“The Christchurch Health and Development Study comprises 1,265 children born in 1977. The 23 children who received no diphtheria/pertussis/tetanus (DPT) and polio immunizations had no recorded asthma episodes or consultations for asthma or other allergic illness before age 10 years; in the immunized children, 23.1% had asthma episodes, 22.5% asthma consultations, and 30.0% consultations for other allergic illness. Similar differences were observed at ages 5 and 16 years.”
Effects of diphtheria-tetanus-pertussis or tetanus vaccination on allergies and allergy-related respiratory symptoms among children and adolescents in the United States.
“The odds of having a history of asthma was twice as great among vaccinated subjects than among unvaccinated subjects. DTP or tetanus vaccination appears to increase the risk of allergies and related respiratory symptoms in children and adolescents.”
Delay in diphtheria, pertussis, tetanus vaccination is associated with a reduced risk of childhood asthma.
“Among 11,531 children who received at least 4 doses of DPT, the risk of asthma was reduced to ½ in children whose first dose of DPT was delayed by more than 2 months. The likelihood of asthma in children with delays in all 3 doses was 0.39 (95% CI, 0.18-0.86).”
“The authors shows a correlation between the diphtheria/pertussis/tetanus (DPT) and polio immunizations and asthma episodes, asthma consultations, and consultations for other allergic illness. These findings do not appear to be due to differential use of health services (although this possibility cannot be excluded) or confounding by ethnicity, socioeconomic status, parental atopy, or parental smoking.”