President Donald Trump has signed an executive order calling for revamped childhood vaccine recommendations that promote his long-held belief that certain shots should be spaced out into separate medical visits. The order recommends separating the measles, mumps and rubella (MMR) vaccine into three different shots administered in separate visits, and directs the nation’s health department to improve vaccine research. States have the authority to require vaccinations for schoolchildren. Meanwhile, Iran says it will not reopen the Strait of Hormuz until the United States lifts its blockade on the strait, pays compensation, lifts economic sanctions and releases Iran’s frozen assets.