FILE – In this April 11, 2005, file photo, Dr. Jonathan D. Salk, left, son of Dr. Jonas Salk, Anna Eleanor Roosevelt, granddaughter of President Franklin Delano Roosevelt and Benjamin C. Bradlee, former editor of The Washington Post and a child polio patient, mark the 50th anniversary of the polio vaccine's April 1955 introduction while visiting an exhibit titled "Whatever Happened to Polio?" at the Smithsonian Institution's National Museum of American History in Washington. Jonathan Salk, who helped his father complete the 1981 book "World Population and Human Values: A New Reality," has updated the book with new data, graphics and a redesign, coinciding with the 62nd anniversary in 2017 of the polio vaccine's introduction. (AP Photo/Haraz Ghanbari, File)