A whooping cough epidemic was declared in California Wednesday, after five infant deaths, 910 documented cases and 600 more potential cases of the early childhood disease surfaced through June 15. The latest surge of whooping cough, officially known as pertussis, is on-target to become the worst in 50 years if the outbreak continues at its current pace, according to Mercury News.
The five infant deaths involved babies under 3 months old, an age when they would at most have received one of three sequential pertussis vaccinations typically given at 2, 4 and 6 months. Two final doses of pertussis vaccination are recommended at 15-18 months and 4-6 years. Since 2004, the pertussis vaccination has been available to adults, and California public health officials are recommending that adults who care for young children get vaccinated to help curtail the current outbreak.
The California Department of Public Health put out an advisory to doctors regarding the pertussis epidemic, advising them to consider pertussis when diagnosing patient illness.
What are Typical Pertussis Symptoms?
Whooping cough symptoms differ according to the age of the patient. Infants with whooping cough initially appear to have cold symptoms, with a runny nose and mild cough. Fever is unusual. Apnea, hypoxia (excess oxygen in the lungs) and seizures are possible symptoms. As pertussis worsens, the infant may suddenly experience respiratory distress and the telltale whooping sound may be heard.
In adolescents and adults, whooping cough is often mistaken for asthma or bronchitis. Some possible symptoms include a choking feeling and sweating.
Whooping Cough Epidemic Caused by Nonvaccination?
Whooping cough is cyclical, peaking every two to five years, according to the California Department of Public Health. California experienced 3,182 cases, including eight deaths in 2005. The highest number of whooping cough cases ever recorded in California was 3,837 in 1958.
Blaise Congeni, M.D., of Akron Children’s Hospital, told MedPage Today that 93 percent vaccination rates are necessary to ensure herd immunity against the disease. Herd immunity refers to a vaccination level sufficient to stem the quick spread of a disease once it appears in a community.
Congeni referred to California as “the epicenter of vaccine refusal.” California allows parents to exempt their children from otherwise required school entry vaccinations based on personal beliefs, resulting in lower vaccination rates than many other states.
Rates vary according to community, with MedPage Today reporting an overall rate of unvaccinated school children at 2 percent, with dramatic variations, including 175 schools with 20 percent of their students not vaccinated and a few schools with rates exceeding 70 percent. So, while statewide vaccination rates are sufficient to confer herd immunity, the rates in individual communities may not be.
Will California’s Whooping Cough Epidemic Spread to Other States?
Other states are already experiencing higher than usual pertussis rates this year, including Ohio and Oregon. The Minneapolis/St. Paul area of Minnesota saw a rise in whooping cough cases in May. Central Texas also experienced a surge in pertussis cases earlier this year.