The common cold is one of the most frequent minor illnesses in the world. A large US-American survey showed that over 70% of the population annually was suffering from at least one viral respiratory tract infection. Also the economic burden in the USA was almost USD 40 billion annually causing considerable direct and indirect healthcare costs. Caused by 200 identified types of viruses, the common cold is primarily associated with rhinoviruses. Common cold symptoms may include sore throat, runny nose, general malaise, and low-grade fever at onset, followed by nasal congestion and cough. While benign, they last for several days and cause 40% of all missed work days. Complications also include sinusitis, otitis media and pneumonia, exacerbations of asthma and chronic obstructive pulmonary disease, and serious illness in immunocompromised patients.

Colds typically afflict most adults and adolescents 2-4 times a year and symptoms usually peak around day 3 or 4 and last 1-2 weeks with a median of 7 days. There is no approved specific therapy for URTI, treatment is therefore mainly symptomatic. The most common pharmacological treatments are antipyretics, anti-inflammatory drugs, expectorants, decongestants, and cough suppressants, either alone or in combination. Supportive measures can include bed rest, hot baths, and inhalations, gargling, and drinking plenty of fluids. Antibiotics are widely prescribed, but often is inappropriate because URTI are mostly caused by viruses and are only indicated in the case of bacterial infection. Its overuse can also lead to the development of community acquired resistant pathogens which are an increasing and serious health burden.