Kaiser Data: Infants With Genetic Diseases Receive On-Time Vaccinations

In 2007, the Vaccine Injury Compensation Program ruled that the family of Hannah Poling, a girl who developed an autistic condition after receiving a concentrated series of vaccinations, was entitled to compensation. The prevailing explanation for Poling's brain dysfunction: Vaccine-induced immune responses exacerbated an underlying mitochondrial disorder.*

The issue of whether children with inborn errors of metabolism (IEM), like mitochondrial disorders, are more susceptible to vaccine-related adverse events was explored by combing data from the vast Northern California Kaiser Permanente electronic medical-record system. Results of the investigation were presented Friday by Kaiser physician Nicola Klein at the annual meeting of the Infectious Diseases Society of America ("Evaluating immunization rates and safety among children with inborn errors of metabolism." Abstract 187).

Klein and her colleagues found no difference in the up-to-date vaccination rates of 79 infants who had IEM and those of 1580 matched, healthy infants.** In addition, vaccination was not delayed during the first year among infants with IEM.

By using data from 322 children with IEM who received any vaccine, Klein et al also found no difference between the rates of ER visits and hospitalizations during the 30 days after vaccination and the same rates on postvax days 31-60. The rationale for the comparison was clarified by Klein at MedPage Today: "If the vaccine was causing any problems, we would expect to see them emerge right around the time of vaccination, not a month later."

MedPage Today also indicated that "children with [IEM] were not more likely than normal children to visit emergency rooms or need hospital care after vaccination"; however, this important finding (if correctly reported) was not included in the meeting abstract, nor was it elaborated by the medical news source.

* Although Poling's mother has implied that the vaccines caused the girl's mitochondrial disorder, a belief that contradicts a general understanding of inborn errors of metabolism and her neurologist father's explanation.

** Up-to-date vaccination rates were assessed at 2 years of age. Subjects were members of the Kaiser system from birth to the age of 3 years during the time period from 1990 to 2007.

HT: MedPage Today.

Update: In an e-mail, Dr. Klein confirms that her study compared ER visits and hospitalizations for the 2 time periods (within 30 days postvax and from 31 to 60 days postvax) only among children with IEM. She further advises that a comparison of ER visits and hospitalizations between healthy children and children with IEM is not appropriate, because the 2 populations are too dissimilar. Children with IEM would be expected to have "higher background rates of ER visits and hospitalizations" than healthy children.