A dangerous measles outbreak has been traced to a megachurch in Texas whose leader told followers to stay away from vaccines.

Terri Pearsons, the daughter of prominent televangelist Kenneth Copeland, and the leader of Eagle Mountain International Church in Newark, Texas, has long warned followers to stay away from vaccines, promoting the idea that they cause autism. The un-vaccinated congregation was recently put in danger when a member left the country and came in contact with measles. They then returned to Texas, where they interacted with the congregation, as well as handled children in the church's on-site day-care center.

Nine children and six adults have been infected with the disease, twelve of whom were not fully vaccinated. All of the school-aged children infected were home-schooled, and didn't have to get the immunization shots needed to enter public schools. Infected people will spread the disease to 90% of the people they come in contact with.

"This is a classic example of how measles is being reintroduced," William Schaffner, a professor and infectious disease expert at Vanderbilt University School of Medicine in Nashville told USA Today, citing examples where fears of vaccines causing autism have led to measles outbreaks. "This is a sadly misinformed religious leader."

Following the outbreak, Pearsons has called on all congregants to become vaccinated.

"Our children and even adults of all ages need to be immunized now to stop the spread of measles and prevent those potential complications," She said. "The disease is only shut down when all are immunized."