|
|
Over time, chronic hepatitis B virus and hepatitis C virus infections can progress to advanced liver disease, liver failure, and hepatocellular carcinoma. Unlike other forms, more than 80% of hepatitis C infections become chronic and lead to liver disease. When combined with hepatitis B, hepatitis C now accounts for 75% percent of all cases of liver disease around the world. Liver failure caused by hepatitis C is now leading cause of liver transplants in the United States.
Warfarin was developed as a consequence of the study of a strange bleeding disorder that suddenly occurred in cattle on the northern prairies of the United States in the early 1900s.
The first war in which wide-scale use of anesthetics occurred was the Civil War, and 80% of all wounds were in the extremities.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
More than 50% of American adults have oral herpes, which is commonly known as "cold sores" or "fever blisters." The herpes virus can be active on the skin surface without showing any signs or causing any symptoms.