Epidemiology and control of canine rabies in heterogeneous populations.

In 2015, canine rabies was detected in the city of Arequipa, Peru. Since then, hundreds of rabid dogs have been detected in the city. Rabies is zoonotic and is almost invariably fatal once symptoms develop making persistent rabies virus transmission in a large urban center a serious public health threat. Rabies control in Arequipa consists of two prongs: focus control and mass dog vaccination. Focus control around a rabies case includes removal of exposed dogs, ring vaccination of susceptible dogs, and administration of post-exposure prophylaxis to exposed humans. Mass dog vaccination is the mainstay of rabies control worldwide. Despite previous successes in controlling canine rabies across Latin America and increased efforts in response to the current Arequipa outbreak, rabies virus transmission in the canine population of Arequipa remains ongoing. In this thesis, we analyzed the epidemiology of canine rabies virus in the context of control measures implemented in Arequipa, Peru. To inform assessments of focus control strategies, we conducted a spatial analysis of dog movement in Arequipa using GPS data from free-roaming dogs. We explored the theoretical effects of both focus control and mass dog vaccination through compartmental modeling of rabies dynamics. Finally, we developed a stochastic, metapopulation model to investigate how the timing of pulsed mass vaccination campaigns might affect canine rabies elimination prospects. We found that focus control efforts are likely insufficient considering heterogeneous dog movements facilitated by urban geographic features. The effects of both focus control and mass vaccination efforts were modeled and subsequently verified due to the disruption of these control measures during the COVID-19 pandemic, causing rising trends in prospectively collected case data. Finally, in 2022, the Arequipa mass dog vaccination campaign was elongated over a 6-month period, raising concerns of rabies virus reintroduction from unvaccinated regions to those already vaccinated allowing for continued persistence of the virus. Based on metapopulation simulations, we found that with sufficient vaccination coverage, rabies elimination is still attainable with an elongated vaccination campaign. This thesis identifies strategies to more successfully control canine rabies in Arequipa, Peru as well as adds insight to rabies virus epidemiology.