Health officials have declared California's measles outbreak over, but the legislative response is just getting rolling.
The outbreak started at the Disneyland theme park and sickened 131 Californians and another 16 people from other states.
The surging number of cases of a disease that was declared eliminated in the U.S. 15 years ago put new pressure on public health officials and lawmakers to boost vaccination rates and end exemptions often invoked by parents who believe childhood vaccines are connected to rising rates of autism—a belief that was debunked again by new research published this week.
In response to the California outbreak, a former school board president and a pediatrician introduced a bill in the state Senate to limit “personal belief” exemptions to school district vaccination requirements.
The bill moved out of the education committee on a 7-2 vote Wednesday after the co-sponsors, Democrats Dr. Richard Pan and Ben Allen, added amendments to exclude from the stricter vaccination requirements children who are home-schooled or are in a school district-sponsored independent study program. The bill was approved earlier this month by the health committee and now goes before the judiciary committee for review.
Opponents and supporters alike predict more amendments will be added as the bill slogs its way through the legislative process.
“This bill has a long way to go; I'm not completely satisfied,” said Sen. Carol Liu, the committee chairwoman. She acknowledged the public health necessity of the bill, but she also expressed concerns for parental rights before voting to move the bill out of her committee.
Sen. Connie Leyva, a Democrat representing parts of San Bernardino and Los Angeles counties, voted against the measure. She cited her concerns for the rights of parents who couldn't afford to home-school their children.
But Sen. Bill Monning, the state Senate Majority leader, said “The public health of all Californians is our charge,” and that the personal choice to not vaccinate children has “community consequences.”
Sen. Marty Block, a San Diego Democrat, said he was convinced to vote “yes” after Pan showed him a computer modeling program from the University of Pittsburgh that simulates how quickly a measles outbreak could spread depending on a community's vaccination rate.
Only Mississippi and West Virginia do not have laws allowing parents to opt out of school district vaccination requirement for either religious or personal beliefs. As of February, bills aimed at tightening exemptions had been introduced in 12 states, according to the National Conference of State Legislatures.
Florida allows parents to opt out of vaccinating their children on religious grounds and does not have an active vaccine bill before its legislature. But there is concern about measles in the state.
Previously, the state's last case of measles had been identified in 2013, but the Florida Department of Health reported Tuesday that a new case of the measles was confirmed in an unvaccinated adolescent patient in Indian River County who had since recovered. Two cases among unvaccinated adults also had been reported in the county recently, as had one case with an unvaccinated 6-year-old in St. Lucie County.
The source of the virus has not been discovered for these cases, which are considered “locally acquired.” A department spokesman said five other cases had been identified among visitors to the state.
Part of the resistance to childhood vaccinations is a belief that they are linked to an increase in autism. The theory is generally traced to a now-debunked 1998 study published in a British medical journal.
A new National Institute of Health-funded study published this week in JAMA again found no harmful association between the measles-mumps-rubella, or MMR, vaccine and autism spectrum disorders.
Researchers examined claims data from a commercial health plan for 95,727 children continuously enrolled in the plan from birth to five years old between 2001 and 2012 and who had an older sibling enrolled for at least six months between 1997 and 2012.
The findings held true among children who were considered at higher risk for autism because they had older siblings with ASD.
“The only conclusion that can be drawn from the study is that there is no signal to suggest a relationship between MMR and the development of autism in children with or without a sibling who has autism,” wrote Dr. Bryan King, with the Seattle Children's Autism Center in an accompanying editorial.
One link the researchers did find, however, was a lower vaccination rate among younger siblings of autistic children.
Vaccination rates for children who did not have an older sibling with autism were 84% at two years old and 92% at five years. In contrast, the rates for children who had older siblings with autism were 73% and 86%.
“As the prevalence of diagnosed ASD increases, so does the number of children who have siblings diagnosed with ASD, a group of children who are particularly important as they were undervaccinated in our observations as well as in previous reports,” the researchers wrote.