Detección molecular de Anaplasmataceae en cánidos domésticos y silvestres de distintas biorregiones de Chile

SOPHIA DI CATALDO; CLAUDIA ULLOA-CONTRERAS; AITOR CEVIDANES; SACRISTÁN, IRENE; CARLA BARRÍA; GERARDO ACOSTA-JAMETT; DIEGO PEÑALOZA-MADRID; SALLABERRY-PINCHEIRA, NICOLE; JAVIER MILLÁN

Mexicali

Congreso; VII Congreso Latinoamericano de enfermedades rickettsiales; 2019

Universidad Autónoma de Baja California

IntroductionThe Anaplasmataceae family is composed by obligatory intracellular organisms that parasitize different types of host cells, including the genus Ehrlichia and Anaplasma (1). In Chile, there is limited information about their presence in dogs (2), and no published information exists regarding free-livings wild canids. ObjectiveTo investigate the occurrence of Anaplasmataceae in rural dogs and foxes from six different bioclimatic regions of Chile. MethodsStudied regions were: Coastal Desert (CD), Mountain Desert (MD), Steppe (S), Mediterranean (M), Temperate Warm Rainy (TWR), and Temperate Maritime Rainy (TMR). Blood and ectoparasite samples from 1072 rural dogs, 163 Andean (Lycalopex culpaeus) and 97 South American gray (L. griseus) foxes were analyzed for the presence of DNA of Anaplasmataceae by conventional PCR targeting the 16S rRNA gene (3), and the amplicons were sequenced. In the region MD only dogs were sampled.ResultsObserved prevalence in dogs was 11.4%. The highest prevalence was observed in the M region (39.5%), while no positive animals were found in regions MD and TMR. In foxes, overall prevalence was 7.7%: 5.6% in Andean (in CD and M regions) and 11% in gray fox (in S and TWR regions). All the obtained sequences showed the highest identity with published sequences of A. platys. Rhipicephalus sanguineus and Amblyomma spp. ticks were retrieved from dogs and foxes of most regions except in MD and TMR.Discussion:This study confirms the widespread presence of the etiological agent of the Infectious Canine Cyclic Thrombocytopenia in Chile, including in the northern regions were the tropical lineage of R. sanguineus is present (4,5). No positive animals were found in regions were the tick is supposed to be absent. In addition, the highest prevalence detected in the M region was coincident with the more adequate conditions for R. sanguineus (6,7). We showed by the first time that free-living foxes are infected by the bacterium in Chile. Though further molecular characterization is needed, interspecific dog-fox transmission might be taking place.Conclusion:In view of the obtained results, risk factors analysis of Anaplasmataceae infection, including intrinsic (age, sex) and extrinsic (region, season, tick infestation) factors will provide tools for better understanding the dynamic of infection in dogs and foxes.