Predicting advancing wavefronts of vampire bat rabies
Our latest set of analyses of data from the Ministry of Agriculture of Peru, together with our own questionnaire data, show that rabies continues to spread to the fringes of the vampire bat distribution in surprisingly constant and predictable wave-like expansions. The ability to forecast when and where rabies will appear next provides a tantalizing opportunity to develop interventions like vaccination of humans and livestock (or perhaps even the bats themselves) before rabies arrives to new regions. Hopefully this puts us one step closer to preventative rather than reactive management of vampire bat rabies.
Forecasting traveling waves of vampire bat rabies using simple landscape-adjusted linear regression models. Pie charts show the percentages of farms reporting bat bites (green), indicating the presence of vampire bats ahead of wavefronts. Blue and red points are the locations of rabies outbreaks in livestock.
The paper is published free online at Proceedings of the Royal Society B.
Julio and I also wrote a short piece in The Conversation describing the results of this analysis against a broader context of vampire bat rabies in Latin America.
Benavides, J., Valderrama, W., & Streicker, D.G. Spatial expansions and travelling waves of rabies in vampire bats (2016) Proceedings of the Royal Society B. DOI: 10.1098/rspb.2016.0328
Does rabies really need to evolve in new hosts?
Mollentze, N., Biek, R., & Streicker D.G. (2014) The role of viral evolution in rabies host shifts and emergence. Current Opinion in Virology doi: 10.1016/j.coviro.2014.07.004
Abstract: Despite its ability to infect all mammals, Rabies virus persists in numerous species-specific cycles that rarely sustain transmission in alternative species. The determinants of these species-associations and the adaptive significance of genetic divergence between host-associated viruses are poorly understood. One explanation is that epidemiological separation between reservoirs causes neutral genetic differentiation. Indeed, recent studies attributed host shifts to ecological factors and selection of ‘preadapted’ viral variants from the existing viral community. However, phenotypic differences between isolates and broad scale comparative and molecular evolutionary analyses indicate multiple barriers that Rabies virus must overcome through adaptation. This review assesses various lines of evidence and proposes a synthetic hypothesis for the respective roles of ecology and evolution in Rabies virus host shifts.