The etiology remains unknown in many cases of bovine abortion in Switzerland. Bacteria of the Chlamydiales order are known abortive agents, therefore cases of bovine abortion from three ...representative regions of Switzerland were investigated in this study. Particularly Chlamydiaceae as well as the Chlamydia-like organisms Waddlia and Parachlamydia were of interest, especially because of their possible zoonotic potential. Placenta samples (n=343) were tested for these bacteria by different PCR-methods, immunohistochemistry and serology for Chlamydia abortus. Additionally an attempt for the isolation of Waddlia and Parachlamydia was made by co-cultivation in amoebae.
In 67.3% of the 343 cases a necrotizing and/or purulent placentitis was found histologically. By real-time PCR, 0.9% (3/343) of the cases were positive for Waddlia, 13.4% (46/343) positive for Parachlamydia and 14.6% (50/343) positive or questionable positive for Chlamydiaceae. Of these samples, confirmation by immunohistochemistry was possible in 2/3 cases for Waddlia, 25/46 for Parachlamydia and 4/50 for Chlamydiaceae. Of the 50 cases positive or questionable positive for Chlamydiaceae, species-identification by ArrayTube Microarray or 16S rRNA PCR resulted in 41 cases positive for C. abortus whereas the presence of Chlamydia suis was confirmed in four and Chlamydia pecorum in one case.
This study brought evidence for the importance of different members of Chlamydiales in different regions of Switzerland although Waddlia is not occurring in a high prevalence. On the other hand mixed infections with different Chlamydiales as well as with other abortigenic agents could be found.
Summary
Gill disease in salmonids is characterized by a multifactorial aetiology. Epitheliocystis of the gill lamellae caused by obligate intracellular bacteria of the order Chlamydiales is one known ...factor; however, their diversity has greatly complicated analyses to establish a causal relationship. In addition, tracing infections to a potential environmental source is currently impossible. In this study, we address these questions by investigating a wild brown trout (Salmo trutta) population from seven different sites within a Swiss river system. One age class of fish was followed over 18 months. Epitheliocystis occurred in a site‐specific pattern, associated with peak water temperatures during summer months. No evidence of a persistent infection was found within the brown trout population, implying an as yet unknown environmental source. For the first time, we detected ‘Candidatus Piscichlamydia salmonis’ and ‘Candidatus Clavochlamydia salmonicola’ infections in the same salmonid population, including dual infections within the same fish. These organisms are strongly implicated in gill disease of caged Atlantic salmon in Norway and Ireland. The absence of aquaculture production within this river system and the distance from the sea, suggests a freshwater origin for both these bacteria and offers new possibilities to explore their ecology free from aquaculture influences.
Ticks are well known to be important vectors for a wide range of bacteria, viruses and protozoa affecting human and animal health. Ixodid ticks are widely distributed in Sardinia, and an increasing ...number of tick-borne bacteria have been documented in the island. A growing number of evidence are supporting the hypothesis of alternative transmission routes for chlamydial bacteria such as the involvement of vectors. This study was conducted to provide possible molecular detection of members belonging to the
Chlamydiales
order in Sardinian ticks and to update information concerning the presence of new ectoparasite-borne bacteria in ticks collected from domestic and wild hosts in a typical Mediterranean environment. A total of 378 ticks were individually screened with a pan-
Chlamydiales
specific primers targeting the 16S rRNA gene.
Chlamydiales
DNA was detected in 28% of the total ticks analyzed. The analyses of sequences highlighted that
Rhipicephalus sanguineus
sensu lato,
Rhipicephalus bursa
,
Rhipicephalus annulatus
,
Haemaphysalis sulcata
,
Haemaphysalis punctata
and
Dermacentor marginatus
ticks exhibited DNA of
Chlamydiaceae
and
Parachlamydiaceae
members. Our results revealed that DNA of zoonotic microorganisms such as
C. psittaci
,
C. abortus
and the emerging pathogen
Parachlamydia acanthamoebae
are present in Sardinian ticks. Since routes of Chlamydia transmission are yet to be fully defined, the role of ticks as possible vectors for
Chlamydiales
remains the most challenging and interesting question to be addressed in future research. Continued monitoring of these pathogens in tick vectors is needed to provide strategies for controlling of possible chlamydial infections and disease outbreaks in the island.
The phylum Chlamydiae contains obligate intracellular bacteria, several of which cause disease in their hosts. Morphological studies have suggested that this group of bacteria may be pathogens of ...fish, causing cysts in epithelial tissue - epitheliocystis. Recently, the first genetic evidence of a chlamydial aetiology of this disease in seawater reared Atlantic salmon from Norway and Ireland was presented, and the agent was given the name 'Candidatus Piscichlamydia salmonis'. In this article we present molecular evidence for the existence of a novel Chlamydiae that also may cause epitheliocystis in Norwegian salmonids. This novel Chlamydiae has been found in salmonid fish from freshwater, and based on its partial 16S rRNA gene, it may constitute a third genus in the family Chlamydiaceae, or a closely related sister family. By using whole-mount RNA-RNA hybridization we demonstrate how infected cells are distributed in a patchy manner on a gill arch. The morphology of the novel Chlamydiae includes the characteristic head-and-tail cells that have been described earlier from salmonid fish suffering from epitheliocystis. We propose the name 'Candidatus Clavochlamydia salmonicola' for this agent of epitheliocystis in freshwater salmonids.
