The common cold, while usually harmless, is an annoying illness that affects most people at some point during the year. Between a runny nose, the sore throat, and a constant feeling of being run-down, colds can feel a lot more serious than they generally are. Whatever the causes of the common cold, most people exhibit symptoms for about a week before the body fends off the invaders causing it. Though children under six are the most likely to contract a cold, it’s common for adults to have at least one cold every year.

1. The Cold Virus

A cold is a viral infection of the upper respiratory tract that causes a sore throat and a runny nose, and several other issues. Many different viruses cause colds, such as a human coronavirus and various influenza viruses, but the most common is rhinovirus. This agent thrives in the distinctive temperature of the human nose. Several different methods of transmission and risk factors increase the chance of a person contracting the common cold.

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