Patents are designed to protect creations and designs, but how long a patent lasts for is dependent on a number of factors. The length of time that a patent offers protection, depends largely on what type of patent is issued and whether required maintenance fees are paid to keep the patent active. slide 1 of 6.
A viral infection is a disease that can be caused by different kinds of viruses, of which the influenza-virus is best known.
As you might think, bacterial infections are caused by bacteria while viral infections are caused by viruses. Infections caused by bacteria include strep throat, tuberculosis and urinary tract infections. Diseases that result from viruses include influenza, measles, chickenpox, AIDS and the common cold.