WASHINGTON (CBS/AP) — California Sens. Barbara Boxer and Dianne Feinstein are asking state health officials to reconsider the state’s policy on vaccine exemptions.

In a joint letter, the two Democratic lawmakers say there should be no such thing as a philosophical or personal belief exemption to being vaccinated since everyone uses public spaces.

Childhood vaccine has become an emotionally charged topic and a national issue amid a measles outbreak that has sickened more than 100 people across the U.S. and in Mexico.

California is among 20 states that allow for personal belief exemptions and 48 that allow for religious exemptions.

The two senators say they also understand a small number of children cannot be vaccinated because of an underlying medical condition. They stress that the vaccines are effective and necessary.

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