On Wednesday representatives from the Harvard School of Public Health
will be coming to talk about their research and hold an info session
about the school. Mel Larson, from the Center for Communicable Disease
Dynamics (CCDD) at HSPH, will also be present to hand out information to
students, talk about the CCDD and the opportunities they have there for
the spring and summer, and discuss resources HSPH offers students to
help with their applications.
When: Wednesday, October 22 at 5pm
Where: Kemeny 004
The information for the talk is found below:
Phenotypic variation allows for heighted pathogen virulence
Lauren M. Childs, Cayley Bowles, Caroline O. Buckee
Abstract:
Theoretical frameworks for understanding why some pathogens cause
virulence in their hosts suggest that pathogens evolve to maximize their
reproductive number, a quantity inextricably linked to pathogen growth
within the host. Since pathogen-induced mortality is an unavoidable
consequence of increased pathogen growth and transmission, a trade-off
typically emerges, leading to maximized fitness at an intermediate
virulence. While these frameworks are a useful starting point to think
about transmission-virulence tradeoffs, they implicitly assume that each
pathogen is associated with only a single virulence phenotype encoded
by the genotype and need to be re-evaluated in the context of pathogens
that exhibit variable phenotypes in identical hosts, such as the
diversity of clinical syndromes observed in malaria infections. We
develop a theoretical model to test whether a single genotype that gives
rise to multiple disease phenotypes can account for the existence of
heterogeneous disease outcomes. We find that variation in gene-specific
virulence and transmission within a single strain can indeed contribute
to its success, expanding regions of coexistence and dominance in
competition with a strain having a single optimized virulence. Our
results further demonstrate that expressing multiple virulence
phenotypes, even when one is highly virulent, can be advantageous for a
strain.
Visit http://www.math.dartmouth.edu/~siamchapter/index.html for more information.