Doctor of Philosophy (PhD)


Pathobiological Sciences

Document Type



From within their ecologic niches, zoonotic viruses emerge from animal reservoirs into the edges and centers of human habitation to exploit opportunities for unabated transmission within immunologically–naïve populations. Our understanding of where, in whom, and how these viruses emerge is under direct challenge, driving the evolution of modern infectious disease epidemiology within a rapidly-connected global community. The studies presented herein are based on analyses of both aggregate and case-level data, which, we argue, provide unique insight into the complexities of transmission, co-infection, and clinical sequelae occurring within, and arising from, epidemics of emerging zoonotic viruses. In Chapter II, we investigate differences in disease severity between single- and multi-serotype dengue virus infections, and examine the clinical presentation of patients with dengue versus patients with dengue virus-Leptospira co-infection. Our objective was to construct a diagnostic algorithm to aid clinicians in the early recognition and treatment of patients with multi-pathogen infections. In Chapter III, we reconstruct a six-person transmission chain of Ebola virus disease in Liberia. We analyze the individual behaviors and epidemic control measures that contributed to, and interrupted, transmission. Finally, in Chapter IV, we present a case series of pain profiles and functional disability among survivors of Ebola virus disease, a contribution to the newly-recognized post-Ebola virus disease syndrome.

Our research contributes three principal implications for clinical and public health practice. In Norte de Santander, Colombia, we provide the first prevalence estimates of dengue virus multi-serotype infection and dengue virus-Leptospira co-infection. Identifying the reservoirs of pathogenic Leptospira spp. in Los Patios, and initiating public and clinical education campaigns, will be important interventions to mitigate environmental persistence, prevent additional cases, and encourage early initiation of antibiotic therapy. From case investigations in Liberia, we identify sweat as an under-recognized driver of the Ebola virus disease epidemic, and discuss the importance of social distancing to interrupt transmission. Finally, we describe the clinical symptoms and longitudinal disability experience of three Ebola virus disease survivors to contribute to the growing evidence of a post-viral syndrome in survivors.



Committee Chair

Mores, Christopher

Available for download on Tuesday, May 19, 2020