The study found that the medicine, interferon A, can eliminate all traces of the virus, but it must be given soon after the earliest symptoms of the virus appear.
The approach may have limited practical effect, because early-stage infection is hard to spot. Most people do not immediately realize they have caught the virus, because the initial symptoms are often mild flu-like ills, such as muscle ache and poor appetite.
However, for those who begin treatment within two or three months of contracting hepatitis C, the treatment appears to be virtually 100 percent effective in getting rid of the virus.
"This study may make people aware of how important it is to diagnose hepatitis C," said Dr. Michael P. Manns, a co-author of the study at Hannover Medical School in Germany.
Treatment now often begins after people have carried the virus for many years. The standard in those cases is a combination of interferon A and the antiviral drug ribavirin, which eliminate the virus about half the time.
In an effort to see if earlier treatment would work better, the researchers asked physicians to be alert for early cases and enroll patients in the study. Doctors at 24 hospitals in Germany identified 44 cases this way.
"If somebody is indeed diagnosed with hepatitis C, this is important," said Dr. Adrian Di Bisceglie, medical director of the American Liver Foundation. "It says if you treat them early enough, you get rid of the infection in everybody, and that's fairly dramatic."
The results are scheduled to be published in the Nov. 15 issue of the New England Journal of Medicine. Because of their importance, the results were released Monday on the journal's Web site.
The study was financed by Essex-Pharma, which makes the interferon.
Hepatitis C is usually spread by contact with infected blood. In the latest study, most of the patients caught it through drug abuse, accidental needle jabs in hospitals or surgery.
They started therapy within an average of 89 days of catching hepatitis C. The patients received daily interferon injections for four weeks, then three times a week for 20 more weeks. Forty-eight weeks after the study began, the virus was undetectable in all but one patient.
About 4 million people in the United States and 170 million worldwide are estimated to be infected with hepatitis C. The infection has become much less common since 1991, when blood banks began screening for the virus. Still, hepatitis C infection is the leading cause of chronic liver disease in the United States and the most frequent reason for liver transplants.
Leslie Johnson, a researcher at the National Institute of Allergy and Infectious Diseases, estimated that about 15,000 Americanwill catch hepatitis C this year. Sixty percent will be injection drug abusers.
By Daniel Q. Haney
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