California physician groups praised the Assembly's passage of one of the toughest mandatory vaccination laws in the nation, and urged Gov. Jerry Brown to sign it if the bill reaches his desk.
"To make a decision not to vaccinate is actually to make a decision to potentially harm the community," said Dr. Jay W. Lee, president of the California Academy of Family Physicians. "The health of the public is going to be protected by this measure."
Many organized medical groups backed the measure. It would require more children who enter day care and school to be vaccinated against diseases like measles and whooping cough, and end exemptions for parents who cite religious or other personal beliefs against vaccinations.
Physicians said immunization levels have fallen too low to keep Californians safe from disease.
A mother who lost her son nine years after measles infected his brain as a baby said more vaccinations will save lives.
"We went through hell and back, and nobody, no child, no family member, should have to deal with that," said Marissa Cortes-Torres of northern San Diego County. "If we stop the disease … nobody would have to endure that situation."
The proposed law was introduced after the Disneyland measles outbreak that began over the winter holidays, the worst in California since the 1988-91 measles outbreak. More than 150 people were infected. In California, about 1 in 5 patients have been hospitalized.
Doctors defended ending the use of of religious and personal vaccine exemptions for children in school and day care.
"All it takes is one child, who was, through whatever hoop, was able to obtain an exemption, to go somewhere, contract an illness and bring it back to infect the populations that are at greatest risk," said Dr. Hayden Schwenk, clinical assistant professor at Stanford University School of Medicine. "It's hard to approach it halfway."
For instance, a 2008 outbreak of measles in San Diego was started when an unvaccinated 7-year-old boy who visited Switzerland brought back measles, infecting five children at his school, four at his doctor's office and two siblings.
The passage of the bill Thursday, on a bipartisan 46-31 vote, was condemned by opponents, who said they would challenge the law in court and possibly with a referendum if it is signed into law. After the Assembly's vote Thursday, the bill returns to the Senate for minor amendments before it is sent to the governor's desk.
California would be the first state in modern times to pass a law ending non-medical vaccine exemptions for school children. The only two other states with such laws, West Virginia and Mississippi, had those rules passed in a much different environment, said Saad Omer, an associate professor at Emory University and expert in vaccine policy.
Omer said he was concerned anti-vaccine activists could be so incensed if the law passes that it will be subject to challenges after public concern about the Disneyland measles outbreak fades. Other states have taken the less controversial route of making it harder to get vaccine exemptions, he said.
A Public Policy Institute of California survey released in May said 67% of Californians say children should not be able to attend public schools unless they are vaccinated.
"But public attention is somewhat fickle," Omer said. "The general public will stop paying attention to it in six months, a year or two years or three. But people who don't particularly like vaccines, they have had sustained activity despite various outbreaks."