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

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.Com 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

Redescription of <i>Haemaphysalis (Rhipistoma) elliptica</i> (Koch, 1844), an old taxon of the <i>Haemaphysalis (Rhipistoma) leachi</i> group from East and southern Africa, and of <i>Haemaphysalis (Rhipistoma) leachi</i> (Audouin, 1826) (Ixodida, Ixodidae

Koch (1844) originally described only the male of Haemaphysalis (Rhipistoma) elliptica (Koch, 1844), which he named Rhipistoma ellipticum. For the past century, however, this name has been considered a junior synonym of Haemaphysalis (Rhipistoma) leachi (Audouin, 1826), or a nomen nudum. We redescribe here the male and larva of H. (R.) elliptica and describe the female and nymph for the first time. Our redescription is based on the male holotype, plus numerous specimens from southern and East Africa. The adults of this tick parasitize domestic and wild carnivores, and the immature stages infest rodents in these regions. For comparative purposes redescriptions of all parasitic stages of H. (R.) leachi are provided. It parasitizes the same hosts as H. (R.) elliptica in Egypt, and in northeastern, Central, West and East Africa

Redescription of Haemaphysalis (Rhipistoma) elliptica (Koch, 1844), an old taxon of the Haemaphysalis (Rhipistoma) leachi group from East and southern Africa, and of Haemaphysalis (Rhipistoma) leachi (Audouin, 1826) (Ixodida, Ixodidae)

Koch (1844) originally described only the male of Haemaphysalis (Rhipistoma) elliptica (Koch, 1844), which he named Rhipistoma ellipticum. For the past century, however, this name has been considered a junior synonym of Haemaphysalis (Rhipistoma) leachi (Audouin, 1826), or a nomen nudum. We redescribe here the male and larva of H. (R.) elliptica and describe the female and nymph for the first time. Our redescription is based on the male holotype, plus numerous specimens from southern and East Africa. The adults of this tick parasitize domestic and wild carnivores, and the immature stages infest rodents in these regions. For comparative purposes redescriptions of all parasitic stages of H. (R.) leachi are provided. It parasitizes the same hosts as H. (R.) elliptica in Egypt, and in northeastern, Central, West and East Africa

Transmission expérimentale du virus de la fièvre hémorragique de Crimée-Congo : place de trois espèces vectrices dans les cycles de maintenance et de transmission au Sénégal

Dans cet article, nous rapportons la place de trois espèces de tiques Amblyomma variegatum (Fabricius, 1794), Hyalomma marginatum rufipes (Koch, 1844) et Hyalomma truncatum (Koch, 1844) dans les cycles de maintenance et de transmission du virus de la fièvre hémorragique de Crimée-Congo (CCHF) au Sénégal. Les imagos de ces espèces ont été infectés par inoculation intra-coelomique. La réplication du virus, les transmissions verticale (transovarienne et transtasiale) et horizontale pour les différentes stases ont été étudiées par les techniques d'isolement sur souriceaux nouveau-nés, d'immunofluorescence indirecte, par la réaction de polymérisation en chaine et par ELISA.Les résultats obtenus ont montré que 15 jours après l'inoculation, des taux d'infection de 100 % ont été obtenus avec Hyalomma marginatum rufipes et Hyalomma truncatum. Ce taux passe à 60 % chez Amblyomma variegatum. Les imagos des trois espèces infectées ont transmis le virus à leurs hôtes ou cours du repas sanguin (100 %). Une transmission transovarienne élevée pour les espèces Hyalomma marginatum rufipes et Hyalomma truncatum a été observée avec respectivement 53 et 50 % de larves positives en immunofluorescence indirecte. Ce taux passe à 12 % chez Amblyomma variegatum. L'infection des tiques ne persiste pas au-delà de la première génération chez les trois espèces étudiées. Les tiques sont donc des vecteurs-réservoirs temporaires mais pas des réservoirs permanents du virus CCHF

Contribution to the knowledge of ticks (Acarina: Ixodidae) in Gabon

International audienceFew data are available on the distribution of tick species in Gabon. We report the results of a survey of ticks collected from wild and domestic animals, and in the environment, in several regions of Gabon. We identified four tick species for the first time in Gabon, namely Haemaphysalis paralaechi, Ixodes aulacodi, Rhipicephalus annulatus and Rhipicephalus simpsoni and we report 28 tick species for this countr

A note on Hyalomma nitidum, its distribution and its hosts

The paper summarises the morphological characteristics, the known geographical dis- tribution and hosts of Hyalomma nitidum, a tick which has never been properly characterised. H. nitidum was first described in Cameroon in 1919, long considered as a synonym of Hyalomma truncatum and recognised as a separate and valid species only since the early 1970s. H. nitidum occurs from Senegal to the Central African Republic in more humid conditions than H. truncatum, roughly to the south of the isohyet of 900 mm. Adults are parasitic on various wild and domestic ungulates, on which immatures have not been found. Nymphs, identified after moulting to adults, have been found on a hare, and tentatively identified larvae and nymphs of this species have also been collected on hare as well as on a zebra mouse. The tick has been found infected with the virus of Crimean-Congo haemorrhagic fever, so far no other disease associations are known

Rhipicephalus sanguineus Latreille 1806

Rhipicephalus sanguineus Latreille, 1806 This common species is mainly associated with domestic dogs. It has been collected in Libreville on dogs (Morel and Vassiliades, 1963; Moubamba, 2006). We also found it, at all stages, on domestic dogs in Franceville. Rhipicephalus simpsoni Nuttall, 1910 We found adult R. simpsoni, for the first time in Gabon, on the greater cane rat Thryonomys swinderianus in Bighoundou.Published as part of Pourrut, X., Emane, K. A., Camicas, J. - L., Leroy, E. & Gonzalez, J. P., 2011, Contribution To The Knowledge Of Ticks (Acarina: Ixodidae) In Gabon, pp. 465-471 in Acarologia 51 (4) on page 469, DOI: 10.1051/acarologia/20112028, http://zenodo.org/record/539880