title: 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.
authors.affiliation: Institute of Veterinary Pathology, University of Zurich, Winterthurerstrasse 268, CH-8057 Zurich, Switzerland.
authors.forename: C
authors.initials: C
authors.lastname: Blumer
authors.forename: D R
authors.initials: DR
authors.lastname: Zimmermann
authors.forename: R
authors.initials: R
authors.lastname: Weilenmann
authors.forename: L
authors.initials: L
authors.lastname: Vaughan
authors.forename: A
authors.initials: A
authors.lastname: Pospischil
mesh_terms: D000818:Animals; D001001:Anura / Q000382:microbiology*; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics; D002689:Chlamydia / Q000235:genetics / Q000254:growth & development*; D002690:Chlamydia Infections / Q000453:epidemiology* / Q000382:microbiology / Q000662:veterinary*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004196:Disease Outbreaks / Q000662:veterinary*; D007150:Immunohistochemistry / Q000662:veterinary; D016133:Polymerase Chain Reaction / Q000662:veterinary; D015995:Prevalence; D012336:RNA, Ribosomal, 16S / Q000737:chemistry / Q000235:genetics; D012189:Retrospective Studies; D017422:Sequence Analysis, DNA; D013557:Switzerland / Q000453:epidemiology
chemical_list: D001425:Bacterial Outer Membrane Proteins; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; C078167:OMPA outer membrane proteins