Chlamydiae in Free-Ranging and Captive Frogs in Switzerland

Abstract

A total of 210 frog samples originating either from a mass mortality (1991/1992) or from routine postmortem investigations of the years 1990 to 2004 were examined retrospectively for a possible involvement of Chlamydiae. For a prevalence study of Chlamydia in a selected Swiss amphibian population, 403 samples from free-ranging Rana temporaria were examined. Histopathology, immunohistochemistry using a monoclonal antibody against chlamydial lipopolysaccharide, and a 16S rRNA polymerase chain reaction (PCR) followed by DNA sequencing were performed on the formalin-fixed and paraffin-embedded tissues. Using PCR, 8 of 54 (14.8%) frog samples from the mass mortality (1991/1992) were positive for Chlamydia suis S45. A control group of healthy Xenopus laevis had 3 of 38 positive samples, sequenced as C suis S45 (2/3) and an endosymbiont of Acanthamoeba species UWE1 (1/3). Chlamydophila pneumoniae TW-183 was detected from exotic frogs kept in a zoo. Of the frogs collected for the prevalence study, 6 of 238 (2.5%) tested positive, 1 each for C suis S45, Cp pneumoniae TW-183, and uncultured Chlamydiales CRG22, and the remaining 3 revealed Chlamydophila abortus S26/3. In immunohistochemistry, there were 2 positive labeling reactions, 1 in intestine and the other in the epithelium coating the body cavity, both testing positive for Cp pneumoniae TW-183 in PCR. Histologically there were no lesions recorded being characteristic for Chlamydia. Although there is a prevalence of Chlamydia in Swiss frogs, no connection to a mass mortality (1991/1992) could be established. For the first time, C suis S45 and Cp abortus S26/3 were detected in frog material.

The novel ‘CandidatusAmphibiichlamydia ranarum’ is highly prevalent in invasive exotic bullfrogs (Lithobates catesbeianus)

“…The presence of the novel taxon in the bullfrogs tadpoles was not associated with obvious clinical disease, resembling results obtained by Blumer and colleagues (2007), who found a prevalence of 2.5% of Chlamydiales in 126 Rana temporaria without a clear link with disease. However, its closest relative ‘ Candidatus Amphibiichlamydia salamandrae’ has been associated with severe disease and high mortality (Martel et al ., 2012).…”

Intraspecific Variation in the Skin-Associated Microbiome of a Terrestrial Salamander

“…To date, all known members of Chlamydiaceae are intracellular parasites, and are known to cause disease in many animals [59]. Yet Chlamydia has rarely been recorded in amphibians, and its pathogenicity is unclear [60]. In any case, such low core community abundance and dominance of Chlamydiaceae may be an example of dysbiosis, or disruption of a normal, healthy microbiome.…”

Characterisation of Chlamydia pneumoniae and other novel chlamydial infections in captive snakes

“…While chlamydiosis has been described in a number of reptiles and amphibians, different chlamydial species have been implicated (Berger et al, 1999;Soldati et al, 2004;Blumer et al, 2007;Robertson et al, 2010;Martel et al, 2013). C. pneumoniae, on the other hand, has been described more widely in reptiles such as snakes, iguanas and chameleons (Bodetti et al, 2002;Jacobson et al, 2002;Jacobson et al, 2004).…”