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1.
To determine the prevalence of Chlamydophila psittaci in wild birds, cloacal swabs from 527 songbirds, 442 waterfowl, 84 feral pigeons, and 38 cormorants were examined by Chlamydiaceae-specific real-time polymerase chain reaction (PCR) and ArrayTube microarray assays for chlamydial species determination and genotyping of C. psittaci. Inconclusive cases were further characterized by conventional PCR methods targeting the chlamydial outer membrane protein A, 16S, 23S, and intergenic spacer genes followed by sequencing of the PCR product. Swabs of 19 water birds (tufted ducks and pochards), 12 pigeons, and one songbird were tested positive by the Chlamydiaceae-specific real-time PCR. While C. psittaci genotypes B (n = 5) and E (n = 1) were identified in feral pigeons (n = 9), the genotype could not be identified in the remaining three cases. Sequence data of Chlamydiaceae-positive cases (n = 23; 19 waterfowl, three pigeons, one songbird) indicated the presence of nonclassified chlamydial agents (n = 20) and C. psittaci (n = 3) by 16S rRNA PCR and sequencing. In conclusion, C. psittaci was not detected in waterfowl and songbirds, but C. psittaci proved prevalent in urban feral pigeons, where it poses a significant risk for humans.  相似文献   

2.
In many cities, the feral rock dove is an abundant bird species that can harbor Chlamydophila psittaci. We determined the prevalence and genotype of C. psittaci in fresh fecal samples from feral pigeons in Amsterdam, The Netherlands. The prevalence was 7.9% overall (26/331; 95% confidence interval, 5 to 11). Ten genotyped PCR-positive samples were all genotype B.  相似文献   

3.
Chlamydia psittaci is an obligate intracellular bacterium responsible for avian chlamydiosis, otherwise known as psittacosis, a zoonotic disease that may lead to severe atypical pneumonia. This study was conducted on seven mule duck flocks harboring asymptomatic birds to explore the circulation and persistence of C. psittaci during the entire breeding process and assess the potential sources of worker exposure. Cloacal swabs and air samples were taken on each occasion requiring humans to handle the birds. In parallel, environmental samples, including dust, water, and soil, were collected. Specific real-time PCR analyses revealed the presence of C. psittaci in all flocks but with three different shedding patterns involving ducks about the age of 4, 8, and 12 weeks with heavy, moderate, and low excretion levels, respectively. Air samples were only positive in flocks harboring heavy shedders. Dust in flocks with heavy or moderate shedders carried chlamydial loads strongly associated with the loads detected in avian and soil samples. Environmental contamination, significantly correlated with shedding dynamics, was considered to be the most probable source of exposure. The high prevalence of bacteriophage Chp1 in all flocks, mostly jointly present with chlamydia, suggests an important factor in C. psittaci persistence, thus creating a greater risk for humans. A survey conducted in these flocks regarding farming practices and activities showed that disinfection seems to be the most promising practice for reducing C. psittaci prevalence in ducks and that the place and the duration of action during operations seem to be potential risk factors. Strict adherence to good practices is strongly recommended.  相似文献   

4.
Chlamydia psittaci primarily infects birds, but zoonotic transmission occurs in people in close contact with infected birds. The clinical outcome ranges from inapparent disease to pneumonia. Here we report the genome sequences of all 9 Chlamydia psittaci genotype reference strains.  相似文献   

5.
RFLP analysis of the omp1 gene was used to characterize 51 avian Chlamydophila psittaci isolates. The analysis confirmed the predominance of genotype A in parrot C. psittaci isolates and revealed new omp1 genotypes in corvid C. psittaci isolates. The corvid isolates proved to lack an extrachromosomal plasmid. The omp1 and rRNA IGS sequences were determined for the new isolates. Phylogenetic analysis showed that isolate 1V, obtained from a crow, is intermediate in several characters between C. abortus and C. psittaci. The results were compared with data on the phylogenetic relationships of earlier chlamydium isolates.  相似文献   

