Marta L Wayne1, Gabriela M Blohm2, Mollie E Brooks2, Kerry L Regan3, Brennin Y Brown2, Michael Barfield2, Robert D Holt4, Benjamin M Bolker5. 1. Department of Biology, University of Florida, Gainesville, Florida, USA ; Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA ; UF Genetics Institute, University of Florida, Gainesville, Florida, USA. 2. Department of Biology, University of Florida, Gainesville, Florida, USA. 3. Department of Biology, University of Florida, Gainesville, Florida, USA ; Department of Biological Sciences, University of Notre Dame, South Bend, Indiana, USA. 4. Department of Biology, University of Florida, Gainesville, Florida, USA ; Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA. 5. Department of Biology, University of Florida, Gainesville, Florida, USA ; Department of Mathematics, McMaster University, Hamilton, Ontario, Canada.
Abstract
QUESTION: How do vertically transmitted parasites persist? ORGANISMS: Drosophila melanogaster (host) and sigma virus (parasite). FIELD SITE: Peach stands in northern Georgia, USA, on a transect between Macon and Athens. EMPIRICAL METHODS: We estimated prevalence in the field. We also estimated male and female transmission in the laboratory, using field-collected animals as parents. We further quantified patrilineal (father to son) transmission in the laboratory, and estimated cost of infection (virulence) by quantifying decreased egg production of infected flies. MATHEMATICAL METHODS: Discrete-time, deterministic models for prevalence; analysis of stability of disease-free and endemic equilibria; numerical computation of equilibria based on empirical estimates. KEY ASSUMPTIONS: Random mating, discrete generations, cost of infection to females only. PREDICTIONS AND CONCLUSIONS: The model allows persistence under parameter estimates obtained for this population. Uncertainty in parameters leads to wide confidence intervals on the predicted prevalence, which may be systematically underestimated due to Jensen's inequality. Male transmission is required for persistence, and multiple generations of strictly patrilineal transmission are possible in the laboratory, albeit with decreasing transmission efficiency.
QUESTION: How do vertically transmitted parasites persist? ORGANISMS: Drosophila melanogaster (host) and sigma virus (parasite). FIELD SITE: Peach stands in northern Georgia, USA, on a transect between Macon and Athens. EMPIRICAL METHODS: We estimated prevalence in the field. We also estimated male and female transmission in the laboratory, using field-collected animals as parents. We further quantified patrilineal (father to son) transmission in the laboratory, and estimated cost of infection (virulence) by quantifying decreased egg production of infected flies. MATHEMATICAL METHODS: Discrete-time, deterministic models for prevalence; analysis of stability of disease-free and endemic equilibria; numerical computation of equilibria based on empirical estimates. KEY ASSUMPTIONS: Random mating, discrete generations, cost of infection to females only. PREDICTIONS AND CONCLUSIONS: The model allows persistence under parameter estimates obtained for this population. Uncertainty in parameters leads to wide confidence intervals on the predicted prevalence, which may be systematically underestimated due to Jensen's inequality. Male transmission is required for persistence, and multiple generations of strictly patrilineal transmission are possible in the laboratory, albeit with decreasing transmission efficiency.
Authors: Marta L Wayne; Marina Telonis-Scott; Lisa M Bono; Larry Harshman; Artyom Kopp; Sergey V Nuzhdin; Lauren M McIntyre Journal: Proc Natl Acad Sci U S A Date: 2007-11-14 Impact factor: 11.205
Authors: Helen Piontkivska; Luis F Matos; Sinu Paul; Brian Scharfenberg; William G Farmerie; Michael M Miyamoto; Marta L Wayne Journal: Genome Biol Evol Date: 2016-10-05 Impact factor: 3.416