A statewide whooping cough epidemic has not changed how Danielle Lawson of San Anselmo feels about vaccinating her 51/2-month-old daughter.
Lawson has declined almost all of the standard vaccines recommended for infants, including DTaP, which protects against whooping cough.
“I haven’t categorically ruled them out,” she said. “But I just think at this point she’s too young, and her immune system is still developing. Nothing goes into my baby right now, except for breast milk, so I don’t feel comfortable injecting her with strange chemicals.”
Public health officials in Marin County, which is by many measures the wealthiest and healthiest county in the state, said this kind of attitude toward vaccinations might be one reason that the county, with a population of just 250,000, currently accounts for about 15 percent of all reported whooping cough cases in California.
Of 58 counties in the state, Marin is ranked seventh — and No.1 in the Bay Area — in parents’ choosing not to get their children the immunizations required for kindergarten. Some 7 percent of kindergartners in the county had a “personal belief exemption” in 2009.
Unfortunately, public health advocates say, the consequences of rejecting vaccination are not strictly personal. Widespread vaccinations not only make disease outbreaks less likely, but they also help protect vulnerable populations like newborns who are too young to get shots.
“Anything that leaves people unimmunized and unprotected, thereby reducing the overall rate of protection in the community, would be a contributing factor when you have an outbreak,” said Dr. Fred Schwartz, Marin County’s public health officer.
Parents who do have their children vaccinated are troubled by others opting out, fearing outbreaks of disease.
“This is the first one to hit us, but how long until we have a chicken pox outbreak, or mumps or polio?” said Sara Sonnet of San Rafael, a mother of two young girls who are both fully immunized. “We take it for granted.”
Whooping cough, or pertussis, is a highly contagious infection of the respiratory tract, and is among the most common vaccine-preventable diseases in the United States, according to the federal Centers for Disease Control and Prevention. It is caused by the Bordetella pertussis bacterium.
The disease is cyclical, with more cases typically popping up every three to five years. The last major outbreak in California was in 2005. The vaccine is not a cure-all; it does not always prevent the disease, and booster shots are needed to retain immunity.
In California, five infants have died from whooping cough this year. In the first six months of the year, 1,337 cases of the illness were reported to the California Department of Public Health, a fivefold increase from the same period last year. The state is on track for its worst outbreak of the disease in 50 years.
As of July 7, Marin had 209 pertussis cases, most among children. The county lags behind state averages when it comes to vaccinations, including students entering school with up-to-date pertussis immunizations, according to the California Department of Public Health. In 2009, 437 kindergartners in the county, or 13 percent, had not had the required shots for whooping cough.
“It’s not a question of access to vaccines,” said Larry Meredith, director of the Marin County Department of Health and Human Services. “There’s a diversity of belief here.”
Lawson and her husband, Jeffrey Lawson, elected not to give their daughter the DTaP vaccine because it also includes immunizations against tetanus and diphtheria.
“I think it would be horrible if my baby got whooping cough,” said Lawson, a graduate of the Massachusetts Institute of Technology who works in finance. “Honestly, if there was a stand-alone pertussis vaccine, I probably would have given it to my daughter. That’s really the only thing that I think that she’s at risk of contracting in the first two years.”
This spring, Ali Long of Mill Valley and her two sons became ill with whooping cough. Her son Zachary, 2 1/2, had not yet received all his pertussis shots and was the sickest.
“I really thought my child was going to die,” Long said. “He would just turn purple and gasp for air. It was the worst experience I have ever had.”
Zachary’s 6-year-old brother fared better. “I am glad that Quincy, my older son, had been vaccinated, because he got a much milder case,” said Long, who is president of a small foundation in Corte Madera.
Long had chosen not to follow the standard immunization schedule proscribed by the disease-control centers. Instead, she staggered her children’s shots, even electing not to have some vaccines administered.
In her home, Long treated whooping cough with herbs, homeopathic remedies and craniosacral therapy, as well as antibiotics. Recovering, but still occasionally coughing, she remains ambivalent about vaccines. “They’re not a panacea,” she said. “They’re putting very strong chemicals into a child’s body that may or may not work.”
Beginning in the late 1940s when a vaccine became widely available, the number of cases of whooping cough in the United States sharply declined. But since the 1980s there has been a slow increase, said Stacey Martin, a staff epidemiologist at the disease-control agency.
The vaccine is about 80 percent effective, said Linda Metz, a public-health nurse for Marin County, which means that people who are immunized may still get sick, but are likely to suffer lighter cases.
“The vaccine is not perfect, but it’s kind of the only protection that we have, and it’s not a fun disease,” said Dr. Sarabenet Sequeira, a pediatrician and homeopath in Mill Valley, who years ago coughed so hard when she had whooping cough that she cracked a rib.
In Sequeira’s practice, most parents who choose to selectively vaccinate still give the DTaP vaccine to their children.
Even children who are fully vaccinated for whooping cough before kindergarten see their immunity wane over time, and that has also been a factor in the Marin outbreak. The disease-control agency recommends that pre-teen pupils get a booster shot.
Unlike most other states, California does not require that booster shot for schoolchildren. A State Senate committee is considering a bill that would require it before seventh grade.
When Heather Chapman of Larkspur got notices from her children’s schools this spring about the whooping cough outbreak, she got her four children immunized.
Others remain unconvinced. Lawson now avoids taking her daughter to the pediatrician, taking her to see a chiropractor instead.
“My feeling is that the pediatrician’s office is full of sick kids,” she said, “and she’s not sick, so there’s really no point in going and exposing her to sick kids.”
This article also appears in the Bay Area edition of The New York Times.