skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.
Attention:The NSF Public Access Repository (NSF-PAR) system and access will be unavailable from 7:00 AM ET to 7:30 AM ET on Friday, April 24 due to maintenance. We apologize for the inconvenience.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


Title: Exploring the Effects of Prescribed Fire on Tick Spread and Propagation in a Spatial Setting
Lyme disease is one of the most prominent tick-borne diseases in the United States, and prevalence of the disease has been steadily increasing over the past several decades due to a number of factors, including climate change. Methods for control of the disease have been considered, one of which is prescribed burning. In this paper, the effects of prescribed burns on the abundance of ticks present in a spatial domain are assessed. A spatial stage-structured tick-host model with an impulsive differential equation system is developed to simulate the effect that controlled burning has on tick populations. Subsequently, a global sensitivity analysis is performed to evaluate the effect of various model parameters on the prevalence of infectious nymphs. Results indicate that while ticks can recover relatively quickly following a burn, yearly, high-intensity prescribed burns can reduce the prevalence of ticks in and around the area that is burned. The use of prescribed burns in preventing the establishment of ticks into new areas is also explored, and it is observed that frequent burning can slow establishment considerably.  more » « less
Award ID(s):
1920946
PAR ID:
10321322
Author(s) / Creator(s):
; ;
Editor(s):
Supriatna, Asep Kuswandi
Date Published:
Journal Name:
Computational and Mathematical Methods in Medicine
Volume:
2022
ISSN:
1748-670X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; (, Canadian Journal of Infectious Diseases and Medical Microbiology)
    Di Luca, Marco (Ed.)
    Recently, tick-borne illnesses have been trending upward and are an increasing source of risk to people’s health in the United States. This is due to range expansion in tick habitats as a result of climate change. Thus, it is imperative to find a practical and cost-efficient way of managing tick populations. Prescribed burns are a common form of land management that can be cost-efficient if properly managed and can be applied across large amounts of land. In this study, we present a compartmental model for ticks carrying Lyme disease and uniquely incorporate the effects of prescribed fire using an impulsive system to investigate the effects of prescribed fire intensity (high and low) and the duration between burns. Our study found that fire intensity has a larger impact in reducing tick population than the frequency between burns. Furthermore, burning at high intensity is preferable to burning at low intensity whenever possible, although high-intensity burns may be unrealistic due to environmental factors. Annual burns resulted in the most significant reduction in infectious nymphs, which are the primary carriers of Lyme disease. 
    more » « less
  2. ; ; ; ; (, Proceedings of the Royal Society B: Biological Sciences)
    Hard-bodied ticks (Acari: Ixodidae) pose a major public health threat, transmitting multiple pathogens among humans and wildlife worldwide. Research has investigated how anthropogenic land use change impacts tick density and infection prevalence in temperate forests, including the effects of active forest management practices like prescribed burning, invasive vegetation removal and timber harvesting. However, studies’ results are inconsistent and seemingly context-dependent, making it difficult for land managers, landowners and policy makers to identify whether management addresses the public health concern. We performed a systematic review and meta-analysis and documented a net decrease in tick density correlating with prescribed burns and invasive vegetation removal, but no effect on tick infection prevalence. Our review of a substantially smaller number of timber harvesting-focused studies showed the same pattern. Through a systematic literature review, we explored potential causal pathways between these management practices and lower tick density, including microclimate- and host-driven mechanisms. We recommend that future research explore mechanisms for tick infection prevalence and, for prescribed burn studies, employ standardized measurements of burn intensity and consider long-term effects post-burn. 
