Ixodes tropicalis (Acari: Ixodidae) infesting a human and molecular detection of Rickettsia bellii, Colombia

Abstract

Introduction: Ixodes tropicalis is a little-known tick species reported parasitizing wild rodents only in Colombia and Perú. Objective: To report a case of I. tropicalis infesting a human in the south of the metropolitan area of the Valle de Aburrá, Antioquia, Colombia, and to report the molecular detection of Rickettsia bellii in this species. Materials and methods: The tick was identified using a morphological key and sequencing of tick mitochondrial 16S rRNA. Additionally, bacterial and protozoa pathogens were evaluated using PCR for the detection of Rickettsia spp., family Anaplasmataceae, Borrelia spp., and piroplasmid. Results: We identified the tick as an I. tropicalis female according to Kohls, 1956, description and to partial 16S rRNA sequences showing a minimum of 5% divergencies compared to Ixodes sequences. We also detected the gltA gene of R. bellii in the tick with 99.87% of identity. Conclusion: This is the first report in Colombia of a species of the Ixodes genus parasitizing a human and the first report of the detection of R. bellii in this tick species.

Keywords

• ixodes
• rickettsia
• bacteria
• disease vectors