Occurrence of triatomines (Hemiptera: Reduviidae) in domestic and natural environments in Novo Remanso, Itacoatiara, Amazonas, Brazil

Abstract INTRODUCTION The present study reports the presence of triatomines in natural, peridomestic, and intradomicile environments in Itacoatiara municipality, state of Amazonas, a non-endemic region for Chagas disease. METHODS Active search was performed inside tree trunks, and palm trees, residences, and peridomiciles localized near the forest area. RESULTS: Twenty adults and ten triatomines nymphs were collected, fifteen of which were from natural forests, thirteen from intradomiciles, and two from peridomicile areas. CONCLUSIONS: The new records of adults and nymphs of triatomines in the intra- and peridomiciles suggest the adoption of prophylactic measures for vector surveillance in the study area.

Ecoepidemiology and biology of Eratyrus mucronatus Stål, 1859 (Hemiptera: Reduviidae: Triatominae), a sylvatic vector of Chagas disease in the Brazilian Amazon

Introduction Eratyrus mucronatus Stål, 1859 is a wild triatomine vector of Trypanosoma cruzi Chagas, 1909. However, little is known regarding the biology and ecoepidemiology of this triatomine in the Brazilian Amazon. The present study describes the biology of E. mucronatus grown under laboratory conditions and the epidemiological aspects of its natural breeding sites. Methods Five colonies were monitored in the field for 3 years. Temperature and humidity measurements were taken in the mornings and afternoons at the natural breeding sites, and the behavior and distribution of the nymphs and adults were observed in the wild colony. We also monitored the life cycle under controlled laboratory conditions. Results Some factors that were considered decisive for the establishment of these colonies were present at all of the colonies studied in the field. These factors included an active termite nest, a vertebrate for repast, and dry and shaded substrates with temperatures of 24-28°C and with humidity of 80-90%. A generation was developed in 274 days under these microclimatic conditions in the laboratory. Conclusions The climatic variables described in the field indicate that these environmental parameters have a limiting effect on the dispersal and colonization of E. mucronatus to new environments. ...

Análise morfológica e morfométrica de uma hemogregarina de Rhodnius brethesi Matta, 1919 (Hemiptera: Reduviidae: Triatominae) naturalmente infectados / Morphologic and morphometric analysis of a Hemogregarina of Rhodnius brethesi Matta, 1919 (Hemiptera, Reduviidae: Triatominae) naturally infected

Hemogregarinas são endoparasitos intraeritrocitários de uma grande variedade de vertebrados. Suaidentificação tem sido baseada principalmente em descrições morfológicas e morfométricas. Nestetrabalho, descreve-se a morfologia e morfometria de uma hemogregarina encontrada naturalmente infectando Rhodnius brethesi. Realizaram-se pesquisas parasitológicas na hemolinfa, no conteúdo intestinal e nas glândulas salivares de 174 R. brethesi selvagens. As descrições foram feitas com base em fotomicrografias digitais. As variáveis foram: morfologia externa, presença ou ausência de cápsula, comprimento, largura e número de esporozoítas em cada esporocisto; no caso dosesporozoítas, também foram analisados comprimento e largura nuclear, formato e posição do núcleo e presença ou ausência de pigmentos citoplasmáticos. Foram descritos oocistos, esporoblastos,esporocistos e esporozoítas de uma hemogregarina. Uma ninfa de R. brethesi de quarto estádio estava infectada simultaneamente por T. rangeli e hemogregarina. As características morfométricasobservadas nestes parasitos indicam que possivelmente se trata de uma nova hemogregarina ainda não relatada para este triatomíneo. A identificação do sangue de répteis como origem do repasto sanguíneo de R. brethesi, associada à grande presença do geconídeo Thecadactylus rapicaudaHouttuyn no ecótopo deste triatomíneo, sugere que este réptil seja o possível hospedeiro definitivo desta hemogregarina.