A new publication out today in PLoS Neglected Tropical Diseases, led by Assistant Professor Raina Plowright (Montana State University), with Hamish McCallum, Alison Peel and others, outlines an agenda to disentangle the mechanisms driving pulses of viral excretion from bat populations.
The figure on the right (source) illustrates within-host dynamics for three working hypotheses about the dynamics of emerging viruses within bats presented within our publication. Red pulses represent viral load within an individual, and blue represents an individual bat's immune response to infection. In (A), following an initial acute infection, the virus clears completely and bats remain refractory to infection (susceptible-infectious-recovered [SIR]). In (B), The virus clears completely, but the bats’ immune response wanes over time, allowing individuals to be reinfected (susceptible-infectious-recovered-susceptible [SIRS]). In (C), Following the acute phase of infection, a chronic infection remains, or the infection is latent and then reactivated (susceptible-infectious-latent-infectious [SILI]).
The alternative hypotheses proposed can yield similar patterns in epidemiological surveys, but strategies to predict or manage spillover risk resulting from each scenario will be different. We explore this, with examples provided for Hendra virus and other bat pathogens, but the concepts are applicable across a wide range of systems.
Plowright, R. K., A. J. Peel, D. G. Streicker, A. Gilbert, H. McCallum, J. L. N. Wood, M. L. Baker, and O. Restif. 2016. Transmission or within-host dynamics driving pulses of zoonotic viruses in reservoir-host populations. 1 pp. PLoS Neglected Tropical Diseases 10: e0004796. (link)