A bill to make it easier for Iowa families to opt their children out of vaccinations stalled in a Senate subcommittee Tuesday, after senators heard from dozens of parents and medical professionals.

A small Statehouse meeting room was packed with people on both sides of the issue. The bill would have allowed parents to gain exemptions to required childhood vaccinations if the shots conflicted with "conscientiously held beliefs." Iowans already can gain vaccination exemptions for medical reasons, such as if a child is allergic to a shot, or for religious reasons, which need not be specified.

The bill was voted down, 2-1, by the subcommittee after about 40 minutes of testimony.

Vaccinations are broadly supported by medical leaders, who say they provide important protection from diseases that once rampaged through the population, leaving some children dead or disabled.

Des Moines pediatrician Nathan Boonstra pointed to recent outbreaks of measles in the northeastern and northwestern United States, which broke out among children who had not been vaccinated against the disease. "We don't really want to put out a welcome sign to measles in the Midwest," he told the senators.

Boonstra said he often takes care of fragile children who have immune problems that prevent them from getting vaccinations. They should not be exposed to others who have been unvaccinated because of unfounded fears of the shots, he said. "These children deserve to be in the safest environment possible," he said.

Many of the hearing participants belong to a group called "Informed Choice Iowa," which questions the safety of the dozens of vaccinations children are required to have in order to attend Iowa schools. Several parents held sleeping babies or toddlers in the steamy hearing room or in an overflow crowd in the hall.

Shanda Burke of Altoona, who is president of the group, disputed medical establishment claims that vaccinations are safe and keep children healthy. She said parents should have the right to choose what to do for their kids. "And those that do make the decision not to vaccinate have made that choice on their own — and if their child gets sick, they are prepared to deal with it," she said.

Randy Heikens, a father of three from Spencer, told senators that parents deserve a choice of whether to vaccinate their children. "I feel the children belong to the parents, not to the state. If you don't believe that, go to North Korea," he said.

Kate Linkenmeyer, a pediatrician training in Des Moines, told senators about treating children who hadn't been vaccinated.

"I watched a 15-year-old child slowly die in front of me because of influenza," she said. "We've all seen it, and it's heartbreaking, and you don't come back from watching someone die from these preventable diseases."

Although the flu shot isn't among the vaccinations required of Iowa children, it is recommended by public health leaders.

Willie Rosin of Britt, a pastor who has two children with compromised immune systems, said he supports broad vaccination so his kids aren't exposed to others carrying preventable diseases. "I'm thankful for the medical community that continues to push for high vaccination rates," he said.

Sen. Jim Carlin, R-Sioux City, voted to pass the bill out of subcommittee. He said he believes in the value of vaccinations, but understands why some people question the dozens of shots now required for children. "This merits further conversation," he said.

But Sens. Herman Quirmbach, D-Ames, and Tom Greene, R-Burlington, voted against the bill.

Greene, who is a retired pharmacist, said he generally agrees with parents' right to control what happens to their children. But "vaccines overall, are the most significant, positive public health issue that we have benefited from over the last 150 years," he said. Greene said he was voting against expanding vaccination exemptions because of the public-health implications.

A separate subcommittee, made up of Greene, Sen. Joe Bolkcom, D-Iowa City, and Carlin voted 2-1 against a bill that would have barred clinics from dismissing patients who refused vaccination.

Supporters of the proposals are now pinning their hopes on the Iowa House, where similar bills are expected.

Iowa's current vaccination exemptions

The number of Iowa parents obtaining religious exemptions to vaccination requirements is jumping amid continued fears that the shots can be harmful.

No major religion teaches that vaccinations are wrong, but parents don't have to specify any tenet when applying for a religious exemption to them. The number of such exemptions in Iowa has more than tripled, from 2,572 in the 2006-07 school year to 8,740 in the 2017-18 school year, according to the Iowa Department of Public Health. Meanwhile, the number of medical exemptions has nudged up from 1,461 to 1,852.

Gov. Kim Reynolds told reporters Tuesday that she hadn't read the vaccination exemption bill, but she supports vaccinations and Iowa's current law on exemptions. "We already actually have an opt-out process already in place," she said. "I think we’ve already addressed some of the concerns in the existing opt out that we have."