Whooping cough, a disease for which Americans have had a vaccine available since the 1920s, is on pace to infect a record number of Contra Costa County residents in 2011. Last year was bad enough, with a record 205 cases reported — but this year is looking even worse, Contra Costa Health Services reported yesterday. To date, at least 78 cases have been recorded in Contra Costa out of 1,080 statewide — more than 7 percent of the total. Contra Costa County's population of 1.03 million, by contrast, is only 2.8 percent of California's 36.96 million. That's an infection rate of 7.5 per 10,000 in Contra Costa versus 3 per 10,000 in the state as a whole.
Contra Costa County Immunization Coordinator Erika Jennsen said she had no idea why the county was seeing a higher infection rate than the rest of the state. In 2010, when whooping cough swept across California in numbers not seen in six decades, Contra Costa County’s 205 cases represented only 2.6 percent of the state’s total 7,800 cases. At the county’s current infection rate, it would see 234 cases by the end of the year, a 14 percent increase over 2010, while the state is on pace to see a 42 percent decrease. In 2009, Contra Costa County reported only 20 cases. "This is way beyond the normal three- to five-year cycles,” Jennsen said. “It’s very frightening.”
Also known as pertussis, whooping cough is a highly contagious respiratory illness that can be fatal for infants, particularly those under six months who have not completed immunization. Three infants have already been hospitalized for whooping cough in Contra Costa County this year.
The whooping cough vaccine is widely available though health-care providers across the East Bay. Contra Costa Health Services' Public Health Division also hosts weekly drop-in immunization clinics for people without health insurance. To help control the disease's spread, a new state law requires all students in private and public schools entering seventh through twelfth grade in the fall to prove they've received a whooping cough booster. Pertussis immunity begins to wane ten years after the vaccine is given, and most middle-school students were last immunized before entering kindergarten, between the ages of four and six. Health officials advise all people to be vaccinated, cover their coughs, and stay home if infected.