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Center for Nonlinear Studies |
Historically, our understanding of disease-host systems has been built upon a population-based rather than community-based approach: epidemiologists have traditionally studied infectious disease at the level of a single pathogen species infecting a single host species. This has led to a significant body of epidemiological research devoted to understanding the precise mechanisms underlying host-pathogen dynamics in isolation: an oversimplification of the web of ecological and immunological interactions in which hosts and their pathogens persist and evolve. In this talk, I will briefly discuss the potential for interactions amongst multiple pathogens and apply a general theoretical framework for their study to the case of dengue: a mosquito-borne strain polymorphic disease. To understand how alternative hypotheses concerning dengue infection and transmission may explain observed multi-annual cycles in disease incidence, I adopt a mathematical approach that incorporates both ecological and immunological mechanisms. Contrary to perceived wisdom, patterns generated solely by antibody-dependent enhancement or heterogeneity in virus virulence are not consistent with serotype-specific notification data in important ways. Furthermore, to generate epidemics with the characteristic signatures observed in data, a combination of seasonal variation in vector demography and, crucially, a short-lived period of cross-immunity is sufficient. Finally, I demonstrate how understanding the persistence and eradication of dengue serotypes critically depends on the alternative assumed mechanisms.
Host: Gerardo Chowell-Puente