UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Environmental limits of Rift Valley fever revealed using ecoepidemiological mechanistic models

Lo Iacono, G; Cunningham, AA; Bett, B; Grace, D; Redding, DW; Wood, JLN; (2018) Environmental limits of Rift Valley fever revealed using ecoepidemiological mechanistic models. Proceedings of the National Academy of Sciences of the United States of America , 115 (31) E7448-E7456. 10.1073/pnas.1803264115. Green open access

[thumbnail of Article]
Preview
Text (Article)
Lo Iacono_PDF PNAS.pdf - Accepted Version

Download (3MB) | Preview
[thumbnail of Supporting Information]
Preview
Text (Supporting Information)
Lo Iacono_RVF Supporting information.pdf - Accepted Version

Download (11MB) | Preview

Abstract

Vector-borne diseases (VBDs) of humans and domestic animals are a significant component of the global burden of disease and a key driver of poverty. The transmission cycles of VBDs are often strongly mediated by the ecological requirements of the vectors, resulting in complex transmission dynamics, including intermittent epidemics and an unclear link between environmental conditions and disease persistence. An important broader concern is the extent to which theoretical models are reliable at forecasting VBDs; infection dynamics can be complex, and the resulting systems are highly unstable. Here, we examine these problems in detail using a case study of Rift Valley fever (RVF), a high-burden disease endemic to Africa. We develop an ecoepidemiological, compartmental, mathematical model coupled to the dynamics of ambient temperature and water availability and apply it to a realistic setting using empirical environmental data from Kenya. Importantly, we identify the range of seasonally varying ambient temperatures and water-body availability that leads to either the extinction of mosquito populations and/or RVF (nonpersistent regimens) or the establishment of long-term mosquito populations and consequently, the endemicity of the RVF infection (persistent regimens). Instabilities arise when the range of the environmental variables overlaps with the threshold of persistence. The model captures the intermittent nature of RVF occurrence, which is explained as low-level circulation under the threshold of detection, with intermittent emergence sometimes after long periods. Using the approach developed here opens up the ability to improve predictions of the emergence and behaviors of epidemics of many other important VBDs.

Type: Article
Title: Environmental limits of Rift Valley fever revealed using ecoepidemiological mechanistic models
Open access status: An open access version is available from UCL Discovery
DOI: 10.1073/pnas.1803264115
Publisher version: https://doi.org/10.1073/pnas.1803264115
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
Keywords: vector-borne, diseases, zoonosis, cross-species transmission, stability analysis, Floquet analysis
UCL classification: UCL
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences > Div of Biosciences
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Life Sciences > Div of Biosciences > Genetics, Evolution and Environment
URI: https://discovery.ucl.ac.uk/id/eprint/10050810
Downloads since deposit
163Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item