For parents, childhood vaccines are a source of reassurance -- protecting your child against disease naturally helps you sleep better at night -- but also anxiety about side effects and reactions.
With misinformation about vaccines and health problems, it can be difficult for a parent to sort it all out.
For help, WebMD turned to the CDC's Frank DeStefano, MD, MPH, director of its immunization safety office.
Kathleen Harriman, PhD, MPH, RN, chief of the California Department of Public Health's vaccine preventable disease epidemiology section, says 9,477 confirmed, probable, and suspected cases of pertussis were reported to the state in 2010 -- the most in 65 years. Cases have surged in other states, too.
In eight of the California cases that resulted in deaths, the babies had been seen by their doctor or an emergency room doctor but were not initially diagnosed with whooping cough.
The stories were shockingly familiar to Mariah Bianchi of San Francisco.
In 2005, Bianchi lost her newborn son, Dylan, to pertussis. She had sought repeated medical attention for her own symptoms, fearful she would pass on whatever she had to her son, Cole, then 3, and to Dylan.
Once doctors began to suspect pertussis, little Dylan went downhill quickly. He died within 48 hours after doctors started treatment and hospitalized him. He was just over 2 weeks old. Cole recovered.
For Bianchi, the nine deaths were a turning point that increased her commitment to activism. She had joined the immunization coalition in San Francisco in 2009, but now also volunteers for the state coalition. She often shares her experience as she encourages parents to get and keep their children vaccinated, to get a booster shot themselves, and to make doctors aware of the symptoms of whooping cough.
"It breaks my heart that these nine babies' parents are going to have to live with that grief," says Bianchi, a critical care nurse. "It almost takes things like this to make people more aware.”
The Whooping Cough Epidemic: Why Now?
Pertussis can cause serious illness at any age, with early symptoms such as a runny nose and mild cough lasting up to two weeks, and the coughing fits sometimes persisting for 10 weeks or longer. The infection is typically less severe in teens and adults than in babies.
Once the symptoms of the bacterial respiratory infection set in -- including the strong cough that leaves patients making a ''whooping'' sound as they try to catch their breath -- young infants in particular can deteriorate quickly, developing a high white blood cell count, respiratory distress, and deadly pneumonia.
All the California infants who died were under 3 months old and thus not fully protected against pertussis. The five-dose series of pertussis vaccine to protect against whooping cough typically begins at age 2 months, but sufficient protection isn't achieved until about the third dose, at around 6 months, experts say.