California governor signs mandatory vaccine bill

California Governor Jerry Brown signed a bill into law on Tuesday to impose mandatory vaccination for school-age children in the U.S. west coast state.

The bill was sent to Brown's desk after the state Senate voted a day ago to allow some minor changes to the proposed law passed by Senate in May and then by state Assembly last Friday to boost immunization rates. "The science is clear that vaccines dramatically protect children against a number of infectious and dangerous diseases," Brown said in a statement, "while it's true that no medical intervention is without risk, the evidence shows that immunization powerfully benefits and protects the community."

As the law will take effect next year, California joins Mississippi and West Virginia to be the only states striking both personal and religious belief exemption for immunizations against diseases like measles, mumps and rubella.

Meanwhile, it does allow parents to opt out on medical ground, citing their child's personal or family history.

In acknowledging heated debates around the bill, Brown said he made up his mind "after carefully reviewing the materials and arguments that have been presented."

Some critics have argued that the law would remove parents' ability to decide which vaccines their children receive.

Reports reaching here from Sacramento, where the state Capitol sits, at least one protester was quoted as threatening lawsuit against the bill.

A measles outbreak starting at Disneyland in Orange County, California, in December last year prompted lawmakers to push the bill through the state legislature, hoping that mandatory vaccination would protect public health by achieving "herd immunity" against the spread of disease.

Measles once was eradicated in the United States.

Nevertheless, the U.S. Centers for Disease Control and Prevention (CDC) statistics indicated that 173 people in 21 states and the District of Columbia developed measles this year and 117 of the cases were linked to Disneyland.