6.
Because many people visit zoos, prevention of zoonoses is important from the standpoint of public health. This study examined the prevalence of Chlamydia among zoo animals in Japan by PCR and characterized these bacteria by performing phylogenetic analyses of the sequences of the variable domain (VD) 2 and VD4 regions of the ompA gene, which encodes the Chlamydia major outer membrane protein. Fecal samples were collected from 1150 zoo animals in five zoos and examined for Chlamydia DNA. Chlamydia psittaci DNA was found in 3.9% of mammals, 7.2% of birds and 8.1% of reptiles. The prevalence of Chlamydia pneumoniae DNA was significantly higher in reptiles (5.8%) than in mammals (0.3%) and birds (0.3%). Phylogenetic analysis of the ompA VD2 region from 18 samples showed that nine were in three different clusters containing C. psittaci strains, six were in a cluster containing C. pneumoniae strains and three each formed a distinct branch. Furthermore, phylogenetic analysis of the ompA VD4 region showed that C. pneumoniae DNAs from reptiles were close to those from human patients. The C. pneumoniae DNAs from the European glass lizard, Emerald tree boa, and Panther chameleon were classified in clusters that were distinct from other strains, suggesting that these reptiles had each been infected with a specific C. pneumoniae genotype. This study showed that diverse Chlamydia strains have been prevalent among a variety of zoo animals.  相似文献   

7.
Birds are the primary hosts of Chlamydia psittaci, a bacterium that can cause avian chlamydiosis in birds and psittacosis in humans. Wild seabirds are frequently admitted to wildlife rescue centers (WRC) at European Atlantic coasts, for example, in connection with oil spills. To investigate the extent of chlamydial shedding by these birds and the resulting risk for animals in care and the medical staff, seabirds from a French WRC were sampled from May 2011 to January 2014. By use of a quantitative PCR (qPCR), 195 seabirds belonging to 4 orders, 5 families and 13 species were examined, of which 18.5% proved to be Chlamydiaceae positive. The highest prevalence of shedders was found in northern gannets (Morus bassanus) (41%), followed by European herring gulls (Larus argentatus) (14%) and common murres (Uria aalge) (7%). Molecular characterization and phylogenetic analysis of qPCR-positive northern gannet samples revealed two variants of a strain closely related to C. psittaci. In European herring gulls and in one common murre, strains showing high sequence similarity to the atypical Chlamydiaceae-like C122 previously found in gulls were detected. Our study shows that seabirds from the northeastern Atlantic Ocean carry several chlamydial organisms, including C. psittaci-related strains. The staff in WRCs should take protective measures, particularly in the case of mass admissions of seabirds.  相似文献   

8.
Recent evidence of the occurrence of atypical Chlamydiaceae strains in pigeons, different from the established Chlamydiaceae, requires the development of a specific and rapid detection tool to investigate their prevalence and significance. Here is described a new real-time PCR assay that allows specific detection of atypical Chlamydiaceae from pigeons. The assay has been used to assess the dissemination of these strains in field samples collected from Parisian pigeon populations in 2009. The results suggest a limited dissemination compared to the usually higher prevalence of Chlamydia psittaci that is the main species associated with avian chlamydiosis.  相似文献   

9.
The prevalence of infectious diseases in wild and feral carnivores is poorly known in Primorsky Krai, where rare species such as the Amur tiger and the Far East leopard roam. In this study we evaluated the prevalence of seropositivity in feral (cats, dogs) and wild (raccoon dog, badger, American mink, Far Eastern wild cat) carnivores to various pathogens: distemper virus, parvovirus, feline immunodeficiency and feline leukemia virus, feline coronavirus, Toxoplasma gondii, Mycoplasma sp., and Chlamydia sp. It was shown that seropositivity occurred significantly more frequent in feral animals than in wild ones. The highest percentage of seropositive animals was observed in feral dogs. It is these diseases that can be dangerous for the Amur tiger and the Far East leopard, thus affecting their populations.  相似文献   

