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bioRxiv · 10.1101/312397

Exploring how generation intervals link strength and speed of epidemics

Park, S. W.·Champredon, D.·Weitz, J.·Dushoff, J.
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Abstract

Infectious-disease outbreaks are often characterized by the reproductive number and exponential rate of growth r. provides information about out-break control and predicted final size. Directly estimating is difficult, while r can often be estimated from incidence data. These quantities are linked by the generation interval - the time between when an individual is infected by an infector, and when that infector was infected. It is often infeasible to ob-tain the exact shape of a generation-interval distribution, and to understand how this shape affects estimates of . We show that estimating generation interval mean and variance provides insight into the relationship between and r. We use examples based on Ebola, rabies and measles to explore approximations based on gamma-distributed generation intervals, and find that use of these simple approximations are often sufficient to capture the r- relationship and provide robust estimates of .

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Park, S. W., Champredon, D., Weitz, J., Dushoff, J.. 2018-05-02. Exploring how generation intervals link strength and speed of epidemics. https://doi.org/10.1101/312397

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