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bioRxiv · 10.1101/285080

Using biological control data to understand host-pathogen dynamics

Mihaljevic, J. R.·Polivka, K. M.·Mehmel, C. J.·Li, C.·Dukic, V.·Dwyer, G.
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Abstract

A key assumption of models of infectious disease is that population-scale spread is driven by transmission between host individuals at small scales. This assumption, however, is rarely tested, likely because observing disease transmission between host individuals is non-trivial in many infectious diseases. Quantifying the transmission of insect baculoviruses at a small scale is in contrast straightforward. We fit a disease model to data from baculovirus epizootics (= epidemics in animals) at the scale of whole forests, while using prior parameter distributions constructed from branch-scale experiments. Our experimentally-constrained model fits the large-scale data very well, supporting the role of small-scale transmission mechanisms in baculovirus epizootics. We further compared our experimentally-based model to an unconstrained model that ignores our experimental data, serving as a proxy for models that include large-scale mechanisms. This analysis supports our hypothesis that small-scale mechanisms are important, especially individual variability in host susceptibility to the virus. Comparison of transmission rates in the two models, however, suggests that large-scale mechanisms increase transmission compared to our experimental estimates. Our study shows that small-scale and large-scale mechanisms drive forest-wide epizootics of baculoviruses, and that synthesizing mathematical models with data collected across scales is key to understanding the spread of infectious disease.

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Mihaljevic, J. R., Polivka, K. M., Mehmel, C. J., Li, C., Dukic, V., Dwyer, G.. 2018-03-19. Using biological control data to understand host-pathogen dynamics. https://doi.org/10.1101/285080

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