The changing of the seasons, the passage of summer and droves of children returning to school mark the beginning of the cold and flu season.

How often have you heard the old wive’s tale “don’t go outside with your head wet after a shower” or “put your jacket on because you will catch a chill.” Often dismissed as folklore and hearsay, there is mounting evidence to suggest that there is some truth to this.

The common cold is caused by a virus, a small, obligate parasitic package of DNA or RNA that infects a host to replicate. Over 200 different viruses have been identified that cause the common cold. These include different genera of adenovirus, corona virus, enterovirus picornavirus and rhinovirus. Rhinoviruses are estimated to cause up to 50% of colds in humans.

The virus typically infects the upper respiratory system of the nose, sinuses, eyes, pharynx and throat. The virus is usually transferred through aerosolized water droplets in the air and on common surfaces. The vast majority of cold viruses are believed to enter through the nasal passages first.

Infection occurs with binding of the virus to mucosal and surface cells lining these passageways. The virus binds to protein receptors spanning the human cells. Then the virus is fully enveloped and absorbed in the cell or the virus injects........

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