Analyses of Dengue Fever and Aedes aegypti (Diptera: Culicidae) Larval Habitats in a Tropical Urban Environment of Costa Rica using Geospatial and Mosquito Surveillance Technologies
Dengue is currently the most important arboviral disease globally and is usually associated with built environments in tropical areas. Control measures are currently focused on community participation in control of the vector Aedes aegypti and larval source reduction. In Costa Rica, dengue fever is a relatively recent re-emerging disease and has become a serious public health problem. Remotely sensed information can facilitate the study of urban mosquito-borne diseases like dengue by providing multiple temporal and spatial resolutions appropriate to investigate urban structure and ecological characteristics associated with infectious disease. Initial studies showed that although dengue is a serious public health problem in Costa Rica, there is a need for interdisciplinary scientific research to guide vector control. Therefore, the dengue situation in Puntarenas, Costa Rica, and applications of remote sensing to study infectious diseases like dengue within urban environments was analyzed. Satellite imagery of high and medium spatial resolution was obtained to evaluate relationships between urban structure and incidence of dengue fever at the locality level. Using the satellite imagery, a geographical sampling method was developed and applied for seasonal entomological field surveys in Puntarenas. Very high resolution imagery from QuickBird was utilized to determine the relationships between Ae. aegypti larval habitat abundance and tree cover or built areas. Results showed that the most relevant Ae. aegypti larval habitats in Puntarenas were outdoor miscellaneous containers, cans and plastic food containers that fill with rain water in the wet season, while washtubs were the most productive habitats in the dry season. Dengue incidence and abundance of larval habitats in the urban environment were directly associated with tree cover and inversely associated with built areas. Environmental conditions and urban structure, as well as human behavior were related in different ways to dengue incidence and Ae. aegypti larval habitats. Overall, remotely sensed information was useful in developing sampling strategies for field surveys and determining factors within the urban environment that may promote persistence of mosquito larval habitats and increased dengue risk. The geographical methods and relationships revealed will be useful in determining target areas for more efficient vector control.
Advisor:John C. Beier; Douglas O. Fuller; Kristopher L. Arheart; Clyde B. McCoy; Dave D. Chadee; Arba Ager
School:University of Miami
School Location:USA - Florida
Source Type:Master's Thesis
Date of Publication:12/21/2007