Event Type:

Defense

Date/Time:

Tuesday, June 5, 2012 - 03:00 to 03:30

Location:

GRAF 306

Guest Speaker:

Margaret-Rose Leung

Institution:

Oregon State University

Abstract:

Barley/cereal yellow dwarf virus (B/CYDV) is a suite of aphid-vectored

pathogens that affect diverse host communities, including

economically-important crops. Coinfection of a single host by multiple

strains of B/CYDV can result in elevated virulence, incidence, and

transmission rates. We construct and analyze models for a single--host, two--pathogen

strains, and n vector species, modeled by systems of

nonlinear ordinary differential equations. A single parameter describes the

degree of relatedness of the strains and the amount of cross-protection

between them.

We compute the basic and type reproduction numbers for the model and

analytically prove the (conditional) stability of the disease-free

equilibrium. We demonstrate numerically that, although the basic

reproduction number describes stability of the disease-free equilibrium, the

type reproduction numbers better describe the individual behavior of each

strain and the dynamics of coinfection. We then conduct a sensitivity

analysis of the components of the endemic equilibrium and confirm that the

disease transmission rates play a large role in the equilibrium prevalences

of infection and coinfection.

Host: