Some key public health figures are taking an extraordinary step to try to shore up U.S. vaccination policy, feared to be under threat from health secretary Robert F. Kennedy Jr.

Harris County Public Health is promoting National Infant Immunization Week by highlighting the importance of vaccinations for children under two to protect them from vaccine-preventable diseases.

Health officials are particularly concerned as nearly 25% of Montcalm County children under 3 years old have not received their first dose of the measles, mumps, and rubella (MMR) vaccine.