By CBS4 Political Specialist Shaun Boyd

BOULDER, Colo. (CBS4) – An outbreak of whooping cough in Boulder has now spread to five schools. It comes as lawmakers convene a vaccine summit at the state Capitol.

Boulder High School

Boulder High School (credit: CBS)

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The lawmakers will hear from people on both sides of the issue at the summit, which takes place in a couple of weeks. There could be a record number, at least a half dozen, vaccine-related bills this upcoming session. Not all will be about improving vaccination rates. There will also be bills to protect the rights of parents who want to opt out.

(credit: CBS)

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Immunization is one of the most contentious issues at the state Capitol. Hundreds of people showed up last year for a bill that would have made exemptions more difficult. This session, an outbreak of pertussis in Boulder County will likely fan the flames this session.

Boulder High School

Boulder High School (credit: CBS)

The county has 78 cases, up from about 58 cases in a typical year. The school district stepped up enforcement of a law requiring parents turn in their kids’ vaccination records or an exemption form. The district says it was missing records on 5,000 kids at the beginning of the school year and now just 23 are missing. About 4% of children in the district are not vaccinated.

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The pertussis vaccine is not 100% protective and it can wear off over time. Colorado sees pertussis epidemics about every three to five years and the last one was in 2012. At this point, state health officials are not overly concerned. Cases of pertussis statewide are down compared to last year.

Shaun Boyd