Trump's vaccine plan would require millions of individual shots last used decades ago

A plan proposed by Donald Trump calls for separating combination vaccines, such as MMR, into individual shots and spacing out vaccinations, which would require drugmakers to revive unused vaccine formulations and build new manufacturing plants. Public health experts argue that this policy lacks scientific basis and would impose significant financial and logistical challenges on parents and providers. Implementing the changes could take years and involve massive research and development by pharmaceutical companies.