Detection of Rickettsia tamurae-like and other spotted fever group rickettsiae in ticks (Acari: Ixodidae) associated with wild birds in the Western Amazon, Brazil

Ticks are vectors for several pathogens, including bacteria belonging to the Rickettsia genus, such as Rickettsia rickettsii and Rickettsia parkeri, the causative agents of spotted fever. The aim of the present study was to investigate the tick species richness and rickettsial agents associated with wild birds captured in the Humaita Forest Reserve, Acre, in the Western Amazon region. Wild birds were captured with ornithological nets for visual inspection with the purpose of collecting ticks, which were identified through morphological analyses and molecular tests for several genes (12S rDNA, 16S rDNA, gltA, ompA, and sca4). A total of 607 wild birds were captured, 12% of which were parasitized by 268 ticks of the Amblyomma genus, with new host-parasite associations reported for Amblyomma calcaratum, Amblyomma geayi, Amblyomma longirostre, Amblyomma naponense, Amblyomma nodosum, and Amblyomma varium. Of the total ticks collected, 113 were tested for the presence of rickettsial DNA fragments, with 19 testing positive for R. parkeri in A. geayi, Rickettsia tamurae-like in Amblyomma sp., and Rickettsia amblyommatis in A. geayi, A. longirostre, and Amblyomma sp. We detected R. tamurae-like in Amblyomma larvae for the first time in the Western Brazilian Amazon biome, and registered spotted fever group rickettsiae, although the relevance of the detected species in a public health context should be further explored in South America, as well as new host-parasite interactions in this underexplored region.

Human parasitism and toxicosis by Ornithodoros rietcorreai (Acari: Argasidae) in an urban area of Northeastern Brazil

The soft tick, Ornithodoros rietcorreai, is a parasite of the rodent, Kerodon rupestris, and, to a lesser extent, of bats living in rock cavities in Northeastern Brazil. This report describes the first recorded episodes of human parasitism by this argasid tick, reported to the Brazilian Ministry of Health in September 2017. We assessed outdoor environments, roofs, animal nests and chicken coops in five houses located in an urban area of Russas City, Ceará State, Brazil. Our results confirmed the presence of the tick in two of the assessed houses. The collected specimens were molecularly identified as O. rietcorreai. Of the ten individuals living in the investigated properties, three reported being parasitized by ticks. Although O. rietcorreai ticks were recovered from the evaluated houses, the primary hosts for the ticks were not identified. The retrospective medical records of parasitized individuals reported the following: local pruritus 3/3, malaise 3/3, local edema and erythema 3/3, local rash 3/3, local pain 3/3, slow lesion healing 3/3 and paresthesia 1/3. One of the individuals reported four parasitism episodes (March, June, July and August 2017) and required medical attention and the administration of anti-allergy and anti-inflammatory drugs. The aforementioned reports were the first to address human parasitism, with subsequent toxicosis, by this tick species in Brazilian urban areas. Attention was drawn to the potential consequences of such episodes to the health of previously exposed individuals.

[Mutagenic occurrence in teleoginae of Rhipicephalus sanguineus from intradomiciliary environment at Rio de Janeiro city]

From material collected by into a residence house at Rio de Janeiro city, using an aspirator machine during four continues hours in all house, it was captured 1,284 Rhipicephalus sanguineus including 289 females; one of them showed a mutagenic alteration like an asymmetry of opistosome, and monstrosity like a two anus. The first register of this phenomenon in R. sanguineus is reported.