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Abstract Pathogen spillover from wildlife to humans or domestic animals requires a series of conditions to align with space and time. Comparing these conditions between times and locations where spillover does and does not occur presents opportunities to understand the factors that shape spillover risk. Bovine rabies transmitted by vampire bats was first confirmed in 1911 and has since been detected across the distribution of vampire bats. However, Uruguay is an exception. Uruguay was free of bovine rabies until 2007, despite high-cattle densities, the presence of vampire bats and a strong surveillance system. To explore why Uruguay was free of bovine rabies until recently, we review the historic literature and reconstruct the conditions that would allow rabies invasion into Uruguay. We used available historical records on the abundance of livestock and wildlife, the vampire bat distribution and occurrence of rabies outbreaks, as well as environmental modifications, to propose four alternative hypotheses to explain rabies virus emergence and spillover: bat movement, viral invasion, surveillance failure and environmental changes. While future statistical modelling efforts will be required to disentangle these hypotheses, we here show how a detailed historical analysis can be used to generate testable predictions for the conditions leading to pathogen spillover.
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Incorporating environmental heterogeneity and observation effort to predict host distribution and viral spillover from a bat reservoir
Predicting the spatial occurrence of wildlife is a major challenge for ecology and management. In Latin America, limited knowledge of the number and locations of vampire bat roosts precludes informed allocation of measures intended to prevent rabies spillover to humans and livestock. We inferred the spatial distribution of vampire bat roosts while accounting for observation effort and environmental effects by fitting a log Gaussian Cox process model to the locations of 563 roosts in three regions of Peru. Our model explained 45% of the variance in the observed roost distribution and identified environmental drivers of roost establishment. When correcting for uneven observation effort, our model estimated a total of 2340 roosts, indicating that undetected roosts (76%) exceed known roosts (24%) by threefold. Predicted hotspots of undetected roosts in rabies-free areas revealed high-risk areas for future viral incursions. Using the predicted roost distribution to inform a spatial model of rabies spillover to livestock identified areas with disproportionate underreporting and indicated a higher rabies burden than previously recognized. We provide a transferrable approach to infer the distribution of a mostly unobserved bat reservoir that can inform strategies to prevent the re-emergence of an important zoonosis.
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- Award ID(s):
- 2011069
- PAR ID:
- 10526116
- Publisher / Repository:
- The Royal Society
- Date Published:
- Journal Name:
- Proceedings of the Royal Society B: Biological Sciences
- Volume:
- 290
- Issue:
- 2011
- ISSN:
- 0962-8452
- Subject(s) / Keyword(s):
- Gaussian random field detection probability partially observed species species distribution models vampire bat rabies
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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ABSTRACT BackgroundIn Latin America, there is a high incidence of vampire bat‐transmitted rabies in cattle causing increased mortality of livestock, which heavily impacts the agricultural sector. Anticoagulants‐based control methods for the common vampire bat (Desmodus rotundus) have been employed continuously since the 1970s with various methods of application, presentations, doses and active ingredients. Studies from half a century ago still serve as a reference for the current use of anticoagulants for bat‐borne rabies control in Latin America. The objective of this study was to structurally and bibliometrically review literature on the use of anticoagulants for the control ofD. rotundusas a means of rabies control. Materials & MethodsScientific literature on the use of anticoagulant products forD. rotunduscontrol was obtained, reviewed and analysed. Articles were retrieved from Scopus and Web of Science databases. Research articles from 1971 to 2021 in Spanish, English and Portuguese were included in the review. Results were visualised using RStudio, Bibliometrix and VOSviewer. ResultsThe body of literature indicates effectiveness of up to 100% in the use of anticoagulants to induce bat mortality. The effectiveness of anticoagulants for rabies control, however, remains uncertain. No evidence was found to support or refute the use of anticoagulants for rabies control. DiscussionInstead, literature suggests that disturbing bat colonies increases rabies prevalence. This finding suggests that anticoagulants may have the opposite intended effect on rabies control and highlights the importance of further research on the practical methods for bat‐borne rabies prevention. ConclusionField experimental studies that include control groups over areas and periods that account forD. rotundusecology are needed to determine the effectiveness of anticoagulants for rabies control in livestock. In conclusion, the use of anticoagulants for rabies control is questionable.more » « less
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1098/rspb.2023.1739
