One who has not received a vaccine, or any vaccines.
Health authorities have avoided doing research comparing vaccinated v. unvaccinated populations, but some pilot studies have been done. All show that vaccinated populations have higher rates of autism than unvaccinated populations.
The 2013 IOM Report: “The Childhood Immunization Schedule and Safety: Stakeholder Concerns, Scientific Evidence, and Future Studies” says that it has evaluated doing such studies, that they would be doable, useful, but expensive, time consuming and difficult, so they don’t recommend them. Here is their full statement on vaccinated v. unvaccinated studies:
“The committee’s literature searches and review were intended to identify health outcomes associated with some aspect of the childhood immunization schedule. Allergy and asthma, autoimmunity, autism, other neurodevelopmental disorders (e.g., learning disabilities, tics, behavioral disorders, and intellectual disabilities), seizures, and epilepsy were included as search terms. Furthermore, the committee reviewed papers on immunization and premature infants.
In summary, few studies have comprehensively assessed the association between the entire immunization schedule or variations in the overall schedule and categories of health outcomes, and no study has directly examined health outcomes and stakeholder concerns in precisely the way that the committee was charged to address in its statement of task. No studies have compared the differences in health outcomes that some stakeholders questioned between entirely unimmunized populations of children and fully immunized children. Experts who addressed the committee pointed not to a body of evidence that had been overlooked but rather to the fact that existing research has not been designed to test the entire immunization schedule.”
“Initiation of New Prospective Observational Studies
Observational studies are another form of clinical research that can provide useful insights and information that may be used to answer research questions. The committee reviewed opportunities to study groups that choose not to vaccinate using a prospective cohort study design. However, such a study would not conclusively reveal differences in health outcomes between unimmunized and fully immunized children for two main reasons. First, to be informative, cohort studies require sufficiently large numbers of participants in each study group and the sample populations often suggested for use in a comparison of vaccinated and unvaccinated children (such as some religious groups) are too small to adequately power a comparative analysis, particularly in the case of rare adverse health outcomes. Because meaningful comparisons require thousands of participants in each study group and less than 1 percent of the U.S. population refuses all immunizations, the detection of enough unvaccinated children would be prohibitively time-consuming and difficult.
Such a study would also need to account for the many confounding variables that separate some populations from the average U.S. child, including lifestyle factors and genetic variables. To be useful, a comparison would require children matched by age; sex; geographic location; rural, urban, or suburban setting; socioeconomic group; and race/ethnicity.
The committee acknowledges that large-scale, long-term studies of infants through adulthood would be informative for evaluating health outcomes associated with immunization. A new research initiative, the National Children’s Study, is a multicenter, congressionally funded effort that meets these criteria. Although such studies would be the optimal design for evaluating long-term health outcomes associated with the childhood immunization schedule, they would require considerable time and funding, and the committee did not find adequate epidemiological evidence to recommend investment in this type of research at this time.”
“The committee identified concerns among some parents about the number, frequency, and timing of immunizations in the overall immunization schedule. These concerns were not expressed by clinicians, public health personnel, or policy makers in the committee’s review.”
Excerpt:
“No association was found between preterm birth and NDD in the absence of vaccination, but vaccination was significantly associated with NDD in children born at term (OR 2.7, 95% CI: 1.2, 6.0). However, vaccination coupled with preterm birth was associated with increasing odds of NDD, ranging from 5.4 (95% CI: 2.5, 11.9) compared to vaccinated but non-preterm children, to 14.5 (95% CI: 5.4, 38.7) compared to children who were neither preterm nor vaccinated.”
Excerpts:
“NDD, a derived diagnostic measure, was defined as having one or more of the following three closely-related diagnoses: a learning disability, Attention Deficient Hyperactivity Disorder, and Autism Spectrum Disorder.”
“Vaccinated children were significantly more likely than the unvaccinated to have been diagnosed with the following… ASD (4.7% vs. 1.0%, p = 0.013; OR 4.2, 95% CI: 1.2, 14.5),”
“In conclusion, vaccinated homeschool children were found to have a higher rate of allergies and NDD than unvaccinated homeschool children.”
Excerpt:
“This study found statistically significant evidence to suggest that boys in United States who were vaccinated with the triple series Hepatitis B vaccine, during the time period in which vaccines were manufactured with thimerosal, were more susceptible to developmental disability than were unvaccinated boys.”
