Response to Bacillus Calmette-Guérin vaccine in full-term and preterm infants

Area of Science:

• Pediatric Immunology
• Vaccinology
• Neonatology

Background:

• Bacillus Calmette-Guérin (BCG) vaccination is crucial for preventing tuberculosis.
• Immune responses in preterm infants may differ from those in full-term infants.
• Assessing BCG efficacy in preterm neonates is important for public health.

Purpose of the Study:

• To compare the delayed immune response to BCG immunization in preterm infants (31.4–34.6 weeks) versus full-term infants.
• To evaluate BCG efficacy using scar size and tuberculin skin test (tuberculin skin test with purified protein derivative [PPD]) reactions.
• To determine if preterm infants exhibit a different response to BCG compared to full-term infants.

Main Methods:

• A comparative study involving 100 newborns, divided into preterm (n=50) and full-term (n=50) groups.
• BCG vaccination administered, followed by scar measurements at 4, 8, and 12 weeks.
• Tuberculin skin test (tuberculin skin test with purified protein derivative [PPD]) performed 16 weeks post-BCG.
• Positive reactions defined by scar diameter ≥5 mm and PPD induration ≥5 mm.

Main Results:

• No statistically significant differences were observed in the percentage of positive BCG scars (64% preterm vs. 80% full-term, P=0.142).
• Mean scar diameters were similar (4.5 mm preterm vs. 5 mm full-term).
• Tuberculin skin test (tuberculin skin test with purified protein derivative [PPD]) positivity rates (81% preterm vs. 86% full-term, P=0.74) and mean induration sizes (6.7 mm preterm vs. 6.8 mm full-term) were comparable.

Conclusions:

• Preterm infants (31.4–34.6 weeks) demonstrate a similar delayed immune response to BCG vaccination as full-term infants.
• BCG immunization appears equally effective in inducing cell-mediated immunity in both preterm and full-term neonates.
• No BCG-related complications were reported in either group, suggesting a favorable safety profile.