Amblyomma scalpturatum Neumann, 1906 (Acari: Ixodidae): confirmation in Acre State, Brazil, and description of parasitism in a human

Abstract

Amblyomma scalpturatum is a tick species that is unique to South America. It is commonly associated with the Amazon biome and has been reported in some Brazilian states. This tick species exhibits host specificity: it parasitizes tapirs and suidae. Its role in transmitting pathogens to humans is still unknown. Amblyomma scalpturatum is known to be a human-biting tick; however, there is only one report showing that humans make suitable hosts for this species. The knowledge of tick fauna is lacking in the Acre State. This study collected free-living ticks with the aim of finding new records in Acre State. Collections were carried out in Amazon forest fragments in Rio Branco municipality. An A. scalpturatum specimen was identified and submitted sequencing of the ITS-2 gene. This study presents the first molecular confirmation of A. scalpturatum collected in situ in Acre State, North Region, Brazil. This study also presents the first record of a successfully completed feeding by an A. scalpturatum nymph on a human host in the North region of Brazil. Further investigation is needed to ascertain the complete life cycle of this tick species, its seasonality in the environment, and its relationship to pathogens and competence to transmit them. ResumoAmblyomma scalpturatum é uma espécie de carrapato que ocorre apenas na América do Sul. Está comumente associada ao bioma da Amazônia e tem sido relatada em alguns estados brasileiros. Esta espécie de carrapato apresenta especificidade a hospedeiros: parasita antas e suídeos. Sua competência em transmitir agentes patogênicos a seres humanos é ainda desconhecida. Amblyomma scalpturatum é também conhecido por picar seres humanos; entretanto, há apenas um relato que evidencie que seres humanos sejam capazes de serem hospedeiros adequados. Ainda existem lacunas no conhecimento sobre a ixodofauna no estado do Acre. Neste estudo foram coletados carrapatos de vida livre com o objetivo de encontrar novos registros para o estado do Acre. Coletas de carrapatos foram realizadas em fragmentos de floresta Amazônica no município de Rio Branco. Um exemplar de A. scalpturatum foi identificado e submetido a sequenciamento do gene ITS-2. Este estudo apresenta a primeira confirmação molecular de A. scalpturatum coletado in situ no estado do Acre, região Norte, Brasil. Este estudo também apresenta o primeiro relato de parasitismo completo de uma ninfa de

New records of ticks (Acari: Ixodidae) infesting wild birds in a forest fragment in Acre, Brazilian Amazon

“…In that study, three genera of ticks were identified parasitizing the animals, totaling eight species: Amblyomma dubitatum Neumann, 1899, Amblyomma naponense Packard, 1869, Amblyomma humerale Koch, 1844, Amblyomma pacae Aragão, 1911, Amblyomma rotundatum Koch, 1844, Amblyomma varium Koch, 1844, R. microplus, and Dermacentor nitens Neumann, 1897. More recently, the presence of Amblyomma scalpturatum Neumann 1906, collected in situ, and its parasitism on a human host were confirmed in the state of Acre (Aguirre et al, 2019).…”

“…The genus Amblyomma is the most common in the Amazon Biome (Gianizella, Moraes, Nascimento, & Martins, 2018b). Ticks of this genus have already been observed parasitizing different groups of animals in the Amazon: wild birds (Ogrzewalska, Uezu, & Labruna, 2010;Martins, Fecchio, & Labruna, 2014;Lima et al, 2018), chelonians (Labruna, Camargo, Terrassini, Schumaker, & Camargo, 2002;Soares et al, 2015;Gianizella et al, 2018b), crocodilians (Labruna et al, 2005;Witter et al, 2016;Gianizella et al, 2018a), wild mammals (Martins et al, 2013;Soares et al, 2015), and even the human being (Aguirre et al, 2019).…”

“…There are few data and studies on the occurrence of these ectoparasites in the state of Acre (Lima et al, 2018;Aguirre et al, 2019;Gruhn et al, 2019). The first reference about the presence of ticks in Acre was made by Aragão (1936), who reported the occurrence of Amblyomma incisum Neumann, 1906, Amblyomma ovale Koch, 1844, and Rhipicephalus microplus (Canestrini, 1888 in animals in the then territory of Acre.…”

Ticks from the Brazilian Amazon: Species, Distribution and Host-Relations

“…Human parasitism by the nymphal and adult stages of this species has been reported in the states of Mato Grosso (municipality of Jauru) and Rondônia (municipality not precisely indicated), however in this latter state it was not specified whether these adult ticks were fixed or walking on humans [38,93]. The nymphal stage was also collected from a human who was probably infested with this tick in the municipality of Porto Velho in the state of Rondônia [115]. The nymph and adult stages of this species were also found parasitizing humans in the state of Amazonas, in the municipalities of Coari, Fonte Boa, Jutaí, Presidente Figueiredo and Santa Isabel Rio Negro [31,107].…”

First report of Amblyomma latepunctatum and the second record of Ixodes luciae in the state of Acre, Brazil

“…As so, A. incisum had only been reported once, by Aragão (1936), through examining the material in the Ixodid Collection of the Oswaldo Cruz Institute. About A. scalpturatum was confirmed by Aguirre et al (2019) through morphological and molecular analyses (subjected to sequencing of the ITS2 gene). Now, through the present study, occurrence of the species A. latepunctatum in the state of Acre has been confirmed.…”