An earlier blog discussed a recent report in the New England Journal of Medicine on increasing rates of vaccine refusal by parents and the associated rise in measles cases (see “Why Childhood Vaccines Still Matter,” dated May 20, 2009). Just this past week a new study has come out that reports an association between vaccine refusal and pertussis, another vaccine preventable disease.
Published in the journal Pediatrics, the report concludes that children whose parents refuse to vaccinate them against pertussis are at a 23-fold higher risk of pertussis than children who are vaccinated. Using data from a large HMO in Colorado, the authors identified over 150 children with pertussis and compared them to 600 uninfected children. Whereas children whose parents refused vaccination made up 12 percent of pertussis cases, they comprised only 0.5 percent of the noninfected cases. This finding is further evidence against the commonly held belief that children are no longer at risk for vaccine-preventable diseases.
Pertussis, also known as whopping cough, is a serious infection that spreads from person to person via respiratory contact. The infection causes coughing spells so severe that it can become difficult to breathe. Children are particularly vulnerable to severe infection and sometimes suffer from cracked ribs and pneumonia and require hospitalization. There is no cure for pertussis and so treatment relies on providing supportive care while the infection resolves on its own. Far from uncommon, pertussis is on the rise and affects thousands of children and adults in the United States annually.
In children the vaccine is administered as part of the diphtheria, tetanus, and acellular pertussis series (abbreviated as DTap), which is administered in 5 shots. The first three doses are given at 2, 4 and 6 months of age; the fourth dose from 12 to 18 months of age; and the fifth dose from 4 to 6 years of age. Because immunity against pertussis declines with age, adults are advised to receive a booster shot. The Centers for Disease Control and Prevention (CDC) recommends that adults ages 65 and younger receive the Tdap vaccine (the adult version of DTap) at least once as a substitute for the Td (tetanus diphtheria) vaccine that they should be receiving every 10 years.
- Shantanu Nundy, M.D.
To access the report, visit http://pediatrics.aappublications.org/. The reference is: JM Glanz et al. Parental Refusal of Pertussis Vaccination Is Associated With an Increased Risk of Pertussis Infection in Children. Pediatrics 2009;123;1446-1451.
To access the 2009 Child & Adolescent Immunization Schedule, visit http://www.cdc.gov/vaccines/recs/schedules/child-schedule.htm.
To access the 2009 Adult Immunization Schedule, visit http://www.cdc.gov/vaccines/recs/schedules/adult-schedule.htm.
I'm an internal medicine doctor passionate about keeping people healthy and out of the hospital. For a brief bio 
You must be post call…
“Whereas 12 percent of pertussis cases occurred in children whose parents refused vaccination, only 0.5 percent of the noninfected cases occurred in unvaccinated children.”
I am guessing you meant that 12% of children whose parents refused vaccination were infected, whereas only 0.5 percent of vaccinated children got pertussis?
also
“Because immunity against pertussis declines with age, adults are also advised to receive the diphtheria vaccine”
good piece though – and timely, especially as Oprah is under fire for giving a platform to pseudoscience peddlers – like Jenny McCarthy with vaccines/autism.
Thanks for your comments and for keeping me honest. Regarding the first comment, the study was a case-matched control study not a prospective study. So we can’t say what percent of vaccine refusers were infected. The dominator is infected cases not vaccine refusers. However, you are right that I wrote it incorrectly! Regarding the second, I’m on it.
p.s. I’m actually not post-call but rather stuck revising my manuscript right now. However, the effect on my brain is the same.