Two novel Ehrlichia strains detected in Amblyomma tigrinum ticks associated to dogs in peri-urban areas of Argentina

CICUTTIN, GABRIEL L.; DE SALVO, M. NAZARENA; NAVA, SANTIAGO

COMPARATIVE IMMUNOLOGY MICROBIOLOGY AND INFECTIOUS DISEASES

ELSEVIER SCI LTD

Año: 2017 vol. 53 p. 40 - 44

0147-9571

The aim of this work was to describe two novel strains of Ehrlichia associated to Amblyomma tigrinum fromArgentina. Molecular detection of agents belonging to the family Anaplasmataceae was performed targetingthree different loci: 16S rRNA gene, dsb gene and a fragment of groESL heat shock operon. The results haveshown that two different strains of Ehrlichia sp. associated to A. tigrinum are circulating in peri-urban areas ofArgentina. The Ehrlichia strain detected in ticks from San Luis Province, named as Ehrlichia sp. strain San Luis, isclosely related to the Ehrlichia chaffeensis. The novel Ehrlichia strain detected in Córdoba Province, named asEhrlichia sp. strain Córdoba, is phylogenetically related to three Ehrlichia strains from Brazil, two of them isolatedfrom wild carnivorous and the third one isolated from horse. Even though Ehrlichia sp. strain Córdoba wasclustered with the three Ehrlichia strains from Brazil, the genetic similarity was too low to consider them as thesame taxonomic entity. Blood samples of dogs were positive to Anaplasma platys. The association of these twonovel strains with A. tigrinum has epidemiological relevance because adult stages of this tick species are commonparasite of dogs in rural and peri-urban areas and they are aggressive to humans. The presence of these two novelEhrlichia strains implies a potential epidemiological risk in Argentina because the species of the genus Ehrlichiaare known to be pathogenic to both domestic mammals and humans.