Nearly 2,000 new cases have been reported in California . ` ` We 're clearly facing an epidemic , '' a pediatrics professor says . Two cases are estimated to occur for every one that 's reported . Nationwide , the number of cases is down this year , the professor says .
Nearly 2,000 pertussis cases have been reported in Texas . `` We 're clearly having an epidemic , '' a pediatrics professor says . Ten cases are estimated to occur for every one that 's reported . Nationwide , the number of cases is down this year , the CDC says .