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Abstract The drylands vesper mouse (Calomys musculinus)is the primary host forJunin mammarenavirus(JUNV), the etiological agent of Argentine hemorrhagic fever in humans. We assessed the potential distribution ofC. musculinusand identified disease transmission hotspots under current climatic conditions and projected future scenarios, including severe (Representative Concentration Pathway 8.5) and intermediate (Representative Concentration Pathway 4.5) climate change scenarios in 2050 and 2070. Utilizing tree-based machine learning algorithms, we modeledC. musculinusdistribution by incorporating bioclimatic and landscape predictors. The model showed strong performance, achievingF-scores between 80.22 and 83.09%. Key predictors indicated thatC. musculinusprefers warm temperatures, moderate annual precipitation, low precipitation variability, and low pasture coverage. Under the severe climate change scenario, suitable areas for the rodent and hotspots for potential disease decreased. The intermediate scenario showed an expansion inC. musculinusdistribution alongside increased potential hotspot zones. Despite the complexity of ecological systems and the limitations of the model, our findings offer a framework for preventive measures and ecological studies in regions prone to the expansion ofC. musculinusand in hotspots for disease transmission driven by climate change.
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Modelling the distribution in Hawaii of Angiostrongylus cantonensis (rat lungworm) in its gastropod hosts
Abstract Angiostrongylus cantonensis (rat lungworm), a parasitic nematode, is expanding its distribution. Human infection, known as angiostrongyliasis, may manifest as eosinophilic meningitis, an emerging infectious disease. The range and incidence of this disease are expanding throughout the tropics and subtropics. Recently, the Hawaiian Islands have experienced an increase in reported cases. This study addresses factors affecting the parasite's distribution and projects its potential future distribution, using Hawaii as a model for its global expansion. Specimens of 37 snail species from the Hawaiian Islands were screened for the parasite using PCR. It was present on five of the six largest islands. The data were used to generate habitat suitability models for A. cantonensis , based on temperature and precipitation, to predict its potential further spread within the archipelago. The best current climate model predicted suitable habitat on all islands, with greater suitability in regions with higher precipitation and temperatures. Projections under climate change (to 2100) indicated increased suitability in regions with estimated increased precipitation and temperatures, suitable habitat occurring increasingly at higher elevations. Analogously, climate change could facilitate the spread of A. cantonensis from its current tropical/subtropical range into more temperate regions of the world, as is beginning to be seen in the continental USA.
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- PAR ID:
- 10089465
- Date Published:
- Journal Name:
- Parasitology
- Volume:
- 146
- Issue:
- 1
- ISSN:
- 0031-1820
- Page Range / eLocation ID:
- 42 to 49
- 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/S0031182018001026
