DOI: 10.5061/dryad.ttdz08m62
title: Data from: Host disease tolerance predicts transmission probability for a songbird pathogen

description: Disease tolerance reduces the per-pathogen fitness costs of infection for
 hosts and is an important component of host adaptation to pathogens.
 However, how disease tolerance affects host transmission potential is not
 well understood, especially because there are many potential mechanisms
 that facilitate host tolerance. For example, tissue-specific host
 tolerance leads to the reduction of host pathology, regardless of pathogen
 load. Hosts may also exhibit behavioral tolerance, where normal behaviors
 are maintained even while harboring high pathogen loads. Here, we examined
 the impacts that tissue-specific and behavioral tolerance have on
 transmission in house finches (Haemorhous mexicanus) infected with a
 common and highly virulent bacterial pathogen, Mycoplasma gallisepticum
 (MG). MG causes conjunctivitis in house finches and severely reduces
 population numbers after it arrives in a new area. Wild house finch
 populations differ in tissue-specific tolerance to MG and here we assessed
 how this variation in tolerance influences transmission success. We
 inoculated wild-captured MG-naïve individuals from two populations that
 are on the extremes of tissue-specific tolerance to MG and determined the
 likelihood of these ‘index’ individuals transmitting MG to an uninfected,
 susceptible cagemate. Higher tissue-specific tolerance results in reduced
 conjunctivitis, which is associated with decreased deposition and spread
 of MG. Thus, we predicted that individuals with high tissue-specific
 tolerance would be less likely to transmit MG. In contrast, we predicted
 that behavioral tolerance would be linked to higher transmission, as more
 tolerant individuals spent more time on a feeder shared with a susceptible
 individual despite high pathogen loads. In agreement with our prediction,
 individuals with high tissue-specific tolerance were less likely to
 transmit MG. However, there was no effect of behavioral tolerance on the
 likelihood of MG transmission. Our results highlight that it is key to
 consider how different mechanisms of tolerance affect transmission and,
 therefore, host-pathogen coevolution and epidemic dynamics.
description: # Data from: Host disease tolerance predicts transmission probability for
 a songbird pathogen
 [https://doi.org/10.5061/dryad.ttdz08m62](https://doi.org/10.5061/dryad.ttdz08m62) This dataset includes both data and code used for all analyses in the manuscript "Host disease tolerance predicts transmission probability for a songbird pathogen". This paper explores the effects of host disease tolerance on the transmission of a pathogen. ## Description of the data and file structure The Data Dictionary (Henschen et al data dictionary 20240314.csv) describes each variable (column) in the dataset (Henschen et al data 20240314) and is also reproduced below. The .R file (Henschen et al for submission 20240314.R) contains the annotated code used to analyze this dataset. The .Rproj file (Henschen et al Submission 20240314.Rproj) allows you to run all code directly if opened in R Studio. | variable | explanation | | :----------------------------------- | :---------------------------------------------------------------------------------------------------------------------------------------------- | | pop | initially infected bird's population of origin--either AL for Alabama or AZ for Arizona | | band | initially infected bird's leg band number for identification | | sex | initially infected bird's sex | | cagemate | identification (leg band number) uninitially infected bird housed with a given initially infected bird | | transmitted\_eye\_score | whether initially infected bird transmitted infection to cagemate, as assayed by eye score in cagemate | | max\_eye\_score\_dpi11\_index | initially infected bird's maximum eye score up to and including day 11 post inoculation--range is 0 to 6 | | max\_path\_load\_log10\_dpi11\_index | initially infected bird's maximum pathogen load up to and including day 11 post inoculation--transformed as log10(pathogen load + 1) | | min\_on\_feeder\_dur\_dpi11\_index | initially infected bird's minimum time spent on feeder across 30min focal observation periods up to and including day 11 post inoculation | | tts\_dpi11 | tissue specific tolerance of initially infected bird, calculated as -max\_eye\_score\_dpi11\_index/max\_path\_load\_log10\_dpi11\_index | | tbeh\_dpi11 | behavioral specific tolerance of initially infected bird, calculated as min\_on\_feeder\_dur\_dpi11\_index/max\_path\_load\_log10\_dpi11\_index | Missing data code: NA ## Code/Software All code is run in R and the available Rproj file allows you to run the code directly if opened in R Studio. The following R packages are required to run this code: tidyverse, car, RColorBrewer, and ggpubr. The code is annotated in the available .R file.