RESUMO
Microorganisms harbored by Chilean autochthonous ticks have been scarcely studied and current knowledge is restricted to three species of hard ticks only. The current study aimed to assess the presence of Anaplasmataceae, Borrelia and Hepatozoon agents in ticks collected directly from the environment, on reptiles, birds and mammals in twelve localities from northern, central and southern regions of the country and Antarctica. Ticks were identified by means of a morphological and molecular approach. PCR detections point the occurrence of an Anaplasma-like agent and a relapsing fever Borrelia sp. in Ornithodoros spheniscus; an Ehrlichia sp. and a Hepatozoon sp. in Ornithodoros atacamensis; "Candidatus Neoehrlichia chilensis", Borrelia burgdorferi sensu lato (s. l.), and Hepatozoon in Ixodes ticks morphologically related to the Ixodes sigelos group; and B. burgdorferi s. l. in Ixodes auritulus. Supported by phylogenetic analyses of characterized microorganisms, this study introduces putative vector roles and initial evidence on possible new agents detected in Chilean ticks.
Assuntos
Anaplasmataceae/isolamento & purificação , Borrelia/isolamento & purificação , Vetores de Doenças , Ehrlichia/isolamento & purificação , Geografia , Ixodes/microbiologia , Ornithodoros/microbiologia , Anaplasmataceae/genética , Animais , Regiões Antárticas , Borrelia/genética , Chile , Ehrlichia/genéticaRESUMO
Recently, the incidence and awareness of tick-borne diseases in humans and animals have increased due to several factors, which in association favor the chances of contact among wild animals and their ectoparasites, domestic animals and humans. Wild and domestic carnivores are considered the primary source of tick-borne zoonotic agents to humans. Among emergent tick-borne pathogens, agents belonging to family Anaplasmataceae (Order Rickettsiales) agents stand out due their worldwide distribution and zoonotic potential. In this review we aimed to review the genetic diversity of the tick-transmitted genera Ehrlichia, Anaplasma and "Candidatus Neoehrlichia sp." in wild carnivores Caniformia (Canidae, Mustelidae and Ursidae) and Feliformia (Felidae, Hyanidae, Procyonidae and Viverridae) worldwide, discussing the implications for human and domestic animal health and wildlife conservation. Red foxes (Vulpes vulpes) have been identified as hosts for Anaplasma spp. (A. phagocytophilum, Anaplasma ovis, A. platys), Ehrlichia canis and "Candidatus Neoehrlichia sp." (FU98 strain) and may contribute to the maintaenance of A. phagocytophilum in Europe. Raccoons (Procyon lotor) have been reported as hosts for E. canis, A. bovis, "Candidatus Neoehrlichia lotoris" and A. phagocytophilum, and play a role in the maintenance of A. phagocytophilum in the USA. Raccoon dogs (Nyctereutes procyonoides) may play a role as hosts for A. bovis and A. phagocytophilum. New Ehrlichia and/or Anaplasma genotypes circulate in wild canids and felids from South America and Africa. While Ehrlichia sp. closely related to E. canis has been reported in wild felids from Brazil and Japan, Anaplasma sp. closely related to A. phagocytophilum has been detected in wild felids from Brazil and Africa. Red foxes and mustelids (otters) are exposed to E. canis in countries located in the Mediaterranean basin, probably as a consequence of spillover from domestic dogs. Similarly, E. canis occurs in procyonids in North (raccoons in USA, Spain) and South (Nasua nasua in Brazil) Hemispheres, in areas where E. canis is frequent in dogs. While "Candidatus Neoehrlichia lotoris" seems to be a common and specific agent of raccoons in the USA, "Candidatus Neoehrlichia sp." (FU98 strain) seems to show a broader range of hosts, since it has been detected in red fox, golden jackal (Canis aureus) and badger (Meles meles) in Europe so far. Brown (Ursus arctos) and black (Ursus americanus) bears seem to play a role as hosts for A. phagocytophilum in the North Hemisphere. Anaplasma bovis has been detected in wild Procyonidae, Canidae and Felidae in Asia and Brazil. In order to assess the real identity of the involved agents, future works should benefit from the application of MLST (Multi Locus Sequence Typing), WGS (Whole Genome Sequencing) and NGS (Next Generation Sequencing) technologies aiming at shedding some light on the role of wild carnivores in the epidemiology of Anaplasmataceae agents.
RESUMO
This study aimed to screen wild rodents from southern Chile, for the presence of Anaplasmatacea. Spleen samples from 33 wild rodents trapped in Valdivia Province were screened by conventional PCR (cPCR), targeting the Anaplasmataceae 16S rRNA gene (16S). Positive samples were further evaluated, targeting a larger 16S fragment, groEL operon, and gltA gene, followed by sequencing and phylogenetic analysis. Anaplasmataceae DNA was detected in 15% (five of 33) of the tested rodents (Abrothrix sp. [four of five] and Mus musculus [one of five]). Analysis of sequenced products based on the 16S gene revealed high similarity with "Ca. Neoehrlichia mikurensis," "Ca. Neoehrlichia lotoris" and "Ca. Neoehrlichia arcana" (97.8%-98.6%). A lower similarity was observed with Candidatus Neoehrlichia groEL (89.7%-92%) and gltA (79.5%-79.9%) loci. According to the 16SrRNA, groEL and gltA phylogenetic analyses, two closely related genotypes of "Candidatus Neoehrlichia" spp. from Chile were observed, which clustered together in a separate clade from other species in this genus. This study suggests the presence of two genotypes of a novel species of "Candidatus Neoehrlichia," proposed as "Candidatus Neoehrlichia chilensis," circulating in rodents from Chile. This is the first report of "Ca. Neoehrlichia" species in rodents from America.