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Wildlife species are often heavily parasitized by multiple infections simultaneously. Yet research on sylvatic transmission cycles, tend to focus on host interactions with a single parasite and neglects the influence of co- infections by other pathogens and parasites. Co-infections between macro-parasites and micro-parasites can alter mechanisms that regulate pathogenesis and are important for understanding disease emergence and dy- namics. Wildlife rodent hosts in the Lyme disease system are infected with macro-parasites (i.e., ticks and hel- minths) and micro-parasites (i.e., Borrelia spp.), however, there has not been a study that investigates the interaction of all three parasites (i.e., I. pacificus, Borrelia spp., and helminths) and how these co-infections impact prevalence of micro-parasites. We live-trapped rodents in ten sites in northern California to collect feces, blood, ear tissue, and attached ticks. These samples were used to test for infection status of Borrelia species (i.e., micro- parasite), and describe the burden of ticks and helminths (i.e., macro-parasites). We found that some rodent hosts were co-infected with all three parasites, however, the burden or presence of concurrent macro-parasites were not associated with Borrelia infections. For macro-parasites, we found that tick burdens were positively associ- ated with rodent Shannon diversity while negatively associated with predator diversity, whereas helminth burdens were not significantly associated with any host community metric. Ticks and tick-borne pathogens are associated with rodent host diversity, predator diversity, and abiotic factors. However, it is still unknown what factors helminths are associated with on the community level. Understanding the mechanisms that influence co- infections of multiple types of parasites within and across hosts is an increasingly critical component of characterizing zoonotic disease transmission and maintenance.
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Intercontinental comparisons of subterranean host–parasite communities using bipartite network analyses
Abstract Rodents living in a subterranean ecotope face a unique combination of evolutionary and ecological pressures and while host species evolution may be driven by the selective pressure from the parasites they harbour, the parasites may be responding to the selective pressures of the host. Here, we obtained all available subterranean rodent host–parasite records from the literature and integrated these data by utilizing a bipartite network analysis to determine multiple critical parameters to quantify and measure the structure and interactions of the organisms present in host–parasite communities. A total of 163 species of subterranean rodent hosts, 174 parasite species and 282 interactions were used to create 4 networks with data well-represented from all habitable continents. The results show that there was no single species of parasite that infects subterranean rodents throughout all zoogeographical regions. Nevertheless, species representing the generaEimeriaandTrichuriswere common across all communities of subterranean rodents studied. Based on our analysis of host–parasite interactions across all communities studied, the parasite linkages show that community connectance (due to climate change or other anthropogenic factors) appears to show degraded linkages in both the Nearctic and Ethiopian regions: in this case parasites are acting as bell-weather probes signalling the loss of biodiversity.
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- Award ID(s):
- 1756397
- PAR ID:
- 10655607
- Publisher / Repository:
- Cambridge University Press
- Date Published:
- Journal Name:
- Parasitology
- Volume:
- 150
- Issue:
- 5
- ISSN:
- 0031-1820
- Page Range / eLocation ID:
- 446 to 454
- Subject(s) / Keyword(s):
- Cestoda diversity endoparasite Nemata network subterranean rodents, Bipartite network analysis, subterranean rodents, Bathyergidae, Chrysochloridae, Muridae), Ctenomyidae, Octodontidae, Cricetidae, Spalacidae, Geomyidae
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1017/S0031182023000148
