Neonatal BCG and Hepatitis B Vaccination and Incidence of Atopic Dermatitis in Children by 36 Month of Age: Results of Prospective Study.

BACKGROUND

The steady increase in allergic diseases among children has coincided with increased global vaccination coverage and the expansion of routine childhood immunization programs. This has contributed to the widespread belief that there is a possible link between immunoprophylaxis and allergic diseases. However, a number of scientific studies have demonstrated the protective effect of early neonatal immunization on the development of nonspecific immunological protection against infections. This is believed to be due to a shift in the immune response from the Th2 type, traditionally predominant in newborns, to the Th1 type, which reduces the risk of developing allergic diseases.

METHODS

This prospective cohort study analyzed the medical records of 2279 children born between 2018 and 2022 to evaluate the impact of neonatal BCG-M and hepatitis B (HepB) vaccination on the incidence of atopic dermatitis (AD) by 36 months of age. Factors analyzed included family history of allergy, cesarean section, prematurity, delayed initiation of breastfeeding, maternal antibiotic use during pregnancy, and antibiotic use in the child during the first three years of life.

RESULTS

The cumulative incidence of AD by 36 months of age was 19.9%. Timely neonatal vaccination coverage was 76.2% for BCG-M and 69.2% for HepB; by 12 months of age, these rates increased to 90.2% and 88.5%, respectively. A full-term birth demonstrated a significant protective effect (OR 0.52; 95% CI 0.30-0.93). A positive family history of allergy was the strongest predictor of AD (OR 21.49; 95% CI 14.4-32.9). Cesarean section was also significantly associated with AD (OR 1.30; 95% CI 1.01-1.65). AD incidence was comparable between vaccinated (20.5%) and non-vaccinated (17.5%) children (chi-squared with Yates' correction, p = 0.192), indicating no statistically significant overall impact of immunization on AD risk.

CONCLUSIONS

The development of AD is primarily driven by hereditary predisposition and specific perinatal factors rather than by routine immunization. These findings confirm that neonatal BCG-M and HepB vaccination does not increase the risk of AD, providing a scientific basis to address vaccine hesitancy.