President Donald Trump signed an executive order narrowing the vaccines recommended for all U.S. children to 11 core immunizations, creating separate categories for high-risk groups and shared clinical decision-making, and calling for measles, mumps and rubella vaccination to be offered as separate shots once single-disease products become available domestically. The order directs the Department of Health and Human Services to review the timing and sequencing of childhood vaccinations and, within 90 days, develop plans for single-vaccine options, alternative adjuvants and stronger safety monitoring, while advising states to reexamine school vaccination requirements and exemptions. Trump again linked vaccines to rising autism diagnoses, a claim disputed by medical groups, and drew immediate criticism from Sen. Bill Cassidy, while products from Merck & Co Inc., GSK PLC. and Sanofi SA could be affected.