President Donald Trump's vaccine plan faces significant financial and logistical hurdles. Drugmakers must develop new manufacturing processes and conduct extensive clinical studies. Separating vaccines could lead to more appointments and increased costs for families. Public health experts question the scientific basis for the proposed changes. States retain authority to mandate school vaccinations, potentially disregarding the order.

President Donald Trump will sign an executive order calling for spacing out childhood vaccines into separate medical visits and splitting the combined measles, mumps and rubella…

The executive order would call for states to reconsider guidance for vaccine requirements for school