DOI: 10.5061/dryad.bs387
title: Data from: Interactions between host sex and age of exposure modify the virulence-transmission trade-off

description: The patterns of immunity conferred by host sex or age represent two
 sources of host heterogeneity that can potentially shape the evolutionary
 trajectory of disease. With each host sex or age encountered, a pathogen’s
 optimal exploitative strategy may change, leading to considerable
 variation in expression of pathogen transmission and virulence. To date,
 these host characteristics have been studied in the context of host
 fitness alone, overlooking the effects of host sex and age on the
 fundamental virulence-transmission trade-off faced by pathogens. Here we
 explicitly address the interaction of these characteristics and find that
 host sex and age at exposure to a pathogen affect age-specific patterns of
 mortality and the balance between pathogen transmission and virulence.
 When infecting age-structured male and female Daphnia magna with different
 genotypes of Pasteuria ramosa, we found that infection increased mortality
 rates across all age classes for females, whereas mortality only increased
 in the earliest age class for males. Female hosts allowed a variety of
 trade-offs between transmission and virulence to arise with each age and
 pathogen genotype. In contrast, this variation was dampened in males, with
 pathogens exhibiting declines in both virulence and transmission with
 increasing host age. Our results suggest that differences in exploitation
 potential of males and females to a pathogen can interact with host age to
 allow different virulence strategies to coexist, and illustrate the
 potential for these widespread sources of host heterogeneity to direct the
 evolution of disease in natural populations.
description: pathogen_dataData used for analysis and visualisation of infection rate, virulence, and spore production.survival_data_10Data used for analysis and visualisation of survival curves and hazard ratios for the day 10 treatment. Included are the aged-matched control cohorts. Age-matched control cohorts were created by filtering control survival data to animals which lived at least 14 days after each exposure age as this is the earliest point in which infection status can be accurately diagnosed.survival_data_20Data used for analysis and visualisation of survival curves and hazard ratios for the day 20 treatment. Included are the aged-matched control cohorts. Age-matched control cohorts were created by filtering control survival data to animals which lived at least 14 days after each exposure age as this is the earliest point in which infection status can be accurately diagnosed.survival_data_30Data used for analysis and visualisation of survival curves and hazard ratios for the day 30 treatment. Included are the aged-matched control cohorts. Age-matched control cohorts were created by filtering control survival data to animals which lived at least 14 days after each exposure age as this is the earliest point in which infection status can be accurately diagnosed.survival_data_40Data used for analysis and visualisation of survival curves and hazard ratios for the day 40 treatment. Included are the aged-matched control cohorts. Age-matched control cohorts were created by filtering control survival data to animals which lived at least 14 days after each exposure age as this is the earliest point in which infection status can be accurately diagnosed.