California health officials and healthcare professionals are urging Californians to get vaccinated, as the state is on pace for the worst epidemic of pertussis, more commonly known as whooping cough, in more than 50 years. The disease already has claimed the lives of nine infants in the state.

California health crisis

"Whooping cough is now an epidemic in California. Children should be vaccinated against the disease and parents, family members and caregivers of infants need a booster shot," stated Dr. Mark Horton, director of the California Department of Public Health.

As of Sept. 14, there were 4,017 cases of the illness reported for a state rate of 10.3 cases for every 100,000. Of that number, 3,985 of the reported cases experienced disease onset in 2010, according to the California Department of Public Health.

This marks the most cases reported in 55 years, when 4,949 cases were reported in 1955, and the highest incidence in 48 years, when a rate of 10.9 cases/100,000 was reported in 1962. Previously, the peak was in 2005, when there were 3,182 cases reported, according to the CDPH.

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