    more » « less
  3. ; ; ; (, Ecosphere)
    Abstract Changing climate has driven shifts in species phenology, influencing a range of ecological interactions from plant–pollinator to consumer–resource. Phenological changes in host–parasite systems have implications for pathogen transmission dynamics. The seasonal timing, or phenology, of peak larval and nymphal tick abundance is an important driver of tick‐borne pathogen prevalence through its effect on cohort‐to‐cohort transmission. Tick phenology is tightly linked to climatic factors such as temperature and humidity. Thus, variation in climate within and across regions could lead to differences in phenological patterns. These differences may explain regional variation in tick‐borne pathogen prevalence of the Lyme disease‐causingBorreliabacteria in vector populations in the United States. For example, one factor thought to contribute to high Lyme disease prevalence in ticks in the eastern United States is the asynchronous phenology of ticks there, where potentially infected nymphal ticks emerge earlier in the season than uninfected larval ticks. This allows the infected nymphal ticks to transmit the pathogen to hosts that are subsequently fed upon by the next generation of larval ticks. In contrast, in the western United States where Lyme disease prevalence is generally much lower, tick phenology is thought to be more synchronous with uninfected larvae emerging slightly before, or at the same time as, potentially infected nymphs, reducing horizontal transmission potential. Sampling larval and nymphal ticks, and their host‐feeding phenology, both across large spatial gradients and through time, is challenging, which hampers attempts to conduct detailed studies of phenology to link it with pathogen prevalence. In this study, we demonstrate through intensive within‐season sampling that the relative abundance and seasonality of larval and nymphal ticks are highly variable along a latitudinal gradient and likely reflect the variable climate in the far western United States with potential consequences for pathogen transmission. We find that feeding patterns were variable and synchronous feeding of juvenile ticks on key blood meal hosts was associated with mean temperature. By characterizing within‐season phenological patterns of the Lyme disease vector throughout a climatically heterogeneous region, we can begin to identify areas with high potential for tick‐borne disease risk and underlying mechanisms at a finer scale. 
    more » « less
  4. ; ; (, Ecosphere)
    Abstract Biodiversity has been linked to reduced disease transmission through the dilution effect process. Traditional ecological measures of biological diversity, such as species richness, are most commonly used to test for the dilution effect. However, such metrics of species diversity do not consider the evolutionary relationship between species, which has important implications for host immune processes and disease transmission. Phylogenetic diversity incorporates the evolutionary relationships of a wildlife community. Host reservoir competency is partly determined by their capacity to mount effective immune responses, which may be phylogenetically determined. As a result, phylogenetic diversity may be a better metric to evaluate the relationship between host diversity and disease transmission, given that closely related species may have more similar pathogen competencies than distantly related ones. Few studies have examined the relationship between phylogenetic diversity and disease transmission, particularly in vector‐borne transmission systems. This study seeks to quantify phylogenetic diversity in the western United States Lyme disease system, where the causal agentBorrelia burgdorferiis vectored by the western black‐legged tick,Ixodes pacificus.We empirically measured mammalian diversity and tick data over seven years. We collected data on ticks, host community, and infection prevalence withBorrelia burgdorferiand constructed generalized linear mixed‐effect models to evaluate the utility of phylogenetic diversity in predicting the prevalence of a tick‐borne pathogen. We found that phylogenetic diversity metrics improved our disease prediction models. Predictions of the overall density and infection prevalence of ticks were improved by the addition of phylogenetic metrics, whereas the density of infected nymphs was solely predicted by a phylogenetic metric over traditional species diversity or richness. Our study found that phylogenetic diversity improves statistical predictions of the Lyme disease pathogen and entomological risk in the western United States and may be informative in other contexts and systems as well. 
    more » « less
  5. ; ; ; ; ; (, EcoEvoRxiv)
    Under global change, plant invasions may alter tick-borne disease (TBD) transmission. The direction and magnitude of changes in TBD risk resulting from invasions remain poorly understood because research has often been species-specific or insufficient to quantify mechanisms. In this overview, we describe how invasive plant functional traits can mediate microclimates, how tick survival and abundance vary under altered environmental conditions created by invasive plants, and how invasive plants can impact blood meal host activity and pathogen prevalence. These findings are synthesized within a One Health framework that considers climate, landscape, and disturbance to ultimately predict TBD risk. Finally, we discuss range expansion of ticks and pathogens, spatial and temporal research scales, and modeling approaches for predicting TBD risk amidst global change. We highlight how plant invasions and climate change can impact ticks, hosts, and pathogens, and we identify research needs to improve models of TBDs in a changing world. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Text Encoded Conversion
  • XML
  • Save / Share this Record
  • Send to Email