10.
The quokka, Setonix brachyurus, is a vulnerable, small marsupial endemic to Western Australia. Blood samples were collected from quokkas from three different geographical locations; Two Peoples Bay, Bald Island and Rottnest Island. The overall prevalence of trypanosomes by nested PCR at the 18S ribosomal RNA gene was 57.3% (63/110) with prevalences of 91.4%, 85.3% and 4.9% respectively for Two Peoples Bay, Bald Island and Rottnest Island. Phylogenetic analysis conducted on 47 18S PCR positives identified two Trypanosoma copemani genotypes, with T. copemani genotype B, the most prevalent genotype infecting quokka populations from the three locations with an overall prevalence of 51.8% (24/47) compared to 34% for T. copemani genotype A (16/47). The overall prevalence of mixed T. copemani genotype A and B infections was 14.9% (7/47). Phylogenetic analysis of 26 quokka isolates at the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) locus, largely supported the 18S analysis but identified a mixed infection in one quokka isolate (Q4112-4117 from Two Peoples Bay). T. copemani genotype B has previously only been isolated from quokkas and the Gilbert's potoroo whereas T. copemani genotype A has a wide host range and may be pathogenic. Further work is required to determine the clinical impact of T. copemani on marsupial populations.  相似文献   

11.
The prevalence and genotype of Toxoplasma gondii infection in dogs in Henan Province, Central China was investigated. A total of 125 blood samples were collected from pet dogs during April to June 2013, and all samples were examined by indirect hemagglutination antibody test (IHA) and nested PCR. The overall T. gondii prevalence in pet dogs was 24.0% (30/125), with 20.8% (26/125) in IHA and 10.4% (13/125) in PCR, respectively. No statistical associations were found between animal gender and age and the prevalence of T. gondii infection. Thirteen positive DNA samples were genotyped using 11 PCR-RFLP markers, including SAG1, (3’+5’) SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico. Of these, only 2 samples were genotyped with complete data for all loci, and a novel genotype (type III at SAG3 and GRA6 loci, and type I at other loci) was identified. This is the first report of genetic characterization of T. gondii infection in dogs in China.  相似文献   

12.
Environmental transmission of Toxoplasma gondii, a global zoonotic parasite, adversely impacts human and animal health. Toxoplasma is a significant cause of mortality in threatened Southern sea otters, which serve as sentinels for disease threats to people and animals in coastal environments. As wild and domestic felids are the only recognized hosts capable of shedding Toxoplasma oocysts into the environment, otter infection suggests land-to-sea pathogen transmission. To assess relative contributions to terrestrial parasite loading, we evaluated infection and shedding among managed and unmanaged feral domestic cats, mountain lions, and bobcats in coastal California, USA. Infection prevalence differed among sympatric felids, with a significantly lower prevalence for managed feral cats (17%) than mountain lions, bobcats, or unmanaged feral cats subsisting on wild prey (73–81%). A geographic hotspot of infection in felids was identified near Monterey Bay, bordering a high-risk site for otter infection. Increased odds of oocyst shedding were detected in bobcats and unmanaged feral cats. Due to their large populations, pet and feral domestic cats likely contribute more oocysts to lands bordering the sea otter range than native wild felids. Continued coastal development may influence felid numbers and distribution, increase terrestrial pathogens in freshwater runoff, and alter disease dynamics at the human–animal–environment interface.  相似文献   

13.

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.  相似文献   

14.
Chlamydia comprises a group of obligate intracellular bacterial parasites responsible for a variety of diseases in humans and animals, including several zoonoses. Chlamydia trachomatis causes diseases such as trachoma, urogenital infection and lymphogranuloma venereum with severe morbidity. Chlamydia pneumoniae is a common cause of community-acquired respiratory tract infections. Chlamydia psittaci, causing zoonotic pneumonia in humans, is usually hosted by birds, while Chlamydia abortus, causing abortion and fetal death in mammals, including humans, is mainly hosted by goats and sheep. We used multi-locus sequence typing to asses the population structure of Chlamydia. In total, 132 Chlamydia isolates were analyzed, including 60 C. trachomatis, 18 C. pneumoniae, 16 C. abortus, 34 C. psittaci and one of each of C. pecorum, C. caviae, C. muridarum and C. felis. Cluster analyses utilizing the Neighbour-Joining algorithm with the maximum composite likelihood model of concatenated sequences of 7 housekeeping fragments showed that C. psittaci 84/2334 isolated from a parrot grouped together with the C. abortus isolates from goats and sheep. Cluster analyses of the individual alleles showed that in all instances C. psittaci 84/2334 formed one group with C. abortus. Moving 84/2334 from the C. psittaci group to the C. abortus group resulted in a significant increase in the number of fixed differences and elimination of the number of shared mutations between C. psittaci and C. abortus. C. psittaci M56 from a muskrat branched separately from the main group of C. psittaci isolates. C. psittaci genotypes appeared to be associated with host species. The phylogentic tree of C. psittaci did not follow that of its host bird species, suggesting host species jumps. In conclusion, we report for the first time an association between C. psittaci genotypes with host species.  相似文献   

