PS 9-99 - Influences of food web dynamics on Chagas disease transmission in central America

Monday, August 8, 2016
ESA Exhibit Hall, Ft Lauderdale Convention Center

ABSTRACT WITHDRAWN

Christina Pilar Varian, University of Georgia; Nicole Gottdenker, University of Georgia; Azael Saldana, Gorgas Memorial Institute for Health Studies; Jose Calzada, Gorgas Memorial Institute for Health Studies

Background/Question/Methods:  The study of disease ecology incorporates community and food web ecology in a quantitative framework to understand species relationships within an ecosystem. Therefore, food webs can provide information on how species community structure influences the transmission of infectious disease agents. The zoonotic multi-host vector-borne pathogen, Trypanosoma cruzi, cycles between triatomine vectors and a variety of mammalian hosts, including humans, throughout the Americas. In Panama, T. cruzi is transmitted between the sylvatic vector, Rhodnius pallescens and mammalian arboreal hosts within the royal palm tree, Attalea butyracea. Research suggests that abundance of R. pallescens increases within palms in disturbed landscapes. This pattern in vector abundance may be a response to changes in intra-palm species communities along gradients of microhabitat and landscape disturbance across a matrix of land use change in central Panama. Eleven palm crown communities were sampled in peridomicile, pasture, and secondary forest habitat sites in La Chorrera and Trinidad de Las Minas, Panama. Palm dissection techniques and invertebrate and vertebrate observation and collecting methods were used to determine intra-palm crown community. Species community structure was analyzed and compared across palms using the food web network modeling program, Network 3D.  Rhodnius pallescensabundance was compared alongside community measurements and across each palm.

Results/Conclusions:  There was an increase in vector abundance within palms in peridomiciliary habitats. Species community composition varied across habitat types; forest palms contained greater vector predator diversity (i.e. arachnids) compared to pasture palms containing habitat tolerant (i.e. cockroaches) and species poor (including vertebrate blood meals) communities. It is suspected that the interaction between community composition/dynamics and microhabitat characteristics (i.e. palm crown humidity and temperature) drove differences in vector abundance across a landscape gradient. Long-term goals of this study include characterizing palm crown food webs of a larger number (N=50) palms across different habitat types in deforested landscapes. Food web analysis is a novel approach to understanding multi-host vector-borne dynamics and can be applied to determining natural methods of vector control. Results from this study can be further applied to the prediction, prevention, and management of Chagas disease in Latin America and understanding similar zoonotic disease systems.