Texas health officials haven’t changed their minds — or their positions — on childhood immunizations. Get your children vaccinated, they say. “I personally think that vaccinations are one of the greatest public health triumphs of human history,” said Witold Migala, a professor of epidemiology at the University of North Texas Health Science Center in Fort Worth. “I’ve worked extensively on polio immunization. Polio is a disease which only exists in the human pool.