Workers paint a pedestrian crossing on a street in Porlamar, Venezuela September 12, 2016. Picture taken September 12, 2016. REUTERS/Girish Gupta

WADA Investigation team member Richard McLaren attends the World Summit on Ethics and Leadership in Sports at the headquarters of FIFA in Zurich, Switzerland September 16, 2016. REUTERS/Ruben Sprich

WADA Investigation team member Richard McLaren attends the World Summit on Ethics and Leadership in Sports at the headquarters of FIFA in Zurich, Switzerland September 16, 2016. REUTERS/Ruben Sprich

WADA Investigation team member Richard McLaren attends the World Summit on Ethics and Leadership in Sports at the headquarters of FIFA in Zurich, Switzerland September 16, 2016. REUTERS/Ruben Sprich

Republican presidential nominee Donald Trump speaks to the Economic Club of New York luncheon in Manhattan, New York, U.S., September 15, 2016. REUTERS/Mike Segar

Pumpjacks and other infrastructure for producing oil dot fields outside of Watford City, North Dakota January 21, 2016. REUTERS/Andrew Cullen

Vehicles drive along the avenue in the northern border city of Mexicali, in Baja California state, Mexico June 15, 2016. REUTERS/Dave Graham

FILE PHOTO -- A general view of the Centers for Disease Control and Prevention (CDC) headquarters in Atlanta, Georgia September 30, 2014. REUTERS/Tami Chappell/File Photo