CDC: Hepatitis C Testing Requires Both Antibody Screening and HCV RNA Follow-up

Half of all people who receive an initial hepatitis C virus (HCV) antibody screening test never return for follow-up viral load testing to determine if they are still infected, according to a recent Centers for Disease Control and Prevention (CDC) study. Confirmatory testing is needed to link people with chronic hepatitis C to appropriate care and treatment. "You may not remember what you did in the 60s and 70s," said CDC director Thomas Frieden,"but your liver does."

Approximately 3 million people in the U.S. have hepatitis C, but experts estimate that 3 out of 4 are unaware they are infected. Even among those who take the first step of testing, 51% do not receive necessary follow-up, according to the latest Vital Signs report in the May 7, 2013, advance edition of Morbidity and Mortality Weekly Report. Frieden and John Ward, director of the CDC's Division of Viral Hepatitis, discussed the importance of the findings in an accompanying media briefing.

An HCV antibody test indicates that a person has been exposed to HCV infection and produced antibodies in response. A follow-up test for HCV genetic material tells whether the virus is still present in the body. About 20% of infected people (or less, if they are coinfected with HIV) can clear HCV on their own without treatment, but the majority develop chronic or long-term infection.

Hepatitis C is most common among "Baby Boomers" in the U.S. -- individuals born between 1945 and 1965. Many young people were infected during the 1960s and 70s, often via occasional drug experimentation, and are only now reaching the stage of serious liver disease.

Over years or decades chronic HCV infection can lead to severe complications including liver cirrhosis (scarring), hepatocellular carcinoma (a type of primary liver cancer), end-stage liver failure, and death. According to Frieden and Ward, about half of people with chronic hepatitis C will develop cirrhosis and one-third will die of liver-related causes. Hepatitis C is the most common reason for liver transplants and the leading cause of liver cancer, which is the fastest-rising cause of cancer death in U.S.

Fortunately, it is possible to stop the progression from HCV infection to severe liver disease. Hepatitis C treatment is now better than ever, with more effective and tolerable interferon-free regimens expected in the next 2-3 years. Being aware of infection can also prompt people to take other steps to protect their liver, including limiting alcohol consumption and getting vaccinated against hepatitis B.

"Not everyone with hepatitis C will need treatment, but everyone should be linked to care to determine whether treatment is needed," Frieden said. "Care and treatment could really save your life." Healthcare providers should implement "automatic systems" for complete testing to ensure that people don't fall through the cracks, he urged.

Accompanying the Vital Signs report, the May 7 MMWR also includes updated hepatitis C testing guidance for clinicians and laboratories. The update reinforces guidelines issued last year, which recommend that everyone born between 1945 and 1965 get tested for HCV at least once, regardless of traditional risk factors, but it underscores the need for follow-up testing to determine current infection.

"Persons with current infection who are not identified as currently infected will not receive appropriate preventive services, clinical evaluation, and medical treatment," the guidance reads in part. "Testing strategies must ensure the identification of those persons with current HCV infection."

"The most important question is, 'Am I still infected?'," said Ward. He noted that the sooner follow-up testing is done, the better, "but there's no time limit beyond which it's no longer helpful."

Below is an edited excerpt from a CDC press release describing the study and the updated testing guidance in more detail. A summary fact sheet and infographic are also available online.

Study Suggests Only Half of Americans with Hepatitis C Receive
Complete Testing for the Virus

CDC reinforces need for appropriate follow-up testing for current infection

Only half of Americans identified as ever having had hepatitis C received follow-up testing showing that they were still infected, according to a Centers for Disease Control and Prevention analysis of data from a multi-area study published today in the CDC report Vital Signs.

"Many people who test positive on an initial hepatitis C test are not receiving the necessary follow-up test to know if their body has cleared the virus or if they are still infected," said CDC Director Tom Frieden, MD, MPH. "Complete testing is critical to ensure that those who are infected receive the care and treatment for hepatitis C that they need in order to prevent liver cancer and other serious and potentially deadly health consequences."

Testing for hepatitis C includes a blood test, called an antibody test, to determine if an individual has ever been infected with the virus.  For people with a positive antibody test result, a follow-up test -- called an RNA test -- should be given to determine whether they are still infected so they can get needed care and treatment. 

A small number of people with antibody-positive tests will have cleared the infection on their own, but most people with hepatitis C (about 80 percent) remain infected and can go on to develop significant health problems.

For the Vital Signs study, researchers looked at data from eight areas across the nation funded by CDC to conduct enhanced surveillance for hepatitis C virus infection. Of the hepatitis C cases reported in these areas (i.e., those cases with antibody-positive results), only 51 percent of the cases also included a follow-up (RNA) test result that identified current infection.  Without follow-up testing, the other half are likely unaware if they are currently infected and therefore cannot get appropriate medical care.

Data included in this analysis also underscore the severe impact of hepatitis C among baby boomers. In the eight areas studied, 67 percent of all reported cases of current infection were among those born from 1945 through 1965. Deaths among people with hepatitis C also were more common among those born during these years (accounting for 72 percent of all reported deaths).

"Hepatitis C has few noticeable symptoms, and left undiagnosed it threatens the health of far too many Americans -- especially baby boomers," said John Ward, MD, director of CDC’s Division of Viral Hepatitis. "Identifying those who are currently infected is important because new effective treatments can cure the infection better than ever before, as well as eliminate the risk of transmission to others."

Overall, approximately 3 million Americans are infected with hepatitis C and up to 3 out of 4 do not know they are infected. The vast majority of those affected are baby boomers, or those born from 1945 through 1965. Left untreated, hepatitis C can cause serious liver damage, including liver cancer. Hepatitis C is a leading cause of liver cancer and the most common indication for liver transplants. In fact, liver cancer is the fastest-rising cause of cancer-related death in the United States. Deaths from hepatitis C have nearly doubled over the past decade, now accounting for more than 15,000 deaths each year. 

In light of increasing evidence that many patients are not receiving the follow-up test, as well as recent changes in testing technologies and the availability of new effective treatments for hepatitis C, CDC is issuing updated guidance for health care providers on hepatitis C testing. These guidelines reinforce the recommended process for hepatitis C testing and underscore the importance of providers conducting follow-up RNA testing for all patients with a positive antibody test result in order to help ensure people infected with hepatitis C are properly tested and identified.

CDC recommends that everyone in the United States born from 1945 through 1965 be tested for hepatitis C. CDC also recommends that other populations at increased risk for hepatitis C get tested, including those who received blood transfusions or organ transplants before widespread screening of the blood supply began in 1992, or those who have ever injected drugs.

This Vital Signs coincides with Hepatitis Awareness Month and National Hepatitis Testing Day on May 19.

5/7/13

References

K Bornschlegel, D Holtzman, M Klevens, J Ward, et al. Vital Signs: Evaluation of Hepatitis C Virus Infection Testing and Reporting -- Eight U.S. Sites, 2005–2011. Morbity and Mortality Weekly Report 62:1-5. May 7, 2013 (Early release).

J Getchell, K Wroblewski, A DeMaria, J Ward, et al. Testing for HCV Infection: An Update of Guidance for Clinicians and Laboratorians. Morbity and Mortality Weekly Report 62:1-4. May 7, 2013 (Early release).

Other Sources

CDC National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention. Study Suggests Only Half of Americans with Hepatitis C Receive Complete Testing for the Virus. Press release. May 7, 2013.

Hepatitis C: Testing baby boomers saves lives. CDC Vital Signs. May 2013.