By Victoria Colliver
The San Francisco Chronicle
MARIN COUNTY, Calif. — In what could be the worst year for whooping cough in more than five decades, state public health officials broadened recommendations Monday for those who should be immunized against the disease to include seniors and women in their childbearing years.
As of Friday, there were 1,496 confirmed cases in California of whooping cough, the familiar name for pertussis — a fivefold increase over last year. The state has declared the outbreak an epidemic.
“Considering that immunity from pertussis vaccine or disease wears off and that most adults are susceptible to pertussis, now is the time for Californians to get immunized to protect themselves and their families,” said Dr. Gilberto Chávez, the state’s epidemiologist. “In particular, all family members and caregivers of infants should get the booster vaccine.”
Whooping cough, which gets its name from the sound children typically make when gasping for breath between coughs, was once thought to be a disease of the past, but it has made a resurgence. The disease can be deadly in babies, but not so for older children and adults.
The childhood pertussis vaccination does not provide lifelong immunity, and health officials said the disease is cyclical, with an increase in cases every five years. The last significant outbreak was in 2005, the same year a booster shot for the disease became available to offer added immunity for about seven years.
Marin County hit hard
Marin County has the highest rate of diagnosed whooping cough cases in the state, according to the California Department of Public Health. Health officials attributed the county’s numbers at least in part to the large number of parents who choose not to vaccinate their children before they enter kindergarten.
In Marin County, more than 7 percent of kindergartners enter school without their shots, ranking it seventh highest of the state’s 58 counties for the rate of parents who cite “personal belief” in opting out of childhood vaccinations, according to the state public health department. Bay Area counties, on average, opt out at rates of less than 2 percent, while in Nevada County, nearly 19 percent of children enter school without their vaccination due to parents’ beliefs.
Dr. Fred Schwartz, Marin County’s public health officer, said the personal-belief exemption is a contributing factor to the county’s high pertussis rates, but it does not tell the whole story. Schwartz said the outbreak appeared to have hit the county earlier than many other counties - peaking in late May and early June.
“We’ve continued to see a drop-off since that time, but that doesn’t mean our outbreak is over or that there won’t be continuing cases during the summer,” he said. Public health officials said the disease typically hits its peak from July through September.
In addition, in Marin County, the majority of cases in the age groups hit hardest by the disease — children 5 to 17 years old — had up-to-date vaccinations, he said.
Booster shots
As part of the state’s expanded recommendations, health officials stressed that women of childbearing years and anyone who has contact with infants and pregnant women should get the vaccine booster, known as Tdap. The shot combines the pertussis vaccine with a tetanus booster.
The new guidelines recommend the booster shot for anyone 7 or older who was never vaccinated or whose immunization has begun to wear off. For the first time, those older than 64 are being urged to get the booster. Grandparents increasingly are caring for children, and state statistics show that about 75 percent of children who get whooping cough contract it from someone in their household.
Five infants in Southern California have died of the disease, and health officials said a sixth infant death in recent days is under investigation. The infants were all under 3 months old and had not yet been vaccinated.
Many counties, including those in the Bay Area, offer free or discounted booster shots for older children and adults to help reduce the epidemic. People who suspect they have whooping cough should talk to their doctor about being treated with antibiotics.
Copyright 2010 San Francisco Chronicle