PSA 104, F Sep 10, 3:40 -- 4:30

Speaker: Miriam Nuno, Cornell University

Title: A new approach to modeling multiple influenza strain dynamics
Authors: Miriam Nuno, Maia Martcheva, Carlos Castillo-Chavez

Abstract:
We develop a mathematical model that incorporates partial
cross-immunity to next-to-kin strains.
The immunity status of the host is the antibody level corresponding to
all the strains that each host has immunity to.
Antibody immune response of the host population
is captured by an index-set notation where the index specifies the
immune-competence level against a particular strain.
In contrast to previous modeling frameworks, the population here is
structured into non-intersecting subclasses. Since multiple infection with
influenza strains is unlikely to occur, we do not imbed superinfection
with the same or different strains as part of our model.
This framework allows for a biologically interpretable range of
cross-immunity levels as observed during the yearly influenza
epidemics (antigenic drift).
Using the proposed framework of cross-immunity, we provide specific
cases to illustrate the impact of the assumptions on the strain state
space. Furthermore, we utilize the proposed notation to provide
threshold conditions for the invasion of a new strain and show the
existence of an endemic multi-strain equilibrium in a particular case.