Agrochemicals increase risk of human schistosomiasis by supporting higher densities of intermediate hosts

• Type of Material: Article
• Authors: Neal T. Halstead, University of South Florida; Christopher M. Hoover, University of California Berkeley; Arathi Arakala, Monash University; David Civitello, Emory University; Giulio A. De Leo, Stanford University; Manoj Gambhir, Monash University; Steve A. Johnson, University of Florida; Nicolas Jouanard, Center for Research; Kristin A. Loerns, University of South Florida; Taegan A. McMahon, University of Tampa; Raphael Ndione, Centre de Recherche Biomédicale Espoir pour la Santé; Karena Nguyen, University of South Florida; Thomas R. Raffel, Oakland University; Justin V. Remais, University of California Berkeley; Gilles Riveau, Centre de Recherche Biomédicale Espoir pour la Santé; Susanne H. Sokolow, Stanford University; Jason R. Rohr, University of South Florida
• Language: English
• Date: 2018-02-26
• Publisher: Nature Publishing Group: Nature Communications
• Publication Version: Final Published Version
• Copyright Statement: © 2018 The Author(s).
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1038/s41467-018-03189-w
• Title of Journal or Parent Work: Nature Communications
• ISSN: 2041-1723
• Volume: 9
• Issue: 1
• Start Page: 837
• End Page: 837
• Grant/Funding Information: This research was supported by grants from the National Science Foundation (EF-1241889), National Institutes of Health (R01GM109499, R01TW010286), US Department of Agriculture (NRI 2006-01370, 2009-35102-0543), and US Environmental Protection Agency (CAREER 83518801) to J.R.R., and National Institutes of Health (K01AI091864) and the National Science Foundation (EAR-1646708, EAR-1360330) to J.V.R.; a University of Florida Research Innovation Award to J.R.R. and S.A.J.; an Oakland University Research Excellence Fund award to T.R.R; and Dana and Delo Faculty Development Grants from the University of Tampa (T.A.M.). S.H.S. and G.A.D.L were supported by National Science Foundation (CNH grant # 1414102), the Bill and Melinda Gates Foundation, National Institutes of Health (R01GM109499, R01TW010286-01), Stanford GDP SEED (grant # 1183573-100-GDPAO), the SNAP-NCEAS working group “Ecological levers for health: Advancing a priority agenda for Disease Ecology and Planetary Health in the 21st century” and the NIMBioS-supported working group on the Optimal Control of Environmentally Transmitted Disease.
• Keywords: CRAYFISH PROCAMBARUS-CLARKII; SNAIL POPULATIONS; Science & Technology - Other Topics; INFECTION; PRAWN MACROBRACHIUM-ROSENBERGII; TREMATOCRANUS-PLACODON; BULINUS-NYASSANUS; LAKE MALAWI; PREDATION; BIOMPHALARIA; Science & Technology; Multidisciplinary Sciences; LABORATORY POPULATIONS
• Research Categories: Environmental Sciences; Biology, General; Health Sciences, Epidemiology

Abstract

Schistosomiasis is a snail-borne parasitic disease that ranks among the most important water-based diseases of humans in developing countries. Increased prevalence and spread of human schistosomiasis to non-endemic areas has been consistently linked with water resource management related to agricultural expansion. However, the role of agrochemical pollution in human schistosome transmission remains unexplored, despite strong evidence of agrochemicals increasing snail-borne diseases of wildlife and a projected 2- to 5-fold increase in global agrochemical use by 2050. Using a field mesocosm experiment, we show that environmentally relevant concentrations of fertilizer, a herbicide, and an insecticide, individually and as mixtures, increase densities of schistosome-infected snails by increasing the algae snails eat and decreasing densities of snail predators. Epidemiological models indicate that these agrochemical effects can increase transmission of schistosomes. Identifying agricultural practices or agrochemicals that minimize disease risk will be critical to meeting growing food demands while improving human wellbeing.