Pathogen Persistence in the Environment and Insect-Baculovirus Interactions: Disease-Density Thresholds, Epidemic Burnout, and Insect Outbreaks
- 1 March 2012
- journal article
- research article
- Published by University of Chicago Press in The American Naturalist
- Vol. 179 (3), E70-E96
- https://doi.org/10.1086/664488
Abstract
Classical epidemic theory focuses on directly transmitted pathogens, but many pathogens are instead transmitted when hosts encounter infectious particles. Theory has shown that for such diseases pathogen persistence time in the environment can strongly affect disease dynamics, but estimates of persistence time, and consequently tests of the theory, are extremely rare. We consider the consequences of persistence time for the dynamics of the gypsy moth baculovirus, a pathogen transmitted when larvae consume foliage contaminated with particles released from infectious cadavers. Using field-transmission experiments, we are able to estimate persistence time under natural conditions, and inserting our estimates into a standard epidemic model suggests that epidemics are often terminated by a combination of pupation and burnout rather than by burnout alone, as predicted by theory. Extending our models to allow for multiple generations, and including environmental transmission over the winter, suggests that the virus may survive over the long term even in the absence of complex persistence mechanisms, such as environmental reservoirs or covert infections. Our work suggests that estimates of persistence times can lead to a deeper understanding of environmentally transmitted pathogens and illustrates the usefulness of experiments that are closely tied to mathematical models.Keywords
This publication has 82 references indexed in Scilit:
- Transmission of Wild-Type and Recombinant HaSnpv Among Larvae ofHelicoverpa armigera(Lepidoptera: Noctuidae) on CottonEnvironmental Entomology, 2010
- Infectious Prions in Pre-Clinical Deer and Transmission of Chronic Wasting Disease Solely by Environmental ExposurePLOS ONE, 2009
- The Role of Environmental Transmission in Recurrent Avian Influenza EpidemicsPLoS Computational Biology, 2009
- The evolution of covert, silent infection as a parasite strategyProceedings. Biological sciences, 2009
- Using Mechanistic Models to Understand Synchrony in Forest Insect Populations: The North American Gypsy Moth as a Case StudyThe American Naturalist, 2008
- Phenotypic and genotypic characterisation of persistent baculovirus infections in populations of the cabbage moth (Mamestra brassicae) within the British IslesArchiv für die gesamte Virusforschung, 2005
- Spatial heterogeneity of daphniid parasitism within lakesOecologia, 2005
- Aerial Application of the Viral Enhancer Blankophor BBH with Reduced Rates of Gypsy Moth (Lepidoptera: Lymantriidae) NucleopolyhedrovirusBiological Control, 1999
- The potential role of pathogens in biological controlNature, 1989
- PERSISTENCE AND DISPERSAL OF THE NUCLEAR POLYHEDROSIS VIRUS OF NEODIPRION SERTIFER (GEOFFROY) (HYMENOPTERA: DIPRIONIDAE) IN A VIRUS-FREE LODGEPOLE PINE PLANTATION IN SWEDENThe Canadian Entomologist, 1988