Simon AnthonySchool of Veterinary MedicineUniversity of California, Davis Angel DesaiDivision of Infectious DiseasesUniversity of California, Davis Max FarrellMRC-Centre for Virus ResearchUniversity of Glasgow Christine Kreuder JohnsonSchool of Veterinary MedicineUniversity of California, Davis Asher LeeksYale School of MedicineYale University Alison KellMolecular Genetics & MicrobiologyUniversity of New Mexico Michael LetkoPaul G. Allen School for Global HealthWashington State University Sophie LockwoodDepartment of Ecology and EvolutionUniversity of Chicago Louise H. MonclaSchool of Veterinary MedicineUniversity of Pennsylvania Stephanie SeifertPaul G. Allen School for Global HealthWashington State University Tyler StarrDepartment of BiochemistryUniversity of Utah