Neonatal Bacillus Calmette-Guérin Vaccination to Prevent Early-Life Eczema: A Systematic Review and Meta-analysis.

Increasing evidence suggests that early-life bacillus Calmette-Guérin (BCG) vaccine could prevent atopic eczema through its beneficial off-target effects. In this meta-analysis, 3 randomized control trials with similar methods were included and enabled robust estimations with low heterogeneity, involving a total of 5655 children randomized to early-life BCG Denmark (n = 2832) or no BCG (n = 2823). Meta-analyses suggest a beneficial effect of BCG to prevent eczema (risk ratio [RR], 0.89; 95% confidence interval [CI], 0.82-0.98). In subgroup analyses, BCG was more beneficial in boys (RR, 0.84; 95% CI, 0.74-0.95) and in children born to 2 atopic parents (RR, 0.81; 95% CI, 0.68-0.97). The NNT to prevent one case of eczema among children of 1 or 2 atopic parent was 20 (95% CI, 12-50). Bacillus Calmette-Guérin Denmark leads to an 11% reduction in the risk of eczema in early life. A greater effect was observed with increasing predisposition. Given its well-established safety profile, neonatal BCG vaccination should be considered for children of atopic parents.