I went for a blood test a few years ago and the results showed the presence of the hepatitis C antibody. My doctor tells me not to be concerned, since I do not exhibit any signs of the disease. I also do not drink alcohol or engage in sex with any partner other than my wife of 19 years. When I was five years old, I had an accident and was given a blood transfusion. I might have been exposed to hepatitis C at that time. My questions are: Do I run the risk of developing hepatitis C in the future? What can I do to get rid of the antibody so that I can donate blood? What precautions should I take now to prevent the disease?

Concerned

The fact that you tested positive for hepatitis C antibody means that you have been infected with the hepatitis C virus. The virus can cause an acute liver inflammation (hepatitis), identical to that caused by hepatitis B. In about 90 percent of people with hepatitis C, the virus causes a chronic infection of varying severity. In many cases, there are no symptoms for many years, if not forever. In others, the infection is an unrelenting, severe disease that results in cirrhosis (scarring) of the liver and death. No one knows for sure what percentage of people with hepatitis C will develop severe liver disease, because many, many people have the virus and do not know it, and long-term studies have not been done. Probably fewer than 10 percent, and maybe significantly fewer, will get severe disease.

What should you do now? You should periodically have a blood test to check the levels of your liver enzymes (called AST and ALT). Damaged liver cells spill some of their enzyme contents into the bloodstream. If the enzyme levels stay low, then it is likely that you do not have significant ongoing liver damage. If the enzymes are persistently elevated, you may be a candidate for therapy. Interferon (a natural protein that helps the body fight viral infection) and another drug called ribavirin (trade name Virazole) can often fight the liver disease associated with hepatitis C. Unfortunately, the drugs can have side effects, they must be taken for 12 months, and they are not effective for everyone. In addition, a large number of patients relapse after stopping the drugs.

What else can you do to help minimize your risk of the more severe forms of the disease? First, you should not drink alcohol. There seems to be an additive destructive effect of alcohol on the liver in patients with hepatitis C. In fact, almost a third of patients who get cirrhosis with hepatitis C are chronic alcoholics. Also, you should probably be vaccinated against hepatitis A, another virus that infects the liver. A recent study showed that in patients with hepatitis C, hepatitis A is much more likely to be a severe illness.

As to blood donation, you can never donate blood again. The blood bank will test for hepatitis C antibody, and you will always test positive. This is a good rule, anyway, because there is no reason to take chances with the blood supply. If they had tested for hepatitis C when you were a child (the test was unavailable then), you probably would never have developed the infection.