The Effect of a Probiotic on Upper Respiratory Tract Infections

Study Overview
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Brief Summary
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This study is a randomized, double-blind, placebo-controlled, two-armed, parallel-group study in healthy children aged 2-6 years. The study will investigate the effect of daily intake of a probiotic on Upper Respiratory Tract Infections (URTI) during a 16-week intervention.

Official Title
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The Effect of Lactobacillus Rhamnosus (LGG®) on the Defence Against Pathogens in the Upper Respiratory Tract in Healthy Children - a Single-center, Randomized, Double-blind, Placebo-controlled Study With 16 Weeks Intervention.

Conditions
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Infections, Upper Respiratory Tract

Intervention / Treatment
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* Dietary Supplement: Probiotic strain
* Dietary Supplement: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Children aged 2-6 years, both inclusive, at the time of informed consent No URTI at the time of inclusion as assessed by a GP Attending day-care with at least 10 children or primary school with at least 10 children in the class for at least 20 hours a week Generally healthy as determined by a GP Guardian consents to participate in the study and to comply with all its procedures Exclusion Criteria: Any known concomitant chronic infections, chronic systemic diseases, autoimmune diseases (e.g. asthma), immunodeficiency, metabolic diseases, chronic respiratory tract diseases including respiratory allergies and cystic fibrosis, congenital cardiac defects. Suspected or challenge-proved food allergy Use of any prescribed immune suppressive medications at enrolment Use of oral or IV antibiotics in the 1 month before randomisation Not willing to exclude pre/pro/synbiotics during the study Intake of Echinacea, high dose vitamins or Zinc four weeks before and during the study period. Language limitations regarding interviews or questionnaires Participation in other clinical studies in the last 2 months Planning extensive travel (for >1 month) during the duration of the study

Ages Eligible for Study
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Minimum Age: 2 Years
Maximum Age: 6 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Probiotic<br> | Dietary Supplement: Probiotic strain<br>* Lactobacillus<br>|
| Placebo Comparator: Placebo<br> | Dietary Supplement: Placebo<br>* Placebo<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of URTI | The incidence of URTI measured as the number of URTI episodes diagnosed by a GP according to the prespecified, well-defined criteria, adjusted for sample size. | 16 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of URTI with pathogens | The incidence of URTI measured as the number of URTI episodes diagnosed by a GP according to the prespecified, well-defined criteria, for which a pathogen is identified in nasal swabs, adjusted for sample size. | 16 weeks | 
| The Number of days with URTI symptoms | The number of days with URTI symptoms for URTIs that were diagnosed by a GP, adjusted for sample size. | 16 weeks | 
| The number of days with temperature ≥ 38 °C | The number of days with temperature ≥ 38 °C during an URTI episode, which was diagnosed by a GP, adjusted for sample size. | 16 weeks | 
| WURSS-K score | The Area under Curve for daily Wisconsin Upper Respiratory Symptom Survey for Kids (WURSS-K) score (range: not sick - very sick) during an URTI episode, which was diagnosed by a GP, adjusted for sample size. | 16 weeks | 
| The number of subjects with one or more episode of URTI | The number of subjects with one or more episode of URTI, which was diagnosed by a GP, adjusted for sample size. | 16 weeks | 
| The number of days of absence from daycare or primary school | The number of days of absence from daycare or primary school during an URTI, which was diagnosed by a GP, adjusted for sample size. | 16 weeks |