Variation in relapse frequency and the transmission potential of Plasmodium vivax malaria
Loading...
Associated Records
Authors
File Licence
Editors
Date
2016-03-30
Source Title
Proceedings of the Royal Society of London. Biological Sciences
Journal Title
Journal ISSN
Volume Title
Publisher
ROYAL SOC
Melbourne Authors
Affiliation
Medical Biology (W.E.H.I.)
Document Type
Journal Article
Subject Code
Citation
White, M. T., Shirreff, G., Karl, S., Ghani, A. C. & Mueller, I. (2016). Variation in relapse frequency and the transmission potential of Plasmodium vivax malaria. Proceedings of the Royal Society B Biological Sciences, 283 (1827), pp.20160048-. https://doi.org/10.1098/rspb.2016.0048.
Access Status
Open Access
Access URL
Open Access URL
Open Access at PMC
Linked Resource URL
NHMRC Grant Code
ARC Grant Code
Description
Abstract
There is substantial variation in the relapse frequency of Plasmodium vivax malaria, with fast-relapsing strains in tropical areas, and slow-relapsing strains in temperate areas with seasonal transmission. We hypothesize that much of the phenotypic diversity in P. vivax relapses arises from selection of relapse frequency to optimize transmission potential in a given environment, in a process similar to the virulence trade-off hypothesis. We develop mathematical models of P. vivax transmission and calculate the basic reproduction number R0 to investigate how transmission potential varies with relapse frequency and seasonality. In tropical zones with year-round transmission, transmission potential is optimized at intermediate relapse frequencies of two to three months: slower-relapsing strains increase the opportunity for onward transmission to mosquitoes, but also increase the risk of being outcompeted by faster-relapsing strains. Seasonality is an important driver of relapse frequency for temperate strains, with the time to first relapse predicted to be six to nine months, coinciding with the duration between seasonal transmission peaks. We predict that there is a threshold degree of seasonality, below which fast-relapsing tropical strains are selected for, and above which slow-relapsing temperate strains dominate, providing an explanation for the observed global distribution of relapse phenotypes.