SACRAMENTO, Dec. 16 (UPI) -- With nearly 10,000 cases of whooping cough or pertussis reported in California in 2014, state health officials said the epidemic has reach proportions not seen since the 1940s.
Upticks in cases of the bacterial disease are cyclical, so a rise was expected in 2014, but perhaps not this much of an increase. In 2010, for instance, pertussis also reached epidemic status in the state, with more than 9,000 cases.
"Pertussis is cyclical, meaning it waxes and wanes in incidents over a period of every three to five years," Kathleen Harriman of the California Department of Public Health, told KCRA-TV.
"So, we were sort of expecting that 2014 was going to be a bad year, and it's even worse than we expected this year," Dr. Dean Blumberg, chief of pediatric infectious diseases at the UC Davis Children's Hospital added.
The last time the state saw whooping cough cases with such numbers was in the 1940s, reports from the department indicate.
Doctors suggest the recent spike could be due to the limited effectiveness of the pertussis vaccine, but also better ability to diagnose the disease.
"Pertussis vaccines offer high levels of protection within the first year of completing vaccinations," Dr. Wilma Wooten, a San Diego county public health officer said in June.
"But then the protection decreases over time," she added.
Even with the decreased effectiveness of the vaccine, it still helped to lessen the severity of the disease.
The Centers for Disease Control and Prevention recommend children get the pertussis vaccine at 2 months, 4 months, 6 months 15 to 18 months, and 4 to 6 years.
Whooping cough usually starts with cold-like symptoms, including a mild cough and fever, the CDC says.
Severe coughing and coughing fits can continue for weeks after that, resulting in a loud whooping sound as the infected gasp for air.
In babies under 1 year of age, there may be a dangerous change in breathing pattern.