California's whooping cough epidemic continues to escalate

California's whooping cough epidemic continues to escalate and it could get even worse as kids head back to school this month.

The California Department of Health says there have been nearly 7,000 cases of pertussis so far this year. That's nearly triple last year's cases.

Marin, Sonoma, Napa and Solano counties have substantially higher number of cases than other counties across the state.

There have been more than 2,000 in the Bay Area this year.