Occurrence of ticks (Acari: Ixodidae) on human hosts, in three municipalities in the State of Pará, Brazil

Abstract

Assuming the existence of tick parasitism in humans in the State of Pará, an aggregate observational study was developed along a transversal line in three cities of the State, during two years. Interviews and examinations of 2,160 townspeople and tourists were carried out, without discrimination of ethnic, sex, age, or social status, and classified for effects analyzed for four bands of age, six types of activities in the society, and two sexes. Larvae, nymphs, and adults of ticks had been identified with cases of parasitism involving six species, of the genus Amblyomma, the genus Ixodes, Rhipicephalus sanguineus, Anocentor nitens, and Ornithodorus talaje (the first case registered in Pará), infecting human beings. Adults and agricultural workers were most frequently attacked, followed by students. A. cajennense and R. sanguineus are the species most frequent in the parasitism affecting humans, and A. cajennense is the dominant species. The statistical prevalence was largest in Cachoeira do Arari, Ilha do Marajó. In Santarém the greatest average intensity of parasitism was for R. sanguineus, and in the other locations it wasfor A. cajennense. Agricultural workers faced the greatest risk from parasitism, and to place in practice elementary measures of prevention would reduce by 25% the number of cases.Keywords: Ixodidae on human beings, Cachoeira do Arari, Marajó Island, Santarém, Paragominas city. ResumoCom a hipótese de parasitismo por carrapatos em humanos no Estado do Pará, foi desenvolvido estudo observacional, agregado, transversal em três mesoregiões do Estado, durante dois anos. Foram entrevistados e examinados 2.160 munícipes, e turistas, sem discriminação étnica, de sexo, idade, e social, classificados para efeito de análises em quatro faixas de idade, seis tipos de atividades na sociedade, e dois sexos. Houve casos de parasitismo por larvas, ninfas, e adultos de carrapatos, envolvendo seis espécies do gênero Amblyomma, o gênero Ixodes, Rhipicephalus sanguineus, Anocentor nitens e Ornithodorus talaje (primeiro registo para o Estado). Adultos e os trabalhadores rurais são os mais atacados, seguidos dos estudantes. A. cajennense e R. sanguineus são as espécies mais freqüentes no parasitismo de humano, e A. cajennense é a espécie dominante. A prevalência foi superior a 40% nos três municípios, e estatisticamente maior em Cachoeira do Arari, Ilha de Marajó. Em Santarém R. sanguineus teve a maior intensidade média de parasitismo, nos outros municípios foi por A. cajennense. Estar em atividade rural dobra o risco do parasitismo, e o esclarecimento da população, para colocar em prática medidas elementares de prevenção reduziria em 25% o número de casos.Palavras-chave: Ixodidae em seres humanos, Cachoeira do Arari, Ilha de Marajó, Santarém, município de Paragominas.

Serosurvey for tick-borne diseases in dogs from the Eastern Amazon, Brazil

“…Due to this lack of information about canine babesiosis in the Brazilian Amazon region, the occurrence of positive dogs to B. canis vogeli (42.6%) can only be compared to other Brazilian studies, in which the prevalence of antibodies against this parasite in sera from dogs varied from 35.7% in Paraná state (TRAPP et al, 2006) to 66.9% in Minas Gerais state (RIBEIRO et al, 1990). We can infer from our results that the higher seroprevalence to B. canis vogeli observed among urban dogs is probably due to the predominating tick species recently found in the urban area of the municipality of Santarém, namely, R. sanguineus (SERRA-FREIRE, 2010), which is the only known vector of B. canis vogeli (DANTAS-TORRES, 2008).…”

Survey of canine tick-borne diseases in Lábrea, Brazilian Amazon: ‘accidental’ findings of Dirofilaria immitis infection

“…The populations of R. sanguineus s.l. have been considered to be widespread all over Brazil, including different urban areas of the Amazon region SERRA-FREIRE, 2010). For this reason, the current situation of Lábrea should be considered an exception for the occurrence of R. sanguineus, and consequently, for the tick-borne agents E. canis, A. platys, and B. vogeli.…”

HUMAN PARASITISM BY Rhipicephalus sanguineus sensu lato (ACARI: IXODIDAE) IN MATO GROSSO DO SUL, WEST-CENTRAL BRAZIL

“…While human parasitism by R. sanguineus s.l. is not common in Brazil, a few confirmed cases have been reported in the states of Pernambuco, Goiás, Rio de Janeiro, Pará, and Rio Grande do Sul (DANTAS-TORRES et al, 2006;LOULY et al, 2006;SERRA-FREIRE, 2010;SERRA-FREIRE et al, 2011;MENTZ et al, 2016). Extending previous information, the objective of this study was to | 97 report the finding of a R. sanguineus s. l. parasitizing a human in Campo Grande, State of Mato Grosso do Sul, Brazil.…”