Background: Hotspot detection and characterization has played an increasing role in understanding the maintenance and transmission of zoonotic pathogens. Identifying the specific environmental factors (or their correlates) that influence reservoir host abundance help increase understanding of how pathogens are maintained in natural systems and are crucial to identifying disease risk. However, most recent studies are performed at macro-scale and describe broad temporal patterns of population abundances. Few have been conducted at a microscale over short time periods that better capture the dynamical patterns of key populations. These finer resolution studies may better define the likelihood of local pathogen persistence. This study characterizes the landscape distribution and spatio-temporal dynamics of Oligoryzomys fulvescens (O. fulvescens), an important mammalian reservoir in Central America. Methods: Information collected in a longitudinal study of rodent populations in the community of Agua Buena in Tonosí, Panama, between April 2006 and December 2009 was analyzed using non-spatial analyses (box plots) and explicit spatial statistical tests (correlograms, SADIE and LISA). A 90 node grid was built (raster format) to design a base map. The area between the nodes was 0.09 km2 and the total study area was 6.43 km2 (2.39 x 2.69 km). The temporal assessment dataset was divided into four periods for each year studied: the dry season, rainy season, and two months-long transitions between seasons (the months of April and December). Results: There were heterogeneous patterns in the population densities and degrees of dispersion of O. fulvescens that varied across seasons and among years. The species typically was locally absent during the late transitional months of the season, and re-established locally in subsequent years. These populations re-occurred in the same area during the first three years but subsequently re-established further south in the final year of the study. Spatial autocorrelation analyses indicated local populations encompassed approximately 300–600 m. The borders between suitable and unsuitable habitats were sharply demarcated over short distances. Conclusion: Oligoryzomys fulvescens showed a well-defined spatial pattern that evolved over time, and led to a pattern of changing aggregation. Thus, hot spots of abundance showed a general shifting pattern that helps explain the intermittent risk from pathogens transmitted by this species. This variation was associated with seasonality, as well as anthropogenic pressures that occurred with agricultural activities. These factors help define the characteristics of the occurrence, timing, intensity and duration of synanthropic populations affected by human populations and, consequently, possible exposure that local human populations experience.
|Original language||English (US)|
|Journal||PLoS neglected tropical diseases|
|State||Published - Feb 19 2016|
Bibliographical noteFunding Information:
We thank the International Centers for Infectious Diseases Research (ICIDR) program of the National Institutes of Health, Ministry of Health, University of New Mexico, Gorgas Memorial Institute for Health Studies, Panamanian Institute of Livestock and Agricultural Research, Ministry of Agricultural Development, Empresa de Transmisión Electrica S.A. and National Environment Authority for their support. We also thank individuals from the communities, several state organizations, and the rodent ecology team of the Ministry of Health and Gorgas Memorial Institute for Health Studies, especially Dr. Eustiquio Broce, Omar Vargas, Francisco Crespo, Ricardo Rodriguez, Juan Bosco Navarro, Ricardo Cedeño, Carlos Falconet, Jose Montenegro, Miguel Vergara, Victor Dominguez, Ariel Perez, Joel Gonzalez, Algis Vergara and Daniel Gonzalez for support during fieldwork. The authors thank to Sierra Armién Funk for the editing of the manuscript. Finally, we thank to Rosa Enith Carrillo de Vargas for its significant administrative support of the Department of Research in Emerging and Zoonotic Infectious Diseases, Gorgas Memorial Institute for Health Studies.
© 2016 Armién et al.