Cysts can arise through a variety of processes in the body, including.  1 wear and tear or simple obstructions to the flow of fluid, 2  infections, 3  tumors, 4  chronic inflammatory conditions, 5  genetic (inherited) conditions,  defects in developing organs in the embryo.
1 Acute * sinusitis often develops after a person has had a cold, with symptoms lasting less than 3 weeks. 2  Chronic * sinusitis can last 3 to 8 weeks or longer; it often occurs in people who have allergies or asthma. 3  Recurrent sinusitis consists of several acute episodes of sinusitis in 1 year.
Colds are contagious from about a week before you get them until all of your symptoms are gone, which is sometimes as long as two weeks. You might develop a secondary infection like an earache that lasts longer than contagious symptoms.olds are contagious from about a week before you get them until all of your symptoms are gone, which is sometimes as long as two weeks. You might develop a secondary infection like an earache that lasts longer than contagious symptoms.