Recently, a PCR protocol (16SG), targeting 16S rRNA gene coupled with high resolution melt (HRM) curve analysis was developed in our laboratory and shown to reliably detect and identify the seven ...different
Chlamydiaceae spp. In this study, the potential of this method was assessed for detection and differentiation of Chlamydiosis in clinical specimens. Of the total number of 733 specimens from a range of animal species, 219 (30%) were found positive by 16SG PCR. When a sufficient amount of DNA was available (64 submissions), amplicons generated by the 16SG PCR were subjected to HRM curve analysis and results were compared to that of nucleotide sequencing. In all instances, the infecting
Chlamydiaceae spp. was genotyped according to the identity of its nucleotide sequence to a reference species. Analysis of the HRM curves and nucleotide sequences from 16SG PCR amplicons also revealed the occurrence of a
Chlamydophila-like, a
Parachlamydia-like and a variant of
Chlamydophila psittaci in chickens.
These results reveal the potential of 16SG PCR-HRM curve analysis for rapid and simultaneous detection and identification of
Chlamydiaceae spp. in animals and demonstrate the capacity of this system for rapid identification of new
Chlamydiaceae spp. in animals during routine diagnostic testings.
We investigated the zoonotic potential of Waddlia chon-drophila, a new Chlamydia-like abortigenic agent in ruminants. Anti-Waddlia antibody reactivity was tested by immunofluorescence and Western ...blot. Waddlia seroprevalence was higher in women who had had sporadic and recurrent miscarriages than in control women (p < 0.001). Waddlia spp. may represent a cause of human fetal loss.
Water-filtered infrared A (wIRA) is radiation with a spectrum ranging from 780 to 1400nm. Chlamydiaceae are obligate intracellular bacteria associated with various diseases in both animals and ...humans. A recent in vitro study demonstrated that wIRA combined with visible light (wIRA/VIS) has potential as a non-chemical method for the treatment of chlamydial infections without adversely affecting the cell viability. The aim of this study was to investigate the influence of various factors on the effect of wIRA/VIS on acute chlamydial infection, namely the impact of temperature, exposure intensity and infectious dose (multiplicity of infection) as well as the efficacy of the visible light component. We demonstrate that non-thermal effects contribute to the inhibition of acute chlamydial infection. Visible light enhances the inhibitory effect of wIRA on extracellular bacteria (elementary bodies or EBs). Moreover, the inhibitory effect of wIRA/VIS following treatment of EBs prior to infection correlated with increased irradiation intensity. The infectivity of mature chlamydial inclusions was significantly reduced upon wIRA/VIS exposure at all irradiation intensities investigated, suggesting the contribution of host cell factors to the anti-chlamydial effect of wIRA/VIS in the late stage of the developmental cycle. The effect of irradiation was not influenced by the infectious dose.
•Water-filtered infrared A combined with visible light was applied to acute chlamydial infection.•Non-thermal effects contribute to the anti-chlamydial effect of wIRA/VIS irradiation.•Visible light markedly enhances the inhibitory effect of wIRA on extracellular Chlamydia.•The effect of irradiation on extracellular Chlamydia depends on the exposure intensity.•The infectivity of mature Chlamydia is reduced regardless of the irradiation dose.
The seroprevalence of Chlamydiaceae infection in Tibetan pigs in Tibet, China, was examined by indirect hemagglutination assay (IHA), between April, 2010, and December, 2010. A total of 71 of 427 ...serum samples (16.63%, 95% confidence interval CI 15.31-17.95 were positive for Chlamydiaceae antibodies. Forty Chlamydiaceae seropositives from 232 samples were recorded in sera from Nyingchi (17.24%, 95% CI 15.40-19.08) and 31 positives were recorded in 195 serum samples from Mainling (15.90%, 95% CI 14.02-17.78). The investigation showed that the prevalence in female animals was 17.61% (95% CI 15.22-20.00), and in male animals it was 12.72% (95% CI 11.07-14.37). The prevalence ranged from 0% to 20.61% (95% CI 17.81-23.48) among different age groups, with a higher prevalence in growing pigs (p<0.01). The results indicated that Chlamydiaceae infection was widespread in Tibetan pigs in Tibet, China, which is of public health concern in this region of the world. To our knowledge, this is the first report of Chlamydiaceae seroprevalence in Tibetan pigs in Tibet, China.
Few data are available on the prevalence and relevance of chlamydiae in wild mammals, and even fewer studies have been conducted to determine the prevalence of
Chlamydophila abortus in wildlife ...hosts, most probably due to the absence of suitable species-specific serological assays for testing sera from wild animals. In light of this, we have developed two in-house blocking-ELISA tests for detection of antibodies against
Chlamydiaceae and
C. abortus in wild ungulates, and analyzed the relationship between geographical and biological factors and the prevalence of antibodies against
Chlamydiaceae and
C. abortus in 434 wild ungulates from Spain, including sera from European wild boar, Red deer, Fallow deer, Roe deer, Mouflon, Barbary sheep, Southern chamois, and Iberian ibex. Serology revealed that 41.7
±
4% of the sera were positive for the b-ELISA-LPS (
Chlamydiaceae-specific) and 18.9
±
3% for the b-ELISA-rPOMP (
C. abortus-specific). Antibodies against
Chlamydiaceae lipopolysaccharide (LPS) were detected in sera from all eight ungulate species, the prevalence ranging from 23 to 60%. Iberian ibex was the only wild ungulate not showing seropositivity to the
C. abortus specific polymorphic outer membrane protein (POMP). The prevalence of anti-POMP antibodies in the other seven wild ungulate species ranged from 7 to 40%. While significant seroprevalence differences were detected among species and among sampling regions, no effect of age and sex was observed. The high prevalence levels found should be considered with regards to livestock and human health, and warrant further research.