OBJECTIVES: Probiotics may be useful in preventing acute infectious diarrhea. 
Bifidobacteria are particularly attractive as probiotics agent because they 
constitute the predominant colonic flora of breastfed infants and are thought to 
play a role in the decreased incidence of diarrhea in breastfed infants.
METHODS: This was a multicenter, double-blind, controlled study to evaluate the 
efficacy of a milk formula supplemented with viable Bifidobacterium lactis 
strain Bb 12 (BbF) in the prevention of acute diarrhea in infants younger than 8 
months living in residential nurseries or foster care centers.
RESULTS: Ninety healthy children received either the BbF or a conventional 
formula (CF) daily. The mean duration of the stay in the residential center was 
similar (137 v 148 days). At enrollment, there were no differences between the 
two groups with respect to age (3.7 +/- 2.1 months), gender, anthropometric 
data, history of allergy or gastrointestinal disease, frequency of 
breast-feeding in the neonatal period or timing of introduction of solid food. 
Altogether, 28.3% of the BbF infants had diarrhea during the study compared with 
38.7% of controls (NS). There was a statistically insignificant trend for 
shorter episodes of diarrhea in the BbF group (5.1 +/- 3.3 days v 7 +/- 5.5 
days, NS). The number of days with diarrhea was 1.15 +/- 2.5 in the BbF group 
with a daily probability of diarrhea of 0.84 versus 2.3 +/- 4.5 days and 1.55, 
respectively, in the CF group (P = 0.0002 and 0.0014). Feeding infants with the 
BbF reduced their risk of getting diarrhea by a factor of 1.9 (range, 1.33-2.6). 
Analysis of the cumulative incidence of diarrheal episodes showed a trend that 
the first onset of diarrhea occurred later in the BbF group.
CONCLUSION: These results provide some evidence that viable Bifidobacterium 
lactis strain Bb 12, added to an acidified infant formula, has some protective 
effect against acute diarrhea in healthy children.