeon-deterring systems, such as nets and plastic or metal spikes applied to buildings and monuments will prevent their fouling, and the administration of contraceptive drugs may allow size regulation of the pigeon populations. Nevertheless, the measure that will ultimately lead to permanent reduction and will establish healthy sustainable populations is the restriction of indiscriminate feeding by pigeon lovers. The erection of dovecotes and artificial breeding facilities should be considered for providing shelter and a balanced diet to the birds, as well as a chance of interaction for pigeon lovers in a hygienically controlled environment.  相似文献   

19.
Zhang F  Li S  Yang J  Pang W  Yang L  He C 《Avian diseases》2008,52(1):74-78
The objective of this study was to isolate and identify a hypothetical Chlamydiaceae pathogen from laying hens with an oviduct cyst, and to characterize its potential causal relation with decreased egg production. Our clinical survey showed that cystic oviducts were prevalent at rates of 10% and 15.1% in breeder and commercial hen flocks, respectively. Chlamydial antigens were detected in 20 of 50 pharyngeal swabs (40%) and in 17 of 20 oviduct tissues (85%) using enzyme-linked immunosorbent assay (ELISA) antigen detection kits. The isolated pathogen was identified as Chlamydophila psittaci via complement fixation test, PCE-ELISA, and immunofluorescence assay. Avian influenza virus, Newcastle disease virus, and infectious bronchitis virus were excluded after oviduct tissues were inoculated onto the chorioallantoic membrane of embryonating eggs. The nucleotide sequence of the omp1 gene (accession no. EF202608) from the isolate was similar to that of C. psittaci avian type C (accession no. L25436). Typical cystic oviducts were observed in specific-pathogen-free hens inoculated intraperitoneally with the isolate. The high presence of chlamydial antigen is consistent with the cystic oviducts and poor egg production. We conclude that the isolated C psittaci is most likely associated with cystic oviducts in laying hens.  相似文献   

20.
Fifty-eight blue-fronted Amazon parrot (Amazona aestiva) nestlings, recovered from the illegal trade, became ill at a wildlife rehabilitation center in S?o Paulo State, Brazil. Clinical signs observed were nonspecific, and the mortality rate was 96.5% despite initial treatment with norfloxacin. Postmortem examinations were performed on 10 birds. Liver and spleen smears showed structures suggestive of Chlamydophila psittaci in four cases. Diagnosis was confirmed by seminested polymerase chain reaction on tissue samples. Other birds from the same location showed no clinical signs of the disease, although high complement fixation titers to C. psittaci were found in 10 adult psittacines. All birds in the facility were treated with doxycycline. The two surviving nestlings did not recover after two doxycycline treatments and were euthanatized. The high mortality rate observed in this outbreak was attributed to poor conditions of husbandry and delays in the diagnosis and treatment of the disease. After diagnosis, improved control measures for chlamydiosis were instituted.  相似文献   

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