World Immunization Week is shining a spotlight on a growing vaccine  debate in the United States . As measles  outbreaks return and childhood vaccination rates fall below safety thresholds, pediatricians are warning that trust in public health is eroding. Government changes to the vaccine schedule under Health Secretary Robert F. Kennedy Jr. , later overturned by a judge, have fueled uncertainty. Supporters of vaccine choice argue for parental rights, while doctors fear the consequences for