By Chad Terhune (Reuters) -As a measles outbreak spreads across West Texas, Dr. Ana Montanez is fighting an uphill battle to convince some parents that vitamin A - touted by vaccine critics as effective against the highly contagious virus - will not protect their children.

CLEVELAND, Ohio — The measles outbreak in Texas and New Mexico has resulted in a second death, leaving many Ohioans wondering if they and their families are protected against the dangerous virus and if — as federal health official Robert F. Kennedy Jr. has stated — vitamin A prevents measles deaths.