RESUMEN
The genus Hepatozoon Miller (1908) contains a wide range of obligate parasitic organisms with complex life cycles involving vertebrates and hematophagous invertebrates. Despite over 300 species being described, only a small percentage has been characterized in snakes using morphological and molecular techniques. The prevalence of these parasites in snakes is significant, highlighting the need for molecular descriptions in such elusive hosts. Thus, the objective of this study was to determine molecularly the presence of Hepatozoon species in snakes from the Northeastern region of Argentina. Thirty-two specimens of eight snake species (Bothrops alternatus, Dryophylax hypoconia, Erythrolamprus jaegeri coralliventris, Erythrolamprus poecilogyrus, Erythrolamprus semiaureus, Philodryas olfersii latirostris, Pseudablabes (ex Philodryas) patagoniensis and Palusophis (ex Mastigodryas) bifossatus were collected and examined. PCR analysis of the 18S rRNA locus detected four samples (12% prevalence) positive for the presence of Hepatozoon DNA. Phylogenetic analysis positioned the 18S rRNA Hepatozoon sequences obtained in three different clades, one with Hepatozoon musa, another with sequences of Hepatozoon cuestensis, while the third was placed as a sister taxon to a clade including Hepatozoon cevapii and Hepatozoon massardi. This study presents the first documentation of Hepatozoon infecting snakes in Argentina, thereby expanding their distribution within southern South America. Additionally, B. alternatus and Pa. bifossatus are reported as new hosts of Hepatozoon.
Asunto(s)
ADN Protozoario , Eucoccidiida , Filogenia , ARN Ribosómico 18S , Serpientes , Animales , Argentina , Serpientes/parasitología , ARN Ribosómico 18S/genética , Eucoccidiida/genética , Eucoccidiida/aislamiento & purificación , Eucoccidiida/clasificación , ADN Protozoario/genética , Coccidiosis/parasitología , Coccidiosis/veterinaria , Coccidiosis/epidemiología , Análisis de Secuencia de ADN , ADN Ribosómico/genética , Prevalencia , Reacción en Cadena de la PolimerasaRESUMEN
The current work assessed the infection with Ehrlichia and Anaplasma species, and exposure to Rickettsia spp. in free-ranging capybaras in the Iberá wetlands ecoregion in Argentina. By indirect immunofluorescence assay, 37 out of 51 (73%) capybara sera were seropositive to Rickettsia spp., with 23.5% and 4% samples considered homologous to Rickettsia parkeri and Rickettsia bellii, respectively (or very closely related serotypes). Anaplasmataceae DNA was found to be highly prevalent in capybaras, with 33 out of 62 samples positive for Anaplasma sp. with Ct values of 28.64 ± 0.35 (average ± standard error), and 12 samples positive for Ehrlichia sp. with Ct values of 31.74 ± 0.87. Anaplasma sp. from capybaras was closely related to Anaplasma sp. reported to infect Amblyomma dubitatum in Iberá wetlands and to Anaplasma odocoilei, while the detected Ehrlichia sp. was closely related to "Candidatus Ehrlichia hydrochoerus" previously reported to infect capybaras in Brazil and A. dubitatum in Iberá wetlands. Structures compatible with Anaplasma morulae were observed in the cytoplasm of platelets from Anaplasma-positive capybaras. Our findings show that capybaras from the Iberá wetlands were exposed to Rickettsia species related to R. bellii and to the pathogen R. parkeri, and were infected with "Ca. Ehrlichia hydrochoerus" and a novel Anaplasma species, herein named "Candidatus Anaplasma capybara".
Asunto(s)
Rickettsiaceae , Roedores , Animales , Humedales , Argentina , BrasilRESUMEN
Bacteria of the sister genera Ehrlichia and Anaplasma (Anaplasmataceae) are obligate intracellular Alphaproteobacteria that are transmitted mostly through arthropod vectors. These agents can infect different vertebrate cells, depending on the species involved, and can cause diseases in animals and humans. In this study, we evaluated the presence of Anaplasmataceae bacteria in Amblyomma calcaratum ticks collected from a road-killed Tamandua tetradactyla in the Rainforest ecoregion in Argentina. All samples were screened for Anaplasmataceae DNA using a real-time PCR assay targeting the 16S rRNA gene. Evidence of Anaplasmataceae DNA was detected in three out of thirty-nine Am. calcaratum ticks. Phylogenetic analysis of a portion of 16S rRNA gene positioned one sample (Ehrlichia sp. strain Ac124) with Ehrlichia sequences and the other two samples with Anaplasma sequences; Anaplasma sp. strain Ac145 close to Anaplasma odocoilei and Anaplasma sp. strain Ac152 in an ancestral position to most Anaplasma species. The groEL sequence obtained showed that Ehrlichia sp. strain Ac124 was phylogenetically related to Ehrlichia sp. strain Iberá reported infecting Amblyomma tigrinum from Iberá wetlands in Argentina. Phylogenetic analysis using the rpoB sequence positioned Anaplasma sp. strain Ac145 close to the canine pathogen Anaplasma platys, while Anaplasma sp. strain Ac152 was positioned close to the bovine pathogen Anaplasma marginale. In this study, three Anaplasmataceae agents were detected in adults of Am. calcaratum associated with a T. tetradactyla. These results suggest that the number of Anaplasmataceae species, as well as their distribution, is largely unknown.