Affiliations: Laboratory of Microbiology and Probiotics, Institute
of Nutrition and Food Technology (INTA), University of Chile, Santiago,
Chile | Department of Clinical Medicine, Nutrition Training
Program, Faculty of Medicine, Universidad Catolica del Norte, Coquimbo,
Chile
Note: [] Correspondence: Martin Gotteland, Ph.D, Laboratory of
Microbiology and Probiotics, INTA, University of Chile, El Libano 5524, Macul,
Santiago, Chile. Tel.: +56 2 9781471; Fax: +56 2 2214030; E-mail:
mgottela@inta.cl
Abstract: Acute respiratory infections (ARI) are one of the main health
problems in children, particularly in those under 5 years of age. The aim of
this study was to evaluate whether the regular intake of the probiotic
Lactobacillus rhamnosus HN001 affects the frequency, severity or duration of
ARI in children attending day care centers during the winter season. A
double-blind, placebo-controlled trial was carried out in 398 children (1 to 5
years old) who were randomized into two groups to receive daily for 3 months
either 100 mL of a product containing HN001 (10^{10}
bacteria/day) or a control without the probiotic. ARI episodes and symptoms,
absenteeism and antibiotic administration were registered. In a sub-group of
children, oropharyngeal and fecal samples were obtained to detect pathogens,
total Lactobacillus counts and secretory IgA, respectively. When comparing
groups, neither the number nor the duration of the ARI, nor the days of
absenteeism or antibiotic administration were statistically different. No
differences between the groups in the detection rates of Staphylococcus aureus,
Streptococcus pneumoniae and Streptococcus pyogenes in the oropharyngeal
samples were observed along the study. Fecal Lactobacillus counts as well as
sIgA levels increased significantly during the study in the HN001 group,
compared to the control (P=0.027 and P=0.048, respectively). In the conditions
in which this study was carried out, the regular intake of L. rhamnosus HN001
modulated the intestinal immune responses without affecting the frequency or
severity of ARI in children.
