Signs and symptoms
The typical symptoms of a cold include a cough, a runny nose, nasal congestion and a sore throat, sometimes accompanied by muscle ache, fatigue, headache, and loss of appetite.[3] A sore throat is present in about 40% of the cases and a cough in about 50%,[4] while muscle ache occurs in about half.[5] In adults, a fever is generally not present but it is common in infants and young children.[5] The cough is usually mild compared to that accompanying influenza.[5] While a cough and a fever indicate a higher likelihood of influenza in adults, a great deal of similarity exists between these two conditions.[6] A number of the viruses that cause the common cold may also result in asymptomatic infections.[7][8] The color of the sputum or nasal secretion may vary from clear to yellow to green and does not indicate the class of agent causing the infection.[