SACRAMENTO: Governor Jerry Brown must now decide whether to sign into law a bill that would require mandatory vaccinations for nearly all California schoolchildren.

The measure, spawned by an outbreak of measles at Disneyland that ultimately infected more than 150 people, cleared its final legislative hurdle Monday in the state Senate. Brown has not said publicly whether he would sign it.

The measure — one of the toughest vaccination bills in the nation — would require children enrolling in school or day care to be immunised against diseases including measles and whooping cough.

Parents would no longer be able to cite personal or religious beliefs to decline the vaccinations, although children with certain medical problems, such as immune system deficiencies, would be exempt.

Those who decline the vaccinations would have to enrol their children in a home-based private school or public independent study program based off campus.

The bill was one of the most contentious taken up by the Legislature this year, attracting large, vocal crowds of parents during a series of legislative hearings on the measure.

Those in favour of the proposal argued that it was needed to boost statewide immunisation rates.

“The science remains unequivocal that vaccines are safe and vaccines save lives,” said Senator Richard Pan (Democrat-Sacramento), a paediatrician and an author of the bill.

Some Republican senators said the bill was government overreach. Senator Joel Anderson (Republican-Alpine) called it “a direct attack on our liberty and a violation of our parental rights.”

After the vote, opponents rallying at the Capitol turned their attention to Brown, calling for him to veto the measure and vowing to hold a constant vigil until he acts.

“I am asking you to protect his health,” said participant Julianna Pearce, referring to her son, Nathan, who she said suffered a severe reaction to a vaccine at 23 months old. “If there is a risk, there must be a choice.”

At a news conference held by the bill’s authors, Hannah Henry, a supporter, said she saw public health benefits in higher immunisation rates.

“The return of preventable infectious disease to our schools and to our communities is too frightening to bear,” said Henry, a Napa mother who co-founded the advocacy group Vaccinate California.

Brown has until July 13 to act on the measure. Evan Westrup, a spokesman for the governor, said Brown “believes that vaccinations are profoundly important and a major public health benefit and this bill will be closely considered.”

The state Senate, which first approved the measure in May, voted 24 to 14 on Monday in favour of minor amendments to the legislation, SB 277 by Pan and Democrat Benjamin Allen of Santa Monica. It passed the Assembly last week.