SAN DIEGO – California officials are battling the worst whooping cough epidemic to hit the state in seven decades as a recent rebound in cases raises questions about the effectiveness of the pertussis vaccine.
Doctors emphasize that the inoculation has led to fewer deaths than in the past and in instances where people do get sick, their illnesses aren’t as severe. But California officials say the limited protection of the vaccine introduced in the 1990s has led to the rise in cases. Research has shown it doesn’t last as long as the one it replaced, and a new study suggests the vaccine may not prevent the spread of the disease.
Whooping cough peaks every three to five years, and California’s last epidemic was in 2010. But despite an aggressive public health campaign in response, the current outbreak is worse.
A total of 9,935 cases were reported to the California Department of Public Health from Jan. 1 to Nov. 26 – the highest number in 70 years. The cases included one infant who died. Elementary, middle and high school outbreaks have occurred across the state.
The bacterial infection causes uncontrollable, violent coughing, which often makes it hard to breathe. People often take deep breaths which result in a “whooping” sound.
San Diego County is among the hardest hit areas with 1,819 cases reported so far this year.
“We’d have to go way back to the 1940s to find more cases,” said Dr. Eric McDonald, medical director of the epidemiology and immunization branch for public health services in San Diego County.
That’s when whooping cough was common, causing hundreds of thousands of illnesses annually and thousands of deaths. But after a vaccine was introduced in the 1940s, cases dropped to fewer than 5,000 a year.