Anthropogenic landscape decreases mosquito biodiversity and drives malaria vector proliferation in the Amazon rainforest

Author(s)

Chaves, Leonardo Suveges Moreira ^[1] ; Bergo, Eduardo Sterlino ^[2] ; Conn, Jan E. ^{[3, 4]} ; Laporta, Gabriel Zorello ^[5] ; Prist, Paula Ribeiro ^[6] ; Sallum, Maria Anice Mureb ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Saude Publ, Dept Epidemiol, Sao Paulo, SP - Brazil

^[2] Secretaria Estado Saude Sao Paulo, Superintendencia Controle Endemias, Araraquara, SP - Brazil

^[3] New York State Dept Hlth, Wadsworth Ctr, Albany, NY - USA

^[4] SUNY Albany, Dept Biomed Sci, Sch Publ Hlth, Albany, NY 12222 - USA

^[5] Ctr Univ Saude ABC, Fdn ABC, Setor Posgrad Pesquisa & Inovacao, Santo Andre, SP - Brazil

^[6] Univ Sao Paulo, Dept Ecol, Inst Biosci, Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: PLoS One; v. 16, n. 1 JAN 14 2021.
• Web of Science Citations: 2

Abstract

Inter-relationships among mosquito vectors, Plasmodium parasites, human ecology, and biotic and abiotic factors, drive malaria risk. Specifically, rural landscapes shaped by human activities have a great potential to increase the abundance of malaria vectors, putting many vulnerable people at risk. Understanding at which point the abundance of vectors increases in the landscape can help to design policies and interventions for effective and sustainable control. Using a dataset of adult female mosquitoes collected at 79 sites in malaria endemic areas in the Brazilian Amazon, this study aimed to (1) verify the association among forest cover percentage (PLAND), forest edge density (ED), and variation in mosquito diversity; and to (2) test the hypothesis of an association between landscape structure (i.e., PLAND and ED) and Nyssorhynchus darlingi (Root) dominance. Mosquito collections were performed employing human landing catch (HLC) (peridomestic habitat) and Shannon trap combined with HLC (forest fringe habitat). Nyssorhynchus darlingi abundance was used as the response variable in a generalized linear mixed model, and the Shannon diversity index (H') of the Culicidae community, PLAND, and the distance house-water drainage were used as predictors. Three ED categories were also used as random effects. A path analysis was used to understand comparative strengths of direct and indirect relationships among Amazon vegetation classes, Culicidae community, and Ny. darlingi abundance. Our results demonstrate that Ny. darlingi is negatively affected by H ` and PLAND of peridomestic habitat, and that increasing these variables (one-unit value at beta(0) = 768) leads to a decrease of 226 (P < 0.001) and 533 (P = 0.003) individuals, respectively. At the forest fringe, a similar result was found for H' (beta(1) = -218; P < 0.001) and PLAND (beta(1) = -337; P = 0.04). Anthropogenic changes in the Amazon vegetation classes decreased mosquito biodiversity, leading to increased Ny. darlingi abundance. Changes in landscape structure, specifically decreases in PLAND and increases in ED, led to Ny. darlingi becoming the dominant species, increasing malaria risk. Ecological mechanisms involving changes in landscape and mosquito species composition can help to understand changes in the epidemiology of malaria. (AU)

• FAPESP's process: 14/26229-7 - Latitudinal landscape genomics and ecology of Anopheles darlingi
• Grantee: Maria Anice Mureb Sallum
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 14/26855-5 - Landscape as regulator of Culicidae diversity and dynamics of Anopheles vectors in rural settlements with malaria cases in the Brazilian Amazon
• Grantee: Leonardo Suveges Moreira Chaves
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 14/09774-1 - Dynamics of malaria transmission under distinct landscape fragmentation thresholds
• Grantee: Gabriel Zorello Laporta
• Support Opportunities: BIOTA-FAPESP Program - Young Investigators Grants