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Pej Rohani

Speaker Photo
Pej Rohani
UGA Ecology
204 Caldwell Hall

Early warning signals for disease re-emergence


Developing statistical methods for anticipating the emergence or reemergence of infectious diseases is both important and timely; however, traditional model-based approaches are stymied by uncertainty surrounding the underlying drivers, especially in the context of disease (re-)emergence. In this talk, I will demonstrate an operational, mechanism-agnostic detection algorithm for disease (re-)emergence based on early warning signals (EWSs) derived from the theory of critical slowing down. Specifically, we used computer simulations to train a supervised learning algorithm to detect the dynamical footprints of (re-)emergence present in epidemiological data. Our algorithm was then challenged to forecast the slowly manifesting, spatially replicated reemergence of mumps in England in the mid-2000s and pertussis post-1980 in the United States. Our method successfully anticipated mumps re-emergence 4 years in advance, during which time mitigation efforts could have been implemented. From 1980 onwards, our model identified resurgent states with increasing accuracy, leading to reliable classification starting in 1992. Additionally, we successfully applied the detection algorithm to 2 vector-transmitted case studies, namely, outbreaks of dengue serotypes in Puerto Rico and a rapidly unfolding outbreak of plague in 2017 in Madagascar. Taken together, these findings illustrate the power of theoretically informed machine learning techniques to develop early warning systems for the (re)emergence of infectious diseases.

About the Speaker

Pej Rohani is Regents’ professor and the UGA athletics association professor at the University of Georgia.  He is also the Associate Dean for Academic Affairs in the Odum School of Ecology and the Deputy Director of Center for Influenza Disease and Emergence Research.  He works on the population biology of infectious disease systems, using computational modeling and statistics.  His main research interests have focused on the transmission dynamics of microparasitic diseases, including influenza, pertussis and covid-19.  He has co-authored a book and written published more than 165 papers, including publications in Science, Nature, Lancet, PNAS and PLoS Biology.  He has received fellowships from the Guggenheim Foundation, the American Association for the Advancement of Science and the Ecological Society of America.

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