5. Plans to travel to a Yellow-Fever endemic area during the course of the study or travel to a Yellow-Fever endemic area within 30 days of screening. Subjects who have a recent travel to a Yellow Fever endemic area may screen if they have returned to the U.S. 30 or more days prior to the screening visit. Refer to the CDC Yellow Fever map for countries/regions at risk for Yellow Fever virus infection. http://www.cdc.gov/yellowfever/maps/