The California Department of Public Health is reporting 760 new cases of whooping cough for the two week period ending August 4th.
More than than two-thirds of the new infections occurred in kids ages 7 to 16. But, health officials say, they're most concerned about infants who are too young to be vaccinated against the highly-contagious respiratory disease that's also known as "pertussis."
More than 60 percent of those hospitalized with whooping cough in 2014 have been infants younger than 4 months of age.
Officials are urging women in their third trimester of pregnancy to get vaccinated, which then allows them to pass their immunity on to their newborns.
Parents are reminded to make sure their kids who are heading back to class get vaccinated, as whooping cough outbreaks have been reported at schools throughout California.
Statewide, 6,930 cases of whooping cough have been reported so far this year.