DENVER (AP) — Colorado lawmakers have abandoned a proposal to make it harder for parents to opt their children out of vaccinations as time runs out in their legislative session.

With many bills still waiting for action, the state Senate decided not to take up the bill Thursday, meaning there won't be enough time to pass the measure before the session ends at midnight Friday.

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The bill would have required parents who don't want their children vaccinated for personal or religious reasons to apply for an exemption in person at their local health or the state health department. Gov. Jared Polis had expressed concerns about that provision so his approval wasn't guaranteed.

The push to raise the bar for exemptions came amid the worst outbreak of measles in the United States in 25 years.

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