According to state data, the number of Texans forgoing child vaccinations has tripled in the last six years. In all, more than 38,000 Texas and 250 local students were granted waivers exempting them from vaccinations required by the state during the 2013-14 school year. The 250 in Jefferson, Hardin and Orange counties is less than 1 percent of the student population in each of the counties, state data shows. On average, it would take at least 10 percent of the population to avoid vaccination to actually spread a disease like the measles, according to Dr. Richard Rupp, director of UTMB's Office of Clinical Trials.