Conclusion : Based on the available data and taking into account the safety profile of RCTs , probiotic consumption appears to be a feasible way to decrease the incidence of RTIs in children
Background : Respiratory tract infections ( RTIs ) represent one of the main health problems in children .
Probiotics are viable bacteria that colonize the intestine and affect the host intestinal microbial balance .
Accumulating evidence suggests that probiotic consumption may decrease the incidence of or modify RTIs .
The authors systematic ally review ed data from r and omized controlled trials ( RCTs ) to investigate the effect of probiotic consumption on  RTIs in children .
Bifidobacterium animalis subsp. lactis BB-12 in reducing the risk of infections in infancy.
The impact of controlled administration of Bifidobacterium animalis subsp . lactis BB-12 ( BB-12 ) on the risk of acute infectious diseases was studied in healthy newborn infants . In this double-blind , placebo-controlled study , 109 newborn 1-month-old infants were assigned r and omly to a probiotic group receiving a BB-12-containing tablet ( n 55 ) or to a control group receiving a control tablet ( n 54 ) . Test tablets were administered to the infants twice a day ( daily dose of BB-12 10 billion colony-forming units ) from the age of 1 - 2 months to 8 months with a novel slow-release pacifier or a spoon . Breastfeeding habits , pacifier use , dietary habits , medications and all signs and symptoms of acute infections were registered . At the age of 8 months , faecal sample s were collected for BB-12 determination ( quantitative PCR method ) . The baseline characteristics of the two groups were similar , as was the duration of exclusive breastfeeding . BB-12 was recovered ( detection limit log 5 ) in the faeces of 62 % of the infants receiving the BB-12 tablet . The daily duration of pacifier sucking was not associated with the occurrence of acute otitis media . No significant differences between the groups were observed in reported gastrointestinal symptoms , otitis media or use of antibiotics . However , the infants receiving BB-12 were reported to have experienced fewer respiratory infections ( 65 v. 94 % ; risk ratio 0·69 ; 95 % CI 0·53 , 0·89 ; P = 0·014 ) than the control infants . Controlled administration of BB-12 in early childhood may reduce respiratory infections
Conclusion : Based on the available data and taking into account the safety profile of RCTs , probiotic consumption appears to be a feasible way to decrease the incidence of RTIs in children
Background : Respiratory tract infections ( RTIs ) represent one of the main health problems in children .
Probiotics are viable bacteria that colonize the intestine and affect the host intestinal microbial balance .
Accumulating evidence suggests that probiotic consumption may decrease the incidence of or modify RTIs .
The authors systematic ally review ed data from r and omized controlled trials ( RCTs ) to investigate the effect of probiotic consumption on  RTIs in children .