Amazonian Triatomine Biodiversity and the Transmission of Chagas Disease in French Guiana: In Medio Stat Sanitas

• Published in: PLoS neglected tropical diseases Vol. 10; no. 2; p. e0004427
• Main Authors: Péneau, Julie, Nguyen, Anne, Flores-Ferrer, Alheli, Blanchet, Denis, Gourbière, Sébastien
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 11-02-2016; Public Library of Science (PLoS)
• Subjects: Analysis; Animals; Arthropoda; Biodiversity; Biology and Life Sciences; Chagas disease; Chagas Disease - epidemiology; Chagas Disease - transmission; Disease transmission; Double jeopardy; Earth Sciences; Ecology and Environmental Sciences; Ecology, environment; Female; French Guiana - epidemiology; Genetic aspects; Humans; Infections; Infectious diseases; Insect Vectors - classification; Insect Vectors - genetics; Insect Vectors - physiology; Life Sciences; Male; Medicine and Health Sciences; Panstrongylus; Panstrongylus geniculatus; Parasitic diseases; Pharmaceutical industry; Protozoa; Public health; Rhodnius pictipes; Risk factors; Seasons; Studies; Triatominae; Triatominae - classification; Triatominae - genetics; Triatominae - physiology; Tropical diseases; Trypanosoma cruzi; Zoonoses; French Guiana; ASW, French Guiana; ASW, Guyana; Vector-borne diseases; Species diversity; Disease vectors; Geographic distribution; Chagas disease; Seasons; Biodiversity; Trypanosoma cruzi
• ISSN: 1935-2735; 1935-2727; 1935-2735
• DOI: 10.1371/journal.pntd.0004427

The effects of biodiversity on the transmission of infectious diseases now stand as a cornerstone of many public health policies. The upper Amazonia and Guyana shield are hot-spots of biodiversity that offer genuine opportunities to explore the relationship between the risk of transmission of Chagas disease and the diversity of its triatomine vectors. Over 730 triatomines were light-trapped in four geomorphological landscapes shaping French-Guiana, and we determined their taxonomic status and infection by Trypanosoma cruzi. We used a model selection approach to unravel the spatial and temporal variations in species abundance, diversity and infection. The vector community in French-Guiana is typically made of one key species (Panstrongylus geniculatus) that is more abundant than three secondary species combined (Rhodnius pictipes, Panstrongylus lignarius and Eratyrus mucronatus), and four other species that complete the assemblage. Although the overall abundance of adult triatomines does not vary across French-Guiana, their diversity increases along a coastal-inland gradient. These variations unravelled a non-monotonic relationship between vector biodiversity and the risk of transmission of Chagas disease, so that intermediate biodiversity levels are associated with the lowest risks. We also observed biannual variations in triatomine abundance, representing the first report of a biannual pattern in the risk of Chagas disease transmission. Those variations were highly and negatively correlated with the average monthly rainfall. We discuss the implications of these patterns for the transmission of T. cruzi by assemblages of triatomine species, and for the dual challenge of controlling Amazonian vector communities that are made of both highly diverse and mostly intrusive species.