"Frequently you see there was delayed identification of the deceased, and delayed treatment, so I think early treatment goes a long way," says Chavez.
There have also been hang-ups in delivering the vaccine in California's rural areas, where the shots cost more for doctors to administer. Whooping cough causes involuntary, high pitch wheezing and coughing, and infants are especially susceptible to the infection.
California health officials say almost everyone in the state should receive a vaccination for whooping cough. Since the beginning of this year, six infants died from the infection, and more than 1500 Californians have been sickened.