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  • Season of death, pathogen persistence and wildlife behaviour alter number of anthrax secondary infections from environmental reservoirs
Title: Season of death, pathogen persistence and wildlife behaviour alter number of anthrax secondary infections from environmental reservoirs
An important part of infectious disease management is predicting factors that influence disease outbreaks, such asR, the number of secondary infections arising from an infected individual. EstimatingRis particularly challenging for environmentally transmitted pathogens given time lags between cases and subsequent infections. Here, we calculatedRforBacillus anthracisinfections arising from anthrax carcass sites in Etosha National Park, Namibia. Combining host behavioural data, pathogen concentrations and simulation models, we show thatRis spatially and temporally variable, driven by spore concentrations at death, host visitation rates and early preference for foraging at infectious sites. While spores were detected up to a decade after death, most secondary infections occurred within 2 years. Transmission simulations under scenarios combining site infectiousness and host exposure risk under different environmental conditions led to dramatically different outbreak dynamics, from pathogen extinction (R< 1) to explosive outbreaks (R> 10). These transmission heterogeneities may explain variation in anthrax outbreak dynamics observed globally, and more generally, the critical importance of environmental variation underlying host–pathogen interactions. Notably, our approach allowed us to estimate the lethal dose of a highly virulent pathogen non-invasively from observational studies and epidemiological data, useful when experiments on wildlife are undesirable or impractical.  more » « less
Award ID(s):
2106221
PAR ID:
10528008
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Proceedings of the Royal Society B: Biological Sciences
Date Published:
Journal Name:
Proceedings of the Royal Society B: Biological Sciences
Volume:
291
Issue:
2016
ISSN:
0962-8452
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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