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Abstract Anthropogenic land use change has led to considerable biodiversity loss, affecting ecosystem functions with unresolved consequences for zoonotic disease transmission. Functional diversity is understudied but potentially important for understanding the role of biodiversity because many zoonotic disease systems are maintained by species with different roles in disease transmission. Here, we explore how functional groups and pathogen genetic diversity influence transmission and human disease risk within the Lyme disease system. Our field and molecular ecology study examined ticks and vertebrates across a fragmented landscape and evaluated several metrics of disease risk. For predicting vector and infected vector density, rodent host richness had a positive effect and was most important, but vector infection prevalence was best predicted by rodent and predator richness together, reflecting how indirect effects may alter tick–host interactions and disease risk. These results indicate that examining species richness generally may obscure important interactions driven by richness within functional groups. Pathogen genotype richness was best predicted by overall vertebrate richness, providing support for the multiple niche polymorphism hypothesis. Our study offers an important perspective on the relationship between biodiversity and disease risk, suggesting that richness within functional groups may offer more nuanced insight into pathogen transmission dynamics than overall biodiversity.
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Functional traits explain waterbirds' host status, subtype richness, and community‐level infection risk for avian influenza
Abstract Species functional traits can influence pathogen transmission processes, and consequently affect species' host status, pathogen diversity, and community‐level infection risk. We here investigated, for 143 European waterbird species, effects of functional traits on host status and pathogen diversity (subtype richness) for avian influenza virus at species level. We then explored the association between functional diversity and HPAI H5Nx occurrence at the community level for 2016/17 and 2021/22 epidemics in Europe. We found that both host status and subtype richness were shaped by several traits, such as diet guild and dispersal ability, and that the community‐weighted means of these traits were also correlated with community‐level risk of H5Nx occurrence. Moreover, functional divergence was negatively associated with H5Nx occurrence, indicating that functional diversity can reduce infection risk. Our findings highlight the value of integrating trait‐based ecology into the framework of diversity–disease relationship, and provide new insights for HPAI prediction and prevention.
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- Award ID(s):
- 2213854
- PAR ID:
- 10509841
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Ecology Letters
- Volume:
- 26
- Issue:
- 10
- ISSN:
- 1461-023X
- Page Range / eLocation ID:
- 1780 to 1791
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1111/ele.14294