15.
The Pantanal in Brazil is the largest floodplain of the world. This ecosystem, rich in wildlife, has a large feral pig population. Such a large host biomass must have a strong influence on the parasite fauna. In this work, we evaluated the role of feral pigs in the maintenance of Amblyomma sculptum (formerly Amblyomma cajennense), the most prevalent tick species in the Pantanal. Tick infestations were evaluated on 243 feral pigs and their environment. The suitability of domestic pigs, representing their feral relatives, to A. sculptum adults and nymphs was assessed experimentally. Tick infestation of feral pigs was strongly associated with that of the environment: 96 and 97 % of the ticks, respectively, were A. sculptum. The infestation prevalence on this host species was close to 90 % in the dry season and 100 % in the wet season and mean infestation intensity was above 30 ticks in both seasons. Suitability of pigs as hosts for A. sculptum was shown by the high proportion of nymphs and female ticks found engorging on captured feral pigs and adequate biological parameters displayed by ticks from experimental infestations of domestic pigs. Other tick species on feral pigs, albeit in much lower numbers, were Amblyomma parvum and Ornithodorus rostratus. Results show that feral pigs feed a high proportion of the A. sculptum adults and nymphs in their territories and should be a target for tick-borne diseases studies. This is particularly relevant to public health because all the main tick species found on feral pigs are aggressive to humans as well.  相似文献   

16.
The potential environmental risks of transgene exposure are not clear for alfalfa (Medicago sativa subsp. sativa), a perennial crop that is cross-pollinated by insects. We gathered data on feral alfalfa in major alfalfa seed-production areas in the western United States to (1) evaluate evidence that feral transgenic plants spread transgenes and (2) determine environmental and agricultural production factors influencing the location of feral alfalfa, especially transgenic plants. Road verges in Fresno, California; Canyon, Idaho; and Walla Walla, Washington were surveyed in 2011 and 2012 for feral plants, and samples were tested for the CP4 EPSPS protein that conveys resistance to glyphosate. Of 4580 sites surveyed, feral plants were observed at 404 sites. Twenty-seven percent of these sites had transgenic plants. The frequency of sites having transgenic feral plants varied among our study areas. Transgenic plants were found in 32.7%, 21.4.7% and 8.3% of feral plant sites in Fresno, Canyon and Walla Walla, respectively. Spatial analysis suggested that feral populations started independently and tended to cluster in seed and hay production areas, places where seed tended to drop. Significant but low spatial auto correlation suggested that in some instances, plants colonized nearby locations. Neighboring feral plants were frequently within pollinator foraging range; however, further research is needed to confirm transgene flow. Locations of feral plant clusters were not well predicted by environmental and production variables. However, the likelihood of seed spillage during production and transport had predictive value in explaining the occurrence of transgenic feral populations. Our study confirms that genetically engineered alfalfa has dispersed into the environment, and suggests that minimizing seed spillage and eradicating feral alfalfa along road sides would be effective strategies to minimize transgene dispersal.  相似文献   

17.
In order to examine the prevalence of Cryptosporidium infection in wild rodents and insectivores of South Korea and to assess their potential role as a source of human cryptosporidiosis, a total of 199 wild rodents and insectivore specimens were collected from 10 regions of South Korea and screened for Cryptosporidium infection over a period of 2 years (2012-2013). A nested-PCR amplification of Cryptosporidium oocyst wall protein (COWP) gene fragment revealed an overall prevalence of 34.2% (68/199). The sequence analysis of 18S rRNA gene locus of Cryptosporidium was performed from the fecal and cecum samples that tested positive by COWP amplification PCR. As a result, we identified 4 species/genotypes; chipmunk genotype I, cervine genotype I, C. muris, and a new genotype which is closely related to the bear genotype. The new genotype isolated from 12 Apodemus agrarius and 2 Apodemus chejuensis was not previously identified as known species or genotype, and therefore, it is supposed to be a novel genotype. In addition, the host spectrum of Cryptosporidium was extended to A. agrarius and Crosidura lasiura, which had not been reported before. In this study, we found that the Korean wild rodents and insectivores were infected with various Cryptosporidium spp. with large intra-genotypic variationa, indicating that they may function as potential reservoirs transmitting zoonotic Cryptosporidium to livestock and humans.  相似文献   

