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Title: Multiple transmission routes sustain high prevalence of a virulent parasite in a butterfly host
Understanding factors that allow highly virulent parasites to reach high infection prevalence in host populations is important for managing infection risks to human and wildlife health. Multiple transmission routes have been proposed as one mechanism by which virulent pathogens can achieve high prevalence, underscoring the need to investigate this hypothesis through an integrated modelling-empirical framework. Here, we examine a harmful specialist protozoan infecting monarch butterflies that commonly reaches high prevalence (50–100%) in resident populations. We integrate field and modelling work to show that a combination of three empirically-supported transmission routes (vertical, adult transfer and environmental transmission) can produce and sustain high infection prevalence in this system. Although horizontal transmission is necessary for parasite invasion, most new infections post-establishment arise from vertical transmission. Our study predicts that multiple transmission routes, coupled with high parasite virulence, can reduce resident host abundance by up to 50%, suggesting that the protozoan could contribute to declines of North American monarchs.  more » « less
Award ID(s):
1754392 1659683
PAR ID:
10185193
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Proceedings of the Royal Society B: Biological Sciences
Volume:
286
Issue:
1910
ISSN:
0962-8452
Page Range / eLocation ID:
20191630
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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