Novel sequence types of Chlamydia pecorum infect free-ranging Alpine ibex (Capra ibex) and red deer (Cervus elaphus) in Switzerland.

Chlamydia pecorum, a recognized pathogen of domesticated ruminants and koalas (Phascolarctos cinereus), has been recently reported in a broad range of other wildlife species including water buffalo (Bubalus bubalis), ibex (Capra ibex), chamois (Rupicapra rupicapra), red deer (Cervus elaphus), and birds. This identification raises questions as to whether cross-host transmission may be a factor in the epidemiology of infections in these species. To begin to address this question, we employed a C. pecorum species-specific multi-locus sequence typing (MLST) scheme to characterize a small collection of C. pecorum-positive samples from wild, free-range ibex, a chamois, and a red deer from Grison, Switzerland, a canton where domesticated and wild ruminants graze in close proximity during the summer. Screening by PCR confirmed low to moderate levels of Chlamydia pecorum DNA in the eyes of healthy ibex (n = 4) and in the deer fecal sample (n = 1). The MLST analysis revealed three novel sequence types (STs; 88, 90, and 89) in these samples. On phylogenetic analysis, the ibex and deer sequences clustered by host species in their own well-supported clades and away from C. pecorum STs found in other hosts. Even though the analyzed sample size was small, the identification of unique C. pecorum STs infecting free-ranging Alpine ibex and red deer provides useful information for further C. pecorum epidemiologic studies.