The effect of probiotics, prebiotics and synbiotics in formula milk towards the incidence of acute respiratory infection on 1-5 years old healthy children in day care centres

The incidence and the transmission of acute respiratory infection (ARI) in children, especially those at daycare centres (DCCs), are still high. The aim of this study is to investigate whether probiotics, prebiotics, or synbiotics in formula milk can lower the incidence and duration of ARI in healthy children at DCCs. This randomized, double-blind, and placebo-controlled clinical study was performed in 12 DCCs. Healthy children aged 1-5 years were recruited. The subjects were divided into four groups (probiotic, prebiotic, synbiotic and control); the intervention lasted for 26 weeks. Statistical analysis included analysis of variance, Fisher's exact test, chisquared, Relative Risk Reduction (RRR), Absolute Risk Reduction (ARR) and Number Needed to Treat (NNT). Chi-squared analysis for ARI incidence and duration for the probiotic and synbiotic groups showed significantly different results compared to the control group (p < 0.05). The NNT calculation showed that synbiotics provided the best prevention from ARI (NNT = 6.25). The use of probiotics, and synbiotics decreased the incidence of ARI in healthy children, but the best prevention for ARI was conferred by synbiotics.