SAN FRANCISCO (AP) — Two California lawmakers are pushing for new legislation that would ensure more children are vaccinated against measles.

California Sen. Barbara Boxer is joining forces with state Sen. Richard Pan, D-Sacramento, a pediatrician, in touring a Head Start Center in Emeryville, California on Wednesday morning to address the importance ofvaccinations for kids as young as preschool.

The lawmakers penned legislation that would make vaccinations mandatory, except for children with certain medical conditions. The law would mean personal or philosophical opposition to vaccines would not be an authorized exemption for the parents of school-age children.

The number of U.S. measles cases this year has risen to 141, with most of the new illnesses tied to outbreaks at Disneyland in California and an Illinois day care center.

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