18.
The prevalence of anti-chlamydia antibodies was examined in 232 cat sera collected in 1985 and from 1993 to 1995 from laboratories and veterinary hospitals located in 11 prefectures of Japan. The antibodies were determined by an indirect microimmunofluorescence test using six strains of feline Chlamydia: one strain each of avian- and guinea pig-derived C. psittaci and one strain each of C. pecorum, C. pneumoniae and C. trachomatis. Positive rates of IgG antibodies to chlamydiae were 34.4% in 1985 and 16.5–21.4% from 1993 to 1995. Positive rates of IgM antibodies to chlamydiae were 8.2% in 1985 and 6.6–14.3% from 1993 to 1995. Variations in antibody reactivity to the different feline strains were observed. The results suggest the wide prevalence of chlamydial infection in cats in Japan, and antigenic diversity in the feline strains of C. psittaci.  相似文献   

19.
A total of 289 pig faecal samples were collected from pre-weaned and post-weaned piglets and sows from 1 indoor and 3 outdoor piggeries located in the south-west region of Western Australia and screened at the 18S rRNA locus for the presence of Cryptosporidium. An overall prevalence of 22.1% (64/289) was identified. Cryptosporidium was more prevalent in post-weaned animals (p < 0.05); 32.7% (51/156) versus 10.6% (13/123) for pre-weaned animals. Sequence analysis identified Cryptosporidium suis in all pre-weaned isolates genotyped (7/13). In post-weaned pigs that were genotyped (n = 38), the non-zoonotic Cryptosporidium species, pig genotype II was identified in 32 samples and C. suis in 6 samples. The zoonotic species Cryptosporidium parvum was not detected, suggesting that domestic pigs do not pose a significant public health risk. Pig genotype II was significantly (p < 0.05) associated with ‘normal’ stools, indicating an asymptomatic nature in the porcine host.  相似文献   

20.

Background

Methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C and methionine synthase reductase (MTRR) A66G polymorphisms are important genetic determinants for homocysteine (Hcy) levels, and are associated with several disorders. These polymorphisms are heterogeneously distributed worldwide. Our objective was to explore the geographical distributions of these polymorphisms in China.

Methodologies

15357 healthy adults were recruited from 10 regions. Buccal samples were collected and genomic DNA was isolated. Genotyping was performed using the fluorogenic 5′-nuclease assay.

Principal Findings

The prevalence of the three polymorphisms among different populations from China varied significantly and showed apparent geographical gradients. For MTHFR C677T, the frequencies of the 677T allele and the 677TT genotype were significantly higher among northern populations and ranged from the lowest values (24.0% and 6.4%, respectively) in Hainan (southern) to the highest values (63.1% and 40.8%, respectively) in Shandong (northern). For MTHFR A1298C, the 1298C allele and the 1298CC genotype frequencies were significantly higher among southern populations and increased from low values (13.1% and 1.4%, respectively) in Shandong to high values (25.7% and 6.7%, respectively) in Hainan. For A66G, the 66G allele and the 66GG genotype frequencies increased from lower values (23.7% and 5.4%, respectively) in Shandong to higher values (29.2% and 8.6%, respectively) in Hainan. The overall frequency of the 677T allele, 677TT genotype, 1298C allele, 1298CC genotype, 66G allele and 66GG genotype in the Chinese Han population was 45.2%, 23.2%, 18.6%, 3.9%, 25.7%, and 6.6%, respectively. No gender differences were found in the prevalence of both the MTHFR C677T and MTRR A66G polymorphisms.

Conclusions

This study indicates that there are marked geographical variations in the prevalence of the three polymorphisms among Chinese Han populations. Our baseline data may be useful for future researches in related fields.  相似文献   

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