A colorful killer: Daphnia infected with the bacterium Spirobacillus cienkowskii exhibit unexpected color variation

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/148232/1/ecy2562-sup-0001-AppendixS1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148232/2/ecy2562_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148232/3/ecy2562.pd

An Ecological and Conservation Perspective on Advances in the Applied Virology of Zoonoses

The aim of this manuscript is to describe how modern advances in our knowledge of viruses and viral evolution can be applied to the fields of disease ecology and conservation. We review recent progress in virology and provide examples of how it is informing both empirical research in field ecology and applied conservation. We include a discussion of needed breakthroughs and ways to bridge communication gaps between the field and the lab. In an effort to foster this interdisciplinary effort, we have also included a table that lists the definitions of key terms. The importance of understanding the dynamics of zoonotic pathogens in their reservoir hosts is emphasized as a tool to both assess risk factors for spillover and to test hypotheses related to treatment and/or intervention strategies. In conclusion, we highlight the need for smart surveillance, viral discovery efforts and predictive modeling. A shift towards a predictive approach is necessary in today’s globalized society because, as the 2009 H1N1 pandemic demonstrated, identification post-emergence is often too late to prevent global spread. Integrating molecular virology and ecological techniques will allow for earlier recognition of potentially dangerous pathogens, ideally before they jump from wildlife reservoirs into human or livestock populations and cause serious public health or conservation issues

Evolutionary consequences of feedbacks between within-host competition and disease control

Lay Summary: Competition often occurs among diverse parasites within a single host, but control efforts could change its strength. We examined how the interplay between competition and control could shape the evolution of parasite traits like drug resistance and disease severity

Dataset for Wale et al. 2017 Proc R Soc B

Dataset used in the paper. Includes daily measurements of red blood cell densities and the weight of mouse hosts, as well as the density of each parasite strain. Information about units of measurements given in the sheet entitled 'Notes on Data'

Data from: A nutrient mediates intraspecific competition between rodent malaria parasites in vivo

Hosts are often infected with multiple strains of a single parasite species. Within-host competition between parasite strains can be intense and has implications for the evolution of traits that impact patient health, such as drug resistance and virulence. Yet the mechanistic basis of within-host competition is poorly understood. Here, we demonstrate that a parasite nutrient, para-aminobenzoic acid (pABA), mediates competition between a drug resistant and drug susceptible strain of the malaria parasite, Plasmodium chabaudi. We further show that increasing pABA supply to hosts infected with the resistant strain worsens disease and changes the relationship between parasite burden and pathology. Our experiments demonstrate that, even when there is profound top-down regulation (immunity), bottom-up regulation of pathogen populations can occur and that its importance may vary during an infection. The identification of resources that can be experimentally controlled opens up the opportunity to manipulate competitive interactions between parasites and hence their evolution

Figure S1: Dynamics of single infections in individual mice from A nutrient mediates intraspecific competition between rodent malaria parasites <i>in vivo</i>

Dynamics of ASpyr in mice given unsupplemented water (blue lines) or low (green lines), medium (pink lines) and high (orange lines) concentrations of pABA. Stars represent the number of parasites inoculated and the time at which they were administered; the dot the density of parasites detected in an instance when parasites were not detected the day before or after. A black asterisk indicates that the mouse was inoculated with less parasites than was intended and was excluded from all analyses

Figure S3: The impact of pABA treatment on infection size in single and mixed infections from A nutrient mediates intraspecific competition between rodent malaria parasites <i>in vivo</i>

Total density of ASpyr during the first eight days of infection, when all mice were alive, in single (filled circles) and mixed (open circles) infections. Plotted are the means and 95% confidence intervals estimated from an analysis of the data with one mouse in the low pABA treatment, which received fewer parasites than was intended (Fig. S2, cross) excluded (A) and included (B), using a model with pABA, competition and their interaction included as terms

Figure S5: The impact of pABA supplementation on the relationship between pathogen burden & disease in single and mixed infections from A nutrient mediates intraspecific competition between rodent malaria parasites <i>in vivo</i>

The relationship between parasite density and red blood cell density (A, B) and parasite density and weight (C, D) through time in mice infected with ASpyr alone (A, C) or with both ASpyr and AJ (B, D) and given unsupplemented (blue) water or supplemented with a low (green), medium (pink) and high (orange) concentration of pABA. Means and standard errors on each day, in each treatment, are connected by straight lines to form the trajectory. Numbers indicate the day of infection. Stars represent where in parasite-health space mice were on day 0. Parasite density is the sum of all parasites, irrespective of strain. n specifies the number of mice plotted

Figure S5: The impact of pABA supplementation on the relationship between pathogen burden & disease in single and mixed infections from A nutrient mediates intraspecific competition between rodent malaria parasites <i>in vivo</i>

The relationship between parasite density and red blood cell density (A, B) and parasite density and weight (C, D) through time in mice infected with ASpyr alone (A, C) or with both ASpyr and AJ (B, D) and given unsupplemented (blue) water or supplemented with a low (green), medium (pink) and high (orange) concentration of pABA. Means and standard errors on each day, in each treatment, are connected by straight lines to form the trajectory. Numbers indicate the day of infection. Stars represent where in parasite-health space mice were on day 0. Parasite density is the sum of all parasites, irrespective of strain. n specifies the number of mice plotted