Environmental variables associated with anopheline larvae distribution and abundance in Yanomami villages within unaltered areas of the Brazilian Amazon

Copyright
open access
Type
Date
2017
Journal Title
Journal ISSN
Volume Title
Publisher
Alternative Title
Affilliation
Advisor
Co-Advisor
Committee Member
Organizer
Coordinator(s)
Institutional author
Director
item.page.production
Screenplay
Producer
Recorder
Abstract
Many indigenous villages in the Amazon basin still suffer from a high malaria burden. Despite this health situation, there are few studies on the bionomics of anopheline larvae in such areas. This publication aims to identify the main larval habitats of the most abundant anopheline species and to assess their associations with some environmental factors. METHODS: We conducted a 19-month longitudinal study from January 2013 to July 2014, sampling anopheline larvae in two indigenous Yanomami communities, comprised of four villages each. All natural larval habitats were surveyed every two months with a 350 ml manual dipper, following a standardized larval sampling methodology. In a third study area, we conducted two field expeditions in 2013 followed by four systematic collections during the long dry season of 2014-2015. RESULTS: We identified 177 larval habitats in the three study areas, from which 9122 larvae belonging to 13 species were collected. Although species abundance differed between villages, An. oswaldoi (s.l.) was overall the most abundant species. Anopheles darlingi, An. oswaldoi (s.l.), An. triannulatus (s.s.) and An. mattogrossensis were primarily found in larval habitats that were partially or mostly sun-exposed. In contrast, An. costai-like and An. guarao-like mosquitoes were found in more shaded aquatic habitats. Anopheles darlingi was significantly associated with proximity to human habitations and larval habitats associated with river flood pulses and clear water. CONCLUSIONS: This study of anopheline larvae in the Brazilian Yanomami area detected high heterogeneities at micro-scale levels regarding species occurrence and densities. Sun exposure was a major modulator of anopheline occurrence, particularly for An. darlingi. Lakes associated with the rivers, and particularly oxbow lakes, were the main larval habitats for An. darlingi and other secondary malaria vectors. The results of this study will serve as a basis to plan larval source management activities in remote indigenous communities of the Amazon, particularly for those located within low-order river-floodplain systems.
Abstract
Abstract in Spanish
Abstract in French
Description
Keywords in Portuguese
Yanomami, Região Norte, Roraima, Região Amazônica, Malária
Keywords
Keywords in Spanish
Keywords in French
DeCS
Brasil, Saúde de Populações Indígenas, Índios Sul-Americanos, Estudos Epidemiológicos, Epidemiologia, Fatores de Risco, Vetores de Doenças, Doenças Parasitárias
Event Date
Previous version
Related Document
Means of dissemination
Duration
Duration
Original color system
Target audience context
Audience occupation
Educational Description
Evaluation
Peer Reviewed
Publication Status
Sponsorship
Latest version
Version
Event Location
Event title
Event Type
Citation
SÁNCHEZ-RIBAS, Jordi; OLIVEIRA-FERREIRA, Joseli; GIMNIG, John E.; PEREIRA-RIBEIRO, Cleomar; SANTOS-NEVES, Maycon Sebastião Alberto; SILVA-DO-NASCIMENTO, Teresa Fernandes. Environmental variables associated with anopheline larvae distribution and abundance in Yanomami villages within unaltered areas of the Brazilian Amazon. Parasites & Vectors, v. 10, n. 1, p. 571, 2017.
ISBN
ISSN
1756-3305
DOI
10.1186/s13071-017-2517-6
Defense Institution
Degree date
Defense location
Programa