Aim of this study is to investigate efficacy and safety of Echinaforce Junior Tablets (250mg) in comparison with Vitamin C tablets in the prevention of acute viral respiratory tract infections.

200 children aged 4-12 years are recruited by pediatricians and general practitioners and are allocated to preventive treatment with either Echinaforce Junior tablets or Vitamin C. Children take 3 x 1 tablet per day over a period of 2 months followed by 1 week treatment break and an intermediate study visit (V2). Thereafter children continue with preventive Treatment for another 2 months, followed by exclusion visit (V3).

Parents are required to contact a study coordinator at the occurrence of acute respiratory Symptoms to initiate symptom recording via internet-based e-diary. On day 1 - 3 of episode parents will sample nasal secretion, which will be analysed for common respiratory agents.

Inclusion Criteria:

• 4-12 years
• written informed consent by parents and optionally by child
• daily Access to computer/email
• german language skills

Exclusion Criteria:

• 13 years or older, younger than 4 years
• participation in a clinical study during past 30 days
• intake of antimicrobial, antiviral, immunosuppressive substances, salicylic medicaments (like Aspirin)
• surgical intervention 3 months Prior to inclusion or planned intervention during the observation period
• known Diabetes mellitus
• known and treated atopy or Asthma
• cystic fibrosis, bronchopulmonary dysplasia, chronic obstructive pulmonary disease (COPD)
• diseases of the immunosystem (like autoimmune disorders, degenerative illnesses (like AIDS or leucosis))
• Metabolic or Resorption disorders
• Liver or kidney diseases
• Serious health Problems (e.g. neurological Problems)
• known allergies against compositae (e.g. camomile or dandelion) or any of the substances of the investigational product