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1 From the Harvard Graduate School of Education, Cambridge (M. Levinson), and the Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston (M. Lipsitch) - both in Massachusetts; and the Division of Infection and Global Health Research, School of Medicine, University of St. Andrews, Fife, United Kingdom (M.C.).
1 From the Harvard Graduate School of Education, Cambridge (M. Levinson), and the Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston (M. Lipsitch) - both in Massachusetts; and the Division of Infection and Global Health Research, School of Medicine, University of St. Andrews, Fife, United Kingdom (M.C.).