Probiotics May Be Useful Against Colds, Flu-Like Symptoms in Children

From Medscape Medical News
Laurie Barclay, MD

August 12, 2009 — Probiotics may be useful as prophylaxis against cold and influenza-like symptoms in children, according to the results of a double-blind, placebo-controlled study reported in the August issue of Pediatrics.

"Selected strains of probiotics have been tested for human health benefits in a variety of disease conditions, but much less is known regarding prophylactic benefits in healthy populations," write Gregory J. Leyer, PhD, from Danisco in Madison, Wisconsin, and colleagues. "This study adds information supporting the use of the probiotics tested for prophylaxis against cold and influenza-like symptoms and compares the efficacy of 1-strain and 2-strain preparations."

The effects of probiotic intake on incidence and duration of cold and influenza-like symptoms during the winter season were evaluated in healthy children aged 3 to 5 years. Of 326 eligible children, 104 were randomly assigned to receive placebo, 110 to Lactobacillus acidophilus NCFM, and 112 to L acidophilus NCFM in combination with Bifidobacterium animalis subsp lactis Bi-07. Children were treated twice daily for 6 months.

Compared with the placebo group, the groups receiving single and combination probiotics fared significantly better in several outcomes. Fever incidence was 53.0% lower with single probiotics (P = .0085) and 72.7% lower with combination probiotics (P = .0009); coughing incidence 41.4% (P = .027) and 62.1% (P = .005) lower; and rhinorrhea incidence 28.2% (P = .68) and 58.8% (P =.03) lower, respectively.

Fever, coughing, and rhinorrhea duration were 32% lower with single strain vs placebo (P = .0023) and 48% lower with the strain combination (P < .001). Antibiotic use incidence was 68.4% lower for single strain vs placebo (P = .0002) and 84.2% lower for the strain combination (P < .0001). Days absent from group child care were also 31.8% lower for single strain vs placebo (P =.002) and 27.7% lower for the strain combination (P < .001).

"Daily dietary probiotic supplementation for 6 months was a safe effective way to reduce fever, rhinorrhea, and cough incidence and duration and antibiotic prescription incidence, as well as the number of missed school days attributable to illness, for children 3 to 5 years of age," the study authors write. "No notable adverse events were attributed to study probiotic strains."

Limitations of this study include failure to evaluate mucosal colonization, underlying mechanisms, or the effect of probiotics in an acute response to signs of illness.

"Daily probiotic dietary supplementation during the winter months was a safe effective way to reduce episodes of fever, rhinorrhea, and cough, the cumulative duration of those symptoms, the incidence of antibiotic prescriptions, and the number of missed school days attributable to illness," the study authors conclude. "L acidophilus NCFM alone was effective. There was, however, a trend for a broader protective effect with the combination of L acidophilus NCFM and B lactis Bi-07."

Danisco USA sponsored this study, employs 2 of the study authors, and has contracted 3 other authors regarding this study.

Pediatrics. 2009;124:e172-e179. Abstract