Despite a promise more than a year and half ago by the National Institutes of Health to retire the vast majority of government research chimpanzees to sanctuaries, hundreds of chimps are still being held for potential medical experimentation, many of them aging and intentionally infected with HIV or hepatitis. In June 2013, the agency’s top officials pledged with great fanfare to eventually retire the chimps to habitats where they could roam more freely instead of being cooped up in corrals or cages at research facilities.