Ocorrência de carrapato do complexo Amblyomma maculatum (Acari: Ixodidae) e sua relação com Rickettsia na Baixada Maranhense, maranhão, Brasil

Abstract

In 2013 it was reported for the first time in the State of Maranhão ticks of the Amblyomma maculatum complex, in the meso-region of Baixada Maranhense. Until then, the life cycle of these ectoparasites in the region, as well as the related hosts, remained unknown. All stages of life of this tick species can transmit bacteria of the genus Rickettsia, including those belonging to the spotted fever group (SFG), one of the most important diseases transmitted by ticks, that has as its main vector, ticks of the Amblyomma genus. The aim of this study was report the occurrence of the life stages of these ticks in Baixada Maranhense, its hosts and its relation with Rickettsia. The objective was to report the occurrence of life stages of Amblyomma maculatum sensu lato ticks in the Baixada Maranhense, its hosts and its relationship with Rickettsia. From October 2017 to September 2018 five campaigns were carried out in the municipality of Bacurituba, Maranhão state, located in the Baixada Maranhense, with an interval of three months between them. Through traps and manual containment, serum samples and ticks were collected from small non-flying wild mammals and domestic mammals; birds were trapped using mist nets and inspected for tick infestation research. The serum samples were tested for the following species of Rickettsia: Rickettsia rickettsii cepa Taiaçu, Rickettsia parkeri cepa At24, Rickettsia amblyommatis cepa Ac37, Rickettsia rhipicephali cepa HJ5 e Rickettsia bellii cepa Mogi, by indirect immunofluorescence assay (IFA). Durant all expeditions the dragging of flannels were performed. Dogs, horses, pigs and cattle were parasitized by adult forms of A. maculatum s. l. ticks. Birds of the species Ammodramus humeralis presented parasitism by immature forms of A. maculatum s. l. Adult and immature forms of A. maculatum s. l. were collected in four of the five campaigns. Molecular tests for detection of Rickettsia in specimens A. maculatum s. l. were negative. Dogs, horses, pigs and a rodent of the genus Rattus sororeagiram (≥64) for at least one species of Rickettsia, with titers ranging from 64 to ≥ 4096. Buff and buffalo samples were negative. This research records for the first time the occurrence of adult stages of the A. maculatum s. l. tick in dogs, pigs and cattle, and immature forms in birds, thus increasing the range of hosts of this tick in the region, where before there was only reported parasitism in horses.