Recent unique findings from our laboratory suggest that the togavirus, eastern equine encephalomyelitis (EEE) virus, causes significant cytopathology in the midgut of its mosquito vector, Culiseta melanura. This observation challenges previous beliefs regarding the benign nature of mosquito infection with arboviruses, and suggests potential mechanisms which may 1) facilitate rapid virus dissemination within the mosquito and transmission to vertebrates, and 2) act to alter the virus gene pool during vector infection. Using light and electron microscopy, we propose to further evaluate togavirus-induced vector pathology in the EEE virus -Cs. melanura system, as well as in another medically important alphavirus, Venezuelan equine encephalomyelitis virus, in its enzootic mosquito vector, Culex taeniopus. These studies will establish the effect of togavirus infection on the biological fitness of the mosquito, including blood digestion, reproduction, host seeking and longevity, and define the relationship between midgut pathology and virus dissemination in the vector. Using a molecular approach, we will examine the genetic composition of arbovirus populations over time during various stages of rapid and persistent mosquito infection. Our proposed research, which couples classical entomological techniques with electron microscopy and molecular biology, will reveal mechanisms of arbovirus-vector coevolution, which will lead to better understanding of the epidemiology of togaviral diseases.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI026787-02
Application #
3140741
Study Section
Tropical Medicine and Parasitology Study Section (TMP)
Project Start
1988-08-01
Project End
1993-07-31
Budget Start
1989-08-01
Budget End
1990-07-31
Support Year
2
Fiscal Year
1989
Total Cost
Indirect Cost
Name
University of Maryland College Park
Department
Type
Earth Sciences/Resources
DUNS #
City
College Park
State
MD
Country
United States
Zip Code
20742
Weaver, S C; Brault, A C; Kang, W et al. (1999) Genetic and fitness changes accompanying adaptation of an arbovirus to vertebrate and invertebrate cells. J Virol 73:4316-26
Scott, T W; Lorenz, L H (1998) Reduction of Culiseta melanura fitness by eastern equine encephalomyelitis virus. Am J Trop Med Hyg 59:341-6
Day, J F; Stark, L M; Zhang, J T et al. (1996) Antibodies to arthropod-borne encephalitis viruses in small mammals from southern Florida. J Wildl Dis 32:431-6
Lorenz, L H; Scott, T W (1996) Detection of multiple bloodfeeding in Culiseta melanura using a histologic technique. J Am Mosq Control Assoc 12:135-6
Monroy, A M; Scott, T W; Webb, B A (1996) Evaluation of reverse transcriptase polymerase chain reaction for the detection of eastern equine encephalomyelitis virus during vector surveillance. J Med Entomol 33:449-57
Putnam, J L; Scott, T W (1995) Blood-feeding behavior of dengue-2 virus-infected Aedes aegypti. Am J Trop Med Hyg 52:225-7
Putnam, J L; Scott, T W (1995) The effect of multiple host contacts on the infectivity of dengue-2 virus-infected Aedes aegypti. J Parasitol 81:170-4
Putnam, J L; Scott, T W (1995) Evaluation of enemas for exposing Aedes aegypti to suspensions of dengue-2 virus. J Am Mosq Control Assoc 11:369-71
Putnam, J L; Clark, G G; Scott, T W (1995) Failure of immune sera to neutralize dengue-2 virus in intrathoracically inoculated Aedes aegypti. J Am Mosq Control Assoc 11:372-4
Weaver, S C; Hagenbaugh, A; Bellew, L A et al. (1994) Evolution of alphaviruses in the eastern equine encephalomyelitis complex. J Virol 68:158-69

Showing the most recent 10 out of 28 publications