Prevalence of Anaplasmataceae in rural dogs and wild foxes from different bioclimatic regions of Chile

SOPHIA DI CATALDO; AITOR CEVIDANES; BERNARDITA JULIO-KALAJZIC; SACRISTÁN, IRENE; NAPOLITANO, CONSTANZA; CABELLO, JAVIER; DANIEL GONZÁLEZ-ACUÑA; SALLABERRY-PINCHEIRA, NICOLE; PABLO LILLO; JULIANA VIANNA; HIDALGO-HERMOSO, EZEQUIEL; JAVIER MILLÁN

Medellín

Congreso; VI Congreso Latinoamericano de Enfermedades Rickettsiales & I Encuentro de ecología y control de ectoparásitos; 2017

Universidad de Antioquia

Introduction: the family Anaplasmataceae is composed of obligatory intracellular organisms that parasitize different types of host cells, including the genus Ehrlichia and Anaplasma. In Chile, there is limited information about their presence in dogs, and no information exists regarding free-livings wild canids. Objects: our aim was to investigate the occurrence of Anaplasmataceae in rural dogs and foxes from five different bioclimatic regions of Chile: Northern (N, arid-semiarid), Central (C, Mediterranean), Central-South (CS, temperate-dry), Southern (S, temperate-rainy) and Easter Island (EI, tropical rainforest). Methods: samples from 232 dogs, 55 culpeo (Lycalopex culpaeus) and 30 gray (L. griseus) foxes were analyzed for the presence of DNA of Anaplasmataceae by conventional PCR targeting the 16S rRNA gene and the amplicons were sequenced. Results: observed prevalence in dogs was 9.5%. The highest prevalence was observed in region C (42.2%), being significantly higher than in regions CS (2.1%), S (0%), and EI (4%). In foxes, overall prevalence was 8.4%: 5.7% in culpeo (6% both in the regions N and C) and 3.3% in gray fox (only detected in the region S: 20%). The prevalence in dogs and foxes from the region C was significantly different. Conclusions: all the obtained sequences showed the highest identity with published sequences of A. platys. This study confirms that this is the main agent of canine ehrlichiosis in Chile, the etiological agent of the Infectious Canine Cyclic Thrombocytopenia. Its way of transmission is unclear, but Rhipicephalus sanguineus is believed to be its vector. This is the first report of A. platys in American wild canids and the second worldwide. The highest prevalence observed in temperate regions probably resembles the distribution of the vector. The detection of an infected fox from the S region deserves further investigation. Though further molecular characterization is needed, interspecific dog-fox transmission might be taking place.