After an all-night hearing with hundreds signed up to testify, a Colorado House committee gave its approval early Tuesday to a bill that creates a way to track and discourage exemptions to school vaccinations.
The 7-4 party-line vote came after hours of passionate testimony and health theories on both sides of the argument.
The bill does not require vaccinations. Instead, it creates a standardized form for parents to fill out to help keep track of vaccination rates and exemptions.
Parents or guardians could still choose not to have their child vaccinated for health reasons, religious beliefs or other personal convictions. But now exemptions are handled by local schools, without the state's involvement.
According to the Centers for Disease Control and Prevention, the vaccination rates for Colorado kindergarteners ranks 49th out of 49 states that report data.
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The state health department reported last year that immunization rates were 93 to 95% for five of six vaccinations required for school-aged students, a slight increase over the last two years. But the rates varied widely by school, with a small number having immunization rates of 50 percent or less, Chalkbeat Colorado reports.
The goal is to increase vaccinations, but opposition to House Bill 1312 see it as government overreach; some don't think vaccines are safe for their children. Vaccine makers, they noted, are shielded from liability.
Rep. Susan Beckman, R-Littleton, said she had received a volume of emails "like I've never seen before as a legislator."
Based on that, she questioned a statistic the committee heard: That severe allergic reactions from vaccines occur only in about 1 out every million cases.
Dr. Sean O'Leary, a pediatric infectious disease specialist at Children's Hospital Colorado, said science doesn't support most parents' concerns.
"In the vast majority of cases, in my experience, when parents claim vaccines cause this, vaccines cause that, the science does not support those claims," he told the committee. "These emails you're hearing are not supported by science. They're supported by parents believe this is what happened, but just because you believe something doesn't make it fact."
Witnesses told the committee that they or loved ones had suffered complications from vaccines. Others said it was not the role of government to coerce people into a medical decision involved their children.
Theresa Wrangham, executive director of the National Vaccine Information Center, said "there's a litany of things we don't know" about the safety of vaccines.
She said the reporting changes single out parents who choose not to immunize their children for religious reasons.
"I think this is a classic case of discrimination, a back-of-the-bus to get an award," Wrangham said. "... You're holding exempting parents out differently, and that's the basis of discrimination."
Others simply didn't like the government having a say in a family medical decision.
"This is neither your place as legislator or your right," parent Dawn Scott told the committee.
The hours of discussion detoured briefly into a larger immigration debate, as a reason why Colorado might be ranked among the worst states in the nation for vaccinations.
"Could that be because we have a people that don't get shots because they're not here legally, so that is making it rise?" Beckman asked Dr. James Todd, a retired professor of pediatrics who worked at Children's Hospital Colorado.
No, he replied, citing work with public health nurses and immigration populations.
"It turns out the population coming to the United States are better immunized than our children in Colorado," he said. "If you talk to these families, they know what measles does."
Rep. Kyle Mullica, D-Northglenn, pushed back on the idea that the bill goes too far, given the stakes.
He said Colorado schools are at risk of an outbreak of a contagious illness.
"This bill is about one thing, which is safety, nothing more, nothing less," he told the committee.
The bill also calls on health care providers and public agencies to tell parents or guardians they can exempt their child from state immunization data collection, if they claim a medical or religious exemption.
Under the bill, the state health department would be required to develop educational materials on immunizations and distribute them to doctors and health care facilities.
The bill, however, doesn't subject health care providers to regulatory sanctions for not complying with the data-reporting system.
Recording exemptions, however, is one of the goals of the bill
House Speaker KC Becker, D-Boulder, told reporters in her office Monday morning that the state tracks who is immunized, but not who has obtained exemptions.
She said it's possible that Colorado's exemption rate isn't as high as is believed.
"We might find the rate of exemptions is lower," she said.
Noting that some people write out exemption requests on a napkin or an envelope, Becker said that "if you make it a little more difficult" to obtain an exemption — for example, by filing out the form required under the bill — "people won't take the easy way out."
The Children's Immunization Coalition is supporting the bill, saying it will strengthen data reporting and increase vaccination rates.
"If we don't act, I fear the exemptions will continue to rise and our vaccination rates will continue to falter, putting our communities at even greater risk until we eventually have an outbreak," Lindsay Diamond, a Longmont mother who was state health department's official "immunization champion" last year, said in a statement provided by the coalition.
CoPo staff writer Marianne Goodland and 9News contributed to this story.