Chlamydiales in Guinea‐pigs and Their Zoonotic Potential

Abstract

The aim was to detect and characterize chlamydial infections in guinea-pigs (GP) with ocular disease, study their pathogenicity and zoonotic potential and to test for the presence of Acanthamoebae spp. in GP eyes and to investigate whether they could act as vectors for Chlamydia-like organisms. Overall 126 GP, of which 77 were symptomatic, were screened by clinical examination, cytology, gross pathology, histology, immunohistochemistry, polymerase chain reaction (PCR) and bacteriology. A new Chlamydiaceae-specific intergenic spacer rRNA gene PCR, designed to amplify this segment linking the 16S and 23S regions, was performed. DNA samples were also received from one owner including samples of his cat and rabbit. Guinea-pigs: 48 of 75 symptomatic, but only 11 of 48 asymptomatic GP were positive by PCR for Chlamydophila caviae guinea-pig inclusion conjunctivitis (GPIC) (P < 0.0001). Eighteen of 75 or 15/48, respectively, were positive for DNA from Chlamydia-like organisms. Acanthamoebae-DNA could be found in two GP, of which one was symptomatic. Owner, cat and rabbit: Samples of all three species were positive by PCR for C. caviae GPIC and the owner's one-day disposable contact lenses showed a positive PCR result for the Chlamydia-like organism Parachlamydia acanthamoebae. No Acanthamoebae-DNA could be detected. This study is the first to describe Chlamydia-like organisms in GP and to detect C. caviae GPIC in human, cat and rabbit. Therefore, C. caviae GPIC could pose a zoonotic potential. We believe that the finding of C. caviae GPIC in species other than GP is probably not unique.

Real-Time Detection and Identification of Chlamydophila Species in Veterinary Specimens by Using SYBR Green-Based PCR Assays

“…The Chlamydiaceae species are known to be very host specific, and in our study we identified Chlamydophila species only in their expected hosts. However, other studies have shown that one species may be isolated from various hosts (4,6,9,13,16,17). Host specificity may be viewed in terms of primary or principal hosts and occasional hosts (20), where the infection usually spreads from the primary host to occasional hosts living in close proximity.…”

“…This is illustrated in Cp. caviae isolated from the primary host (a guinea pig) but also detected in the animal's owner, as well as in a cat and a rabbit in the household (16). Usually, primary hosts are sampled because they show typical clinical signs, but the larger host diversity applicable for Chlamydophila sp.…”

Evidence of Maternal–Fetal Transmission ofParachlamydia acanthamoebae

“…Two liters of water samples were fi ltrated through 0.22-μm pore-sized fi lters that were injected onto amebal microplates as previously described (6) and incubated at 32°C. We screened amebal microplates by examination under inverted microscope and by ZiehlNielsen, Gram, and Gimenez staining.…”

“…Of interest, a recent study of 482 healthy Swiss men found 3 who were seropositive for Parachlamydia sp., and all 3 came from the same rural area near Lausanne (within <20-km radius) (9). Moreover, the patient owns 2 guinea pigs, potential vectors of the bacterium (6). Other modes of transmission are possible, e.g., contaminated water (free-living amebae may serve as hosts for Parachlamydia spp.…”

Chlamydiaceae and Chlamydia-Like Organisms in Free-Living Small Mammals in Europe and Afghanistan

“…Both are considered to be important emerging pathogens in animals with zoonotic potential (Greub and Raoult 2002) and they might be regarded as new abortigenic agents in Swiss and Scottish cows (e.g., Ruhl et al 2009;Deuchande et al 2010). Moreover, P. acanthamoebae has been associated with ocular lesions in naturally infected guinea pigs (Cavia porcellus; Lutz-Wohlgroth et al 2006) and cats (Felis catus; Richter et al 2010) and was recently shown to produce pneumonia in an experimental murine lung infection model (Casson et al 2008b). Parachlamydia and Waddlia DNA have been detected in several ruminant wildlife species in Switzerland (Regenscheit et al 2012) and even in environmental samples such as drinking and well water for cattle (Bos primigenius) (Wheelhouse et al 2011;Codony et al 2012).…”