Abstract
BackgroundPreviously, twelve Rickettsia species were found in ticks, fleas, sheep keds (Melophagus ovinus), bats (common pipistrelle: Pipistrellus pipistrellus) and a tick-bitten patient in Xinjiang Uygur Autonomous Region (XUAR), northwestern China. Here we aimed to molecularly detect rickettsial agents in red fox (Vulpes vulpes), marbled polecat (Vormela peregusna) and their ticks.MethodsDuring 2018-2019, 12 red foxes, 1 marbled polecat and their ticks were sampled in two counties and a city of Xinjiang Uygur Autonomous Region (northwestern China). The heart, liver, spleen, lung and kidney of these 13 carnivores were dissected, followed by DNA extraction. Hard ticks were identified both morphologically and molecularly. All samples were examined for the presence of rickettsiae by amplifying four genetic markers.ResultsA total of 26 adult ticks and 28 nymphs (38 Ixodes canisuga, nine Ixodes kaiseri, six Haemaphysalis erinacei and one Dermacentor marginatus) were collected from red foxes, and four H. erinacei ticks were removed from a marbled polecat. Analysis of cytochrome c oxidase subunit I (COI) gene sequences indicated that 2-32 nucleotides differed between I. canisuga, I. kaiseri and H. erinacei from northwestern China and Europe. Rickettsia raoultii was detected in three red foxes, Candidatus Rickettsia barbariae in a red fox, Rickettsia sibirica in a red fox and a marbled polecat, and R. raoultii in two tick species (I. canisuga and D. marginatus).ConclusionsTo the best of our knowledge, I. canisuga and I. kaiseri have not been previously reported from red foxes in China. The DNA of R. sibirica and R. raoultii was detected for the first time in organs of red foxes, and R. sibirica in organs of marbled polecat. This is also the first molecular evidence for the presence of R. raoultii in I. canisuga. Our findings add to the range of tick-borne pathogens in wildlife species and associated ticks in China.
Rickettsia sibirica mongolitimonae human infection: A diagnostic challenge
