First record of Rickettsia bellii in Amblyomma varium and Amblyomma goeldii from the Eastern Amazon

Abstract

Abstract This study investigated the presence of Rickettsia spp., Ehrlichia spp., Anaplasma spp., and Borrelia spp. DNA in questing ticks collected from a forest fragment under constant anthropogenic pressure in the state of Pará, Brazil. The fragment was divided into three zones: interior, edge, and surrounding matrix. Ticks were collected in all zones using flannel drag sampling, flannel leggings, and CO2-baited traps. Nymphs and adults were morphologically identified using taxonomic keys, while larvae were subjected to molecular identification. DNA extracted from the ticks was tested for the target pathogens using polymerase chain reaction (PCR). In total, 561 questing ticks (525 larvae, 29 nymphs, and 7 adults) were collected, representing eight species: Amblyomma cajennense sensu stricto, Amblyomma calcaratum, Amblyomma geayi, Amblyomma goeldii, Amblyomma humerale, Amblyomma naponense, Amblyomma pacae, and Amblyomma varium. Rickettsia bellii was detected in one A. varium larva and one A. goeldii larva. All samples tested negative for Ehrlichia spp., Anaplasma spp., and Borrelia spp. This is the first report of R. bellii in A. varium and A. goeldii in Brazil.

Keywords

• Etiological agents
• ticks
• Amazon rainforest
• Brazil