The Medical Entomology Laboratory, a component of the Urban Science and Ecology (USE) Program in the Department of Natural Sciences, provides an opportunity for undergraduate students to conduct research on arthropods of medical and veterinary importance.
The Medical Entomology Laboratory is currently involved in research in the following fields:
Mosquito Biology Project
One of the most active research groups in the laboratory is the Mosquito Biology Project. Texas encompasses a wide range of environmental conditions from sea level to mountainous terrain and, within this diverse area, 80 species of mosquitoes abound with several species incriminated as disease vectors. Ongoing studies on the biology and ecology of many of these mosquitoes are yielding fundamental knowledge of the behavior, breeding preferences, flight range, survival rates, and other basic mosquito characteristics. The major endeavor of the research conducted by students in the Mosquito Biology Project has been the characterization of mosquito species involved in the transmission of pathogens of medical importance in Texas. Research has concentrated on what we have termed vector competence. Vector competence is the efficiency of a mosquito species or subpopulation of a species in acquiring and transmitting a pathogen.
Mosquito Vector Biology
Culex quinguefasciatus, the southern house mosquito, is of major epidemiological importance in the transmission of arbovirus encephalitis. St. Louis Encephalitis (SLE) has occurred in Houston more frequently than in any other geographical area of Texas. Mosquitoes are collected on a regular basis to quantify the dynamics of mosquito vector populations and virus infection rates. The objectives for the near future are to study the dynamics of adult dispersal, larval development, oviposition of Culex quinquefasciatus, and other SLE mosquito vectors under field conditions. The significance of elucidating these phenomena is that they should provide an accurate target for effecting vector control. Field investigations are enhanced through voluntary cooperation and collaboration between UHD scientists, Texas mosquito control agencies, and the Texas Department of Health.
Dog Heartworm Research
The Mosquito Biology Project is also investigating the vector competence of mosquitoes involved in the transmission of dog heartworm, Dirofilaria immitis. The relationship between D. immitis and its mosquito vectors is complex. Two species of mosquitoes of particular interest are Aedes aegypti and Ae. albopictus. Aedes aegypti, the yellow fever mosquito, is widely but sporadically distributed throughout Texas. Aedes aegypti is a highly domesticated mosquito that can complete its entire life cycle within the confines of a single human dwelling. Since its introduction into the United States in the mid-1980s, Ae. albopictus, the Asian tiger mosquito, has become a major pest species in the urban areas of Texas. We are studying the biology, natural history, and behavior of these mosquito species, especially as these factors relate to their ability to transmit heartworms to dogs and cats in Texas.
Control of Vector Mosquitoes
Students in the Mosquito Biology Project also conduct research to determine the effectiveness of commercial formulations of the microbial insecticide, Bacillus thuringiensis israelensis, against larvae of selected mosquito species. Assay procedures generally have followed standard practices, with tests conducted against field-collected mosquito larvae in the laboratory and natural populations of mosquito larvae in the field. Field evaluations are performed in several different mosquito habitats, including roadside ditches, pastures, standing ponds, catch basins, and salt marshes.
Jeffrey W. Flosi Ph.D., BCE
Associate Professor of Biology and Microbiology