A new study shows that children who are not vaccinated for pertussis because of parental refusal have a higher risk of contracting the disease, but whether this news will help convince parents ambivalent about immunization remains to be seen.
The case-control study (Glanz JM et al. Pediatrics. 2009;123:1446-1451) of 156 laboratory-confirmed pertussis cases between 1996 and 2007 found that while unvaccinated children made up about 0.5% of the examined population, they accounted for about 12% of the pertussis cases. “Many of the parents who refuse have the common perception that their child is not at risk—that they are protected by proxy—and our study showed that they are at risk and highlights the need to immunize,” said Jason M. Glanz, PhD, lead author and an epidemiologist with Kaiser Permanente Colorado's Institute for Health Research.
Mitka M. Unvaccinated Children Face Pertussis Risk. JAMA. 2009;302(3):242-244. doi:10.1001/jama.2009.969