Immunization critics may be more likely to rethink their attitude, if a disease outbreak occurs close to home.

That’s a key finding from a study released this week and headed by a University of Idaho professor.

The study comes as Idaho’s immunization policies come under increased political scrutiny. The state allows parents to opt their kids out of suggested immunizations, which drives down Idaho’s overall immunization rate. Idaho’s immunization opt-out numbers are among the highest in the nation.

Some parents are skeptical about vaccines for a number of reasons, including distrust of science and “media and peer group influence,” according to the researchers. But researchers tried to look at whether opinions change, in the wake of measles outbreaks.

In a nutshell, people who are skeptical about vaccines are more likely to hold to their views, the farther away they live from an outbreak. “The implication of our study is that some people base their vaccine decision-making to a considerable degree on whether or not a given disease occurs in close vicinity to their community,” said Florian Justwan, a U of I assistant professor of political science, and the leader of the study.

People who have high confidence in public health entities, such as the federal Centers for Disease Control, are likely to immunize their children, whether they live close to an outbreak or not. “Fostering public trust in institutions such as the CDC is an important objective from a public health perspective,” Justwan said.

U of I associate philosophy professor Bert Baumgaertner, University of Utah associate professor of political science Juliet Carlisle and former student researchers from the U of I College of Letters, Arts and Social Sciences contributed to the study. The journal PLOS One published the study Wednesday.