The California Department of Public Health did not release additional information on the circumstances surrounding the child's death.
The CDPH and the Centers for Disease Control and Prevention recommend pregnant women receive the whooping cough booster shot between 27 and 36 weeks, even if previously immunized.
"To give babies the best protection, I urge all pregnant women to get vaccinated against whooping cough as early as possible during the third trimester of every pregnancy," said Dr. Karen Smith, CDPH director and state public health officer. "The best way to prevent whooping cough is by getting vaccinated."