Edwin C. Hahn, III
Associate Dean for Research and Advanced Studies, Veterinary Medicine Administration
Associate Professor, Pathobiology
Assistant Dean, Research Leadership Veterinary Program
Professional Interests: Virology,
immunopathogenesis, persistent viruses, cellular immune function, transmission
biology of herpesvirus in wildlife, molecular epidemiology, pseudorabies,
infectious diseases of swine.
Current research interests are in the pathogenesis of persistent viral infections.
Most efforts have been in the area of immunopathogenesis. The ability of viruses
to induce immunosuppression and autoimmune disease have been studied using such
viral systems as the parvovirus, Aleutian disease virus, the herpesvirus, pseudorabies,
and recently the artirivirus, PRRS. In the pseudorabies virus system in swine,
my associates and I are looking at the role of cellular immunity in resistance
to the disease. The use of a herpesvirus in its natural host has advantages as
a model system for human herpes infections and their control. The early pathogenesis
of the infection is critical to the outcome of the disease. This stage must be
probed in detail with immunological and molecular methods. We are finding that
this herpesvirus can infect some subsets of T cells and almost all monocytes
and macrophages. Marked functional changes in these immune effector cells occur
after infection. Certain cellular cytotoxic lymphocytes, mixed lymphocyte reactors
and natural killer cells are susceptible to infection. Losses in immune effector
function has important consequences for the severity of the disease outcome.
Infection of B cells is limited. In fact recent results suggests that the virus
inhibits programmed cell death in these cells.
The US is currently involved in a national eradication program for pseudorabies
virus, a herpesvirus of swine. Keeping domestic pigs free of pseudorabies virus
will depend on controlling wildlife reservoirs of the virus. Over 3 million feral
swine roam free over much of the southern half of our country. Many of these
are infected with the virus. We are now looking at the transmission biology of
the natural infection in feral swine. We are also characterizing isolates of
pseudorabies from feral swine at the molecular level using DNA sequencing and
RNase protection assays. These studies will be used for molecular epidemiology
of the virus and investigations of the natural history of the emerging disease
in domestic pigs.
Selected Publications:
Weigel RM, Hahn EC and Scherba G. (2003) Survival and immunization of raccoons Veterinary Microbiology 92:19-24.
Goldberg TL, Weigel RM, Hahn EC and Scherba G. (2001) Comparative utility of restriction fragment length polymorphism analysis and gene sequencing to the molecular epidemiological investigation of a viral outbreak. Epidemiol. Infect. 126: 415-424.
Romero CH, Meade PN, Shultz JE, Chung HY, Gibbs EP, Hahn EC and Lollis G. (2001) Venereal transmission of pseudorabies viruses indigenous to feral swing. Journal of Wildlife Diseases 37:289-296.
Goldberg TL, Weigel RM, Hahn EC and Scherba G. (2000) Associations between genetics, farm characteristics and clinical disease in field outbreaks of porcine reproductive and respiratory syndrome virus. Prev. Vet. Med. 43:293-302
Goldberg TL, Hahn EC Weigel RM and Scherba G. (2000) Genetic geographical and temporal variation of porcine reproductive and respiratory syndrome virus in Illinois. Journal of General Virology. 81(Part 1):171-179.
Müller T, Conraths FJ and Hahn EC.
(2000) Pseudorabies virus infection (Aujeszky's disease) in wild swine. Infect
Dis Rev 2(1): 27-34.
