My laboratory is interested in research directed toward the identification, isolation and characterization of genetic factors associated with vector competence of the mosquito Aedes aegypti for dengue virus. Dengue virus (family Flaviridae) occurs as 4 serotypes that are biologically transmitted between humans principally by Aedes aegypti. This virus causes a nonspecific febrile illness termed dengue fever and is sometimes manifested in a severe and possibly fatal form, dengue hemorrhagic fever (DHF). Dengue is a threat to >2.5 billion people, with an annual incidence estimated at 50-100 million and several hundred thousand cases of DHF with ~24,000 cases per year. No effective vaccine candidates are available or soon anticipated for preventing dengue transmission. Our long-term goal is to improve existing strategies or develop novel dengue disease control strategies based on disrupting the pathogen life cycle.

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A wealth of information exists documenting genetic variability in dengue vector competence among Aedes aegypti populations both within and among geographic locations. In addition to these direct effects, other biotic and abiotic factors interact and influence phenotypic variance in dengue vector competence. The period from ingestion of an infective blood meal to being competent for oral transmission of the virus is defined as the extrinsic incubation period (EIP) in the mosquito. The length of the EIP can vary significantly among and within viruses and mosquito hosts and is influenced by environmental factors including temperature, larval nutrition and infective titer of the virus. Some factors known to influence vector competence, such as adult body size, are also determined by genetic and environmental factors. We are employing an integrated approach to investigating molecular aspects of dengue vector competence that will rapidly transition information gained from laboratory studies into field studies. We have a long-standing program to investigate the population dynamics of Aedes aegypti in Trinidad and Tobago, and are planning for additional efforts in Haiti and Cuba. These efforts are conducted in conjunction with vector control efforts by the respective Ministries of Health. Specific projects include investigations of mosquito population structure at the broad and local levels, sibship analysis and dispersal behavior, dengue vector competence relative to adult body size, and population dynamics of insecticide resistance. For additional information please visit my lab web page.