Participation o ticks in the infectious cycle f canine visceral leishmaniasiss, in teresina, piauí,BBrazil / Participação do Rhipicephalus sanguineus no ciclo infeccioso da leishmaniose visceral canina em Teresina, Piauí, Brasil

In this study, we detected Leishmania spp. infection in R. sanguineus collected from dogs that were naturally infected with L. (L.) infantum. We examined 35 dogs of both sexes and unknown ages. The infected dogs were serologically positive by the immunofluorescence antibody test (IFAT), enzyme-linked immunosorbent assay (ELISA), and Quick Test-DPP (Dual Path Platform), as well as parasitological examination of a positive skin biopsy or sternal bone marrow aspiration. Ten negative dogs were included as controls. The ticks that infested these dogs were collected in pools of 10 adult females per animal. The PCR was performed with specific primers for Leishmania spp., which amplified a 720-bp fragment. Of the 35 analyzed samples, a product was observed in eight samples (8/35; 22.9%). We conclude that the presence of parasite DNA suggests that ticks participate in the zoonotic cycle of canine visceral leishmaniasis, in the city of Teresina, Piauí.

Neste estudo foi detectada infecção por Leishmania spp. em Rhipicephalus sanguineus (R. sanguineus) de cães naturalmente infectados por Leishmania (Leishmania) infantum = L. (L.) infantum. Foram utilizados 35 cães de ambos os sexos e idades desconhecidas, sorologicamente positivos pelas técnicas de reação de imunofluorescência indireta (RIFI), enzyme-linked immunosorbent assay (ELISA) e Quick Test-DPP (Dual Path Plataform), e com exame parasitológico positivo em biópsia de pele ou punção de medula óssea esternal e 10 cães domiciliados negativos, como controle. Os carrapatos que infestavam esses cães foram coletados em pool de 10 fêmeas adultas por animal. A Reação em Cadeia pela Polimerase (PCR = Polymerase Chain Reaction) foi realizada com primers para Leishmania spp., que amplificaram 720pb. O resultado das 35 amostras processadas revelou a amplificação de oito amostras (8/35 - 22,9%). Conclui-se que a presença do DNA do parasita sugere que carrapatos podem estar participando do ciclo zoonótico da leishmaniose visceral canina na cidade de Teresina, Piauí.

Estudo da infecção e morbidade da doença de Chagas no municÝpio de João Costa: Parque Nacional Serra da Capivara, Piauí, Brasil / Study of the infection and morbidity of Chagas' disease in municipality of JoÒo Costa: National Park Serra da Capivara, Piauí, Brazil

In order to investigate aspects of the infection and morbidity of Chagas' disease in the municipality of JoÒo Costa, PiauÝ State, Brazil, we carried out a serological survey to detect anti-Trypanosoma cruzi antibodies in 2,080 individuals, by indirect immunofluorescence, indirect hemagglutination and ELISA. A total of 189 seropositive and 141 seronegative patients were evaluated by anamnesis, physical exam and electrocardiogram (EKG). The parasitaemia of 106 chagasic patients was evaluated by indirect xenodiagnosis and PCR (polymerase chain reaction). The total seropositivity was 9.8, with intervals of 0.5 in patients younger than 10 years old, and 39.4 among patients older than 59 years old, independently of the sex. The PCR and xenodiagnosis were positive, respectively in 74.5 and 15.1 of the seropositive patients (p < 0.05). The rate of abnormal EKG was 41.3 in chagasic and 15.6 in non-chagasic patients (p < 0.05). In spite of the high prevalence of infection in the investigated population, the low rate of seropositivity among children is indicative of a possible decrease of the active transmission mediated by triatomines. The high proportion of the chagasic component on the cardiopathy prevalence is indicative of the high morbidity of Chagas' disease in the studied region.