WASHINGTON — A federal advisory panel on Wednesday acknowledged in frustration that the medical community lacks remedies to help the nearly 4 million Americans chronically infected with Hepatitis C, a stubborn and wily virus that has eluded both an effective treatment and vaccine.
Although the incidence of new Hepatitis C infections appears on the decline since its peak in 1989, there are an estimated 30,000 new cases annually in the United States and 8,000 deaths. Because of the number of currently infected individuals, experts expect that the incidence of disease and death "could increase by threefold over the next 10 to 20 years, providing there is still no effective intervention," according to Dr. D. W. Powell, head of the internal medicine department at the University of Texas.
The virus, most often transmitted through the blood or contaminated needles, is not easily cleared by the body's immune system. About 85% of those who become infected remain chronic carriers for life and the virus is the leading reason for liver transplantation in the United States.
The virus afflicts the liver and can cause life-threatening liver damage--and more rarely liver cancer--after many years of infection. Roughly 20% of chronically infected patients develop cirrhosis after two decades of infection.
For the Record
Los Angeles Times Friday March 28, 1997 Home Edition Part A Page 3 Metro Desk 1 inches; 28 words Type of Material: Correction
Hepatitis C drug--A story in The Times on Thursday reported that only one drug is available to treat Hepatitis C. There are several forms of the drug interferon that are used for those with the virus.
"Much more needs to be done," said Powell, who chaired a panel of outside experts convened to advise the National Institutes of Health on the virus. "There needs to be considerably more research."
Panel members called for a new research push--similar to that which has occurred with AIDS--to develop more potent antiviral therapies.
Like the human immunodeficiency virus that causes AIDS, the Hepatitis C virus mutates over time, making it extremely difficult to develop a vaccine to protect against infection, or drugs to treat it.
Panel members speculated that, like AIDS, the use of powerful drug combinations, including protease inhibitors, eventually could have an impact on Hepatitis C.
"We need drugs that directly affect the virus," Powell said.
Currently, the only available treatment is the drug interferon alpha-2b, which is injected three times a week, typically for six months. Many patients respond to the drug but suffer a relapse once it is stopped.
The panel recommended that the treatment time be doubled to one year to achieve a more sustained response.
The group also urged infected patients to abstain from drinking alcohol, which can exacerbate liver damage when the virus is present.
The virus is one of six known to afflict the liver.
The infection, which is more common in minority populations than in non-Latino whites, is most frequently transmitted through injection drug use and much less commonly through sex. Before 1989--when scientists first cloned the virus, thereby identifying it--transmission frequently occurred through blood transfusions. But now, screening of the blood supply has made such transmissions rare.
Some people discover their infections only after routine blood tests--often done as part of physical exams--show an elevation in liver enzymes, which are chemicals secreted by liver cells as they are destroyed.
Chronic infection is an "insidious process," the panel said, progressing at a slow rate in the majority of patients during the first two decades after infection.