The Centers for Disease Control and Prevention Friday announced a plan for ensuring a continuous supply of yellow fever vaccine for travelers to countries where the virus is endemic or epidemic. Supplies of the only U.S.-licensed vaccine are expected to run out soon due to recent manufacturing problems. Until domestic production of the vaccine can resume in 2018, public health officials have arranged to import a yellow fever vaccine as an investigational new drug for distribution at a limited number of sites. In 2015, about 8 million U.S. residents traveled to 42 countries in Africa and South America where the virus is endemic. While most infected people have no symptoms, about 15% will develop severe disease. CDC expects to provide updates on the vaccine shortage at https://wwwnc.cdc.gov/travel.