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The common cold is a viral respiratory infection most commonly caused by rhinoviruses, but other viruses also contribute. Symptoms are generally mild and more annoying than truly dangerous.
Over 200 differnt viruses can cause colds. The most common of these are Rhinoviruses, naked icosahedral RNA viruses. There are over 100 serotypes of rhinoviruses, making immunity to colds all but impossible. Other causes include coronaviruses, enteroviruses, adenoviruses, metapneumovirus and coxsackieviruses.
Most commonly include: runny nose, sore throat, and sneezing. Cough and a mild fever may also be present. Symptoms typically last 1 - 2 weeks.
Infection of respiratory epithelial cells damages ciliary epithelium and reduces clearance of mucus. Inflammation of the epithelium contributes to excess mucus production and fluid secretion (runny nose). Antihistamines target this effect.
Adenoviruses infect mucoepithelial cells via Ig superfamily receptor; usually kill cells. Adenoviruses limit IFN, TNF and MHC-I antigen presentation.
By symptomology.
Generally supportive. Medications such as OTC cold remedies that contain cough suppressants, fever relievers and antihistamines/decongestants relieve symptoms only.
Effective vaccines are unlikely to be developed due to the large number of viruses that cause the cold. Immunity to a particular strain of cold virus is short-lived (~18 months).
A 24 year old male wakes up with a sore throat and a stuffy nose. Over the next day or two he develops a slight headache and a mild fever (101). Taking ibuprofen for the headache and a decongestant/antihistamine relieves his symptoms. A cough lasting one week and a runny nose persisting for another week cause him to lose a few days from work. He recovers without further intervention.
