A new study reports, “Children who aren’t vaccinated against whooping cough are 23 times more likely to develop the disease than children who get all of their shots on time.” The study, “of 751 children enrolled in Kaiser Permanente of Colorado,” revealed that “one in 20 children who skipped the vaccine developed whooping cough, compared with one in 500 vaccinated children.”
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What this all means, according to Sean O’Leary, an infectious-disease fellow at Children’s Hospital in Denver, who was not involved in the study, told USA Today, is that “refusing to vaccinate your child not only puts your child at risk, but puts susceptible children at risk.” 
Still, some parents are refusing “vaccinations because of fear of mercury-based preservatives,” while “other parents space out vaccinations to avoid ‘overwhelming’ a child’s immune system.”
“Though more than 90% effective, the vaccine doesn’t protect everyone,” says Dr. O’Leary. 
“That’s why vaccinating all children is crucial to creating ‘herd immunity’ for the entire community, including newborns who are too young to be immunized.”
Another study in the Pediatric Infectious Disease Journal in March found that 91 babies under age 1 died of whooping cough from 1999 to 2004. More than half were under 2 months old, the age at which infants get their first in a series of whooping cough shots.
The current study authors, however, said that their study’s “results dispel vaccine-refusing parents’ belief ‘that their children are not at risk for preventable diseases,'” the Chicago Tribune adds. 
The team also maintains that the “results are especially troubling, because whooping cough cases have jumped in recent years, and in rare cases the bacterial infection can be deadly.” 
For example, “in 2007, 10,454 cases were reported nationwide, including 10 children who died, government data show.” 
Pediatric infectious-disease specialist Janet Englund of Seattle Children’s Hospital told USA Today, “Vaccines have eliminated killers such as polio, diphtheria and rubella. But because parents no longer see children dying of these once-common illnesses, some parents assume the diseases aren’t dangerous.”
Some parents have refused vaccinations because of fear of mercury-based preservatives. But vaccines have been mercury-free since 2001, Glanz says.
Other parents space out vaccinations to avoid “overwhelming” a child’s immune system. 
But Glanz says there’s no evidence of such an effect. The Centers for Disease Control and Prevention bases its vaccine schedule recommendations on the results of clinical trials that have demonstrated their safety, he says.
WebMD reported, “Although the number of parents who refuse immunizations is small, researchers say that number has increased over the past decade and may be contributing to a rise in the preventable disease cases in children.”
You can read more about my blogs on vaccine myths by using the search box in the left hand column of my blog and searching for “vaccine myths.”