DEAR DR. DONOHUE: I had hepatitis C and endured treatment for one year. After six months of treatment, I tested negative for the virus. What is the likelihood of the virus returning? Will I always test positive for the antibody? Will I ever be able to donate blood or organs? — W.W.

ANSWER: The combination of interferon and ribavirin has greatly improved the prospects for successful treatment of hepatitis C, one of the world’s most prevalent liver infections. The combination can achieve a “sustained virologic response.” That phrase indicates that virus cannot be detected in the blood at the completion of treatment and again six months later. The majority of patients who achieve a sustained virologic response appear to be cured. “Cure” is used with caution, since enough time in monitoring patients has not elapsed to make such a sweeping declaration. Not finding virus in your blood after six months of treatment is a favorable sign that you will obtain a sustained response.

The actual percentage of treated patients who have a sustained response depends on which hepatitis virus strain infects them. When strain 1 is the infecting virus, the sustained response is about 45 percent. When strain 2 or 3 is the infecting virus, the response approaches 80 percent.

Your antibody question is hard to answer. Antibodies are gamma globulins, large proteins that the immune system produces to eliminate germs. They are good guys. Antibodies also serve as lab markers of prior infection. Treatment does decrease antibodies, because the number of viruses dwindles with treatment. Why did you ask the antibody question? It has little to do with success of treatment.

Most organ-donor organizations and blood banks are reluctant to accept donations from someone who has had hepatitis C. They need 100 percent assurance that blood and organs are completely free of virus.

DEAR DR. DONOHUE: I am a 76-year-old man who has been dating a 69-year-old lady. After one year of dating, she advised me she has hepatitis C. Recently my semen has turned brownish. Would the hepatitis C cause this? — J.S.

ANSWER: What you have is, in all probability, hematospermia — blood in the semen. Hepatitis C does not cause it. It comes from the breaking of tiny blood vessels in the passageways that sperm take to reach the outside world, or from broken blood vessels in the prostate gland. Sometimes it results from a genital tract infection, sometimes from small stones in the prostate gland, but most of the time it’s something that just happens.

It worries every man it happens to. He thinks of cancer, but cancer rarely is the cause.

All you have to do is tell your doctor about it. With a few simple tests and an examination, the doctor can give you assurance that nothing terrible is happening.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475.