One of the biggest stars in anti-vaccination circles is scheduled to speak in Alexandria this fall at a time the U.S. is seeing the biggest measles outbreak in 25 years.

Achieve Wellness, a local chiropractic clinic, is hosting Del Bigtree, a producer of the controversial film "Vaxxed," as well as Minnesota pediatrician Dr. Bob Zajac and Michigan vaccine critic Mary Tocco at a conference at Lake Geneva Christian Center that chiropractor Jerod Ochsendorf says could draw up to 2,000.

"He's going to have a great draw for more people to come and listen," said Ochsendorf, who co-owns Achieve Wellness.

The event worries some vaccine advocates.

A third of Minnesota schools already have extremely low vaccination rates, and this conference may drop that rate further, said Karen Ernst, executive director of Voices for Vaccines and the founder of the Minnesota Childhood Immunization Coalition.

"It's alarming that he's coming to central Minnesota to sell his package of incorrect facts," she said. "It's going to result in people not vaccinating and here we are with 800 cases of measles."

Bigtree created "Vaxxed" with Andrew Wakefield, a British doctor who led a now-discredited study that vaccines cause autism. "Vaxxed," according to its website, is about an alleged coverup of a vaccine/autism link by the U.S. Centers for Disease Control and Prevention. It was pulled from the Tribeca Film Festival in 2016 but debuted at a lesser-known festival that same year. Bigtree also hosts a YouTube channel about vaccines that has 45,000 subscribers.

Zajac is an Eden Prairie pediatrician who says he was not extensively trained in vaccines as a student and who has seen patients he believes were injured by vaccines. Tocco describes herself as an "independent vaccine investigator," public speaker and producer of two DVDs about vaccine risks.

Ochsendorf said he is organizing the conference in order to provide information about vaccines to parents facing vaccination decisions about their children and adults deciding whether to get a shot. People might not know that vaccines can contain formaldehyde, thimoseral or aluminum, or that they can report harm their children suffer from vaccinations, he said.

"People need to know what's in a vaccine," he said. "We all think that vaccines are safe, but are they safe?"

Douglas County parents apparently think so. In this county, nearly 95 percent of kindergarteners are fully vaccinated, according to the Minnesota Department of Education.

"It's a norm in this community to be well-vaccinated," said Horizon Public Health director Ann Stehn. "They work. They're highly tested and researched."

Not only are vaccines safe, she said, but they prevent diseases like measles, a highly-contagious disease that can land victims in the hospital and can, in rare cases, prove fatal. From Jan. 1 to May 17, there have been 880 cases of measles in 24 states, the greatest number of cases reported in the U.S. since 1994 and since measles was declared eliminated in 2000, the CDC reports.

"We look at vaccination as one of the major public health achievements of the last century," Stehn said. "They're a key reason why our life expectancy is risen."

But not everyone can tolerate vaccines. Ochsendorf points out that the federal government has paid out $4 billion to those who proved in court that they had been injured by vaccines. The government runs the National Vaccine Injury Compensation Program, and the Health Resources and Services Administration reports it has compensated 6,551 people, or about one person for every 1 million doses of vaccine that were distributed.

Ochsendorf says his interest in vaccines stems from his chiropractic work, which focuses on chemical, emotional and physical stressors to the body. He considers vaccines to be a chemical stressor akin to food colorings, dyes and pesticides, and is concerned that toxins can accumulate over time in our bodies and cause health issues.

He also doubts their effectiveness, saying that many diseases such as polio were declining in the U.S. before vaccines because of improved sanitation and cleaner water.

And he points out that for all the fuss over measles, measles-related deaths in the U.S. are extremely uncommon. The CDC reports the last death was in 2015, although Ochsendorf believes it was much earlier than that.

He would like to see the CDC become more transparent about its findings, such as posting more details about the strains of measles at fault in outbreaks. He believes measles can spread from the anti-vaccine shot itself.

Although Ochsendorf calls the conference an informational session and says he isn't anti-vaccination, he also is not bringing in proponents of vaccines, as he feels that the public has already heard that side.

His goal, he said, is to "help parents become more informed and more educated. It's not to tell parents not to vaccinate. It's just to provide more information about this subject. Parents are caring and loving people and they want to do the best thing for their children."

Ernst, the vaccine advocate, tracks the speakers who are coming to Alexandria.

While they might earnestly believe they are correct, she said they play to those willing to accept conspiracy thinking. They argue that government agencies and other organizations are suppressing the truth about vaccines, despite the many studies that have been done around the globe showing no link between vaccines and diseases like autism.

For that to be true, Ernst said, "you'd have to have millions of doctors and government officials are who either really cruel and keeping it all secret or are really dumb. There is a lot of mistrust of government and of expertise."

Ernst and Ochsendorf agreed on one point-that Americans are living in a time of great distrust of each other.

Ernst said Bigtree has spoken in Minnesota before, but in the Twin Cities, where his event was dwarfed by other events.

"I'm concerned about them showing up in Alexandria," she said. "It's a big venue in a small community."