Prothonotary Warbler by Michelle Davis
 
 

My research interests center around the ecology of infectious diseases and parasites and the impact these pathogens have on their hosts. Birds have been a favorite model system for host-parasite interactions for many years, and the recent emergence of several avian viruses in humans (e.g. West Nile virus in North America and H5N1 the “Bird Flu” in Asia) have made understanding the dynamics of such systems particularly important.

I am currently working with Dr. Jennifer Owen and Dr. Mary Garvin (Oberlin College) on a project investigating the role of migration stress and testosterone-induced immune suppression in the recrudescence of West Nile virus (WNV, Flaviviridae, Flavivirus) and Eastern Equine Encephalitis virus (Togaviridae, Alphavirus) in Gray Catbirds (Dumetella carolinensis).

Additionally, I am planning a similar project on the role of migration and breeding hormones in the recrudescence of protozoan blood parasites (Haemoproteus spp.) in Gray Catbirds. Haemoproteus spp. are common parasites of many avian species that are transmitted by several arthropod vectors. The initiation of the annual cycle of transmission of Haemoproteus is not fully understood, although it is believed that either the stress of migration or breeding or a combination of both events acts to suppress the immune system and allow the recrudescence of latent infections in the spring. This relapse would coincide with peaks in vector abundance, creating a prime opportunity for the spread the parasite throughout the avian host population (Garvin et al. 2003). My goal is to design an experiment capable of teasing apart the influence of these factors.

My other research interests include the impact of coinfection on the level of circulating infectious particles. For example, would a bird simultaneously infected with a hematozoan and a virus have a higher parasitemia and viremia than a bird infected with either one of the pathogens separately? I am also interested in the identification of non-mosquito vectors for WNV and their importance to the overall maintenance of the virus in the environment.

Garvin, M.C., J.P. Basbaum, R.M. Ducore, and K.E. Bell. 2003. Patterns of Haemoproteus beckeri parasitism in the gray catbird (Dumatella carolinenesis) during the breeding season. Journal of Wildlife Ecology. 39(3): 582-587.

Department of Biological Sciences
The University of Southern Mississippi
118 College Drive # 5018
Hattiesburg, MS 39406-0001
(601)266-4394

amanda.j.williams@usm.edu

 

 

 

The University of Southern Mississippi. Last modified: 25 May, 2009 . Questions and Comments?
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