2. Key Point
Approximately one-third of individuals diagnosed with hepatitis C virus (HCV) infection are not able to identify the source of their infection1
Notes
Patients diagnosed with recent HCV infection were surveyed for potential risks of HCV exposure1
The most common source of HCV infection (~47%) is prior injection drug use, during which the sharing of needles is responsible for transmission of the virus1
Sexual transmission is responsible for 14% of HCV infections1
Healthcare workers can be infected by occupational exposure (eg, needlestick injury); approximately 3% of HCV infections are reported to occur via this route1
Household exposure (eg, transmission of HCV from one family member to another via shaving razor) is not common, and only 1.5% of HCV infections are attributed to this route1
Because of the adoption of blood donor screening practices for HCV in 1992, only 2% of HCV infections result from blood transfusions1
Many HCV-positive individuals remain unscreened and undiagnosed:
Many individuals (~29%) infected with HCV do not identify any of the above activities as likely sources of infection1
A retrospective study of 17- to 74-year-old MCO enrollees from found that only 29% of people who had an identifiable risk factor were screened for HCV2
MCO=managed care organization.
References
Williams IT, Bell BP, Kehnert W, Alter MJ. Incidence and transmission patterns of acute hepatitis C in the United States. Arch Intern Med. 2011;171(3):
Roblin DW, Smith BD, Weinbarm CM, Sabin ME. HCV screening practices and prevalence in an MCO, Am J Manag Care. 2011;17:

3. Key Point
75% of infected individuals are not aware of their hepatitis C virus (HCV) status1
Notes
Identifying individuals who are at risk for chronic HCV infection and who should be screened can be a challenging process that may lead to underdiagnosis1,2
Patients may be reluctant to discuss HCV risk factors or admit to having one
Clinicians may be unaware of risk factors for HCV or reluctant to ask their patients about them. A clinician’s limited knowledge about HCV may make them uncomfortable answering patient follow-up questions
Stigmatization exists within the healthcare system and community that may impede identification of individuals at risk
Increased recognition of the diversity of individuals at higher risk for HCV infection may improve screening rates and subsequent management of those who are infected2
2010 Institute of Medicine recommendations include increased education and tools for healthcare providers to improve awareness of and adherence to screening guidelines1
References
Institute of Medicine. Hepatitis and Liver Cancer: A National Strategy for Prevention and Control of Hepatitis B and C. Washington, DC: The National Academies Press; 2010.
United States Department of Health and Human Services. Combating the Silent Epidemic of Viral Hepatitis: Action Plan for the Prevention, Care & Treatment of Viral Hepatitis

4. HCV is transmitted by blood-to-blood contact3-5
Key Point
Identifying individuals with a higher prevalence of hepatitis C virus (HCV) infection than the general population is an important first step for screening and diagnosis1,2
Notes
HCV is transmitted by blood-to-blood contact3-5
Initially, the receipt of a blood transfusion or blood products was a major route of infection for HCV. In 1992, a widespread campaign of blood donor screenings for HCV was initiated and helped reduce the number of HCV infections due to transfusions to less than 1 per 100,000 units transfused4
Certain populations, such as HIV-positive individuals, African Americans, and baby boomers have higher rates of chronic HCV infection than the overall population5-7
In the United States, an estimated 82% of people with HCV were born between 1945 and 1965 (baby boomers)6
For African Americans, the rate of chronic HCV infection is 2 times the rate for Caucasians, 3% compared with 1.5%, respectively, and is 14% in African American men who are years old7
Identifying individuals who are at increased risk for chronic HCV infection and who should be screened can be a challenging process that may lead to underdiagnosis1
While there are limited data available on healthcare providers’ knowledge of HCV infection, there is a need for increased screening, diagnosis, and treatment of individuals who have HCV2
HIV=human immunodeficiency virus.
References
United States Department of Health and Human Services. Combating the Silent Epidemic of Viral Hepatitis: Action Plan for the Prevention, Care & Treatment of Viral Hepatitis
Institute of Medicine. Hepatitis and Liver Cancer: A National Strategy for Prevention and Control of Hepatitis B and C. Washington, DC: The National Academies Press; 2010.
Centers for Disease Control and Prevention. Hepatitis C FAQs for the Public Accessed August 9, 2011.
O’Shea RS. Hepatitis C. Cleveland Clinic Foundation. diseasemanagement/hepatology/hepatitis-C/. Accessed August 10, 2011.
Centers for Disease Control and Prevention The ABCs of Hepatitis. Professionals/PDFs/ABCTable_BW.pdf. Accessed October 7, 2011.
Smith BD, Patel N, Beckett G, Ward JW. Hepatitis C virus antibody prevalence, correlates and predictors among persons born from through 1965, United States, Abstract #394. Presented at: American Association for the Study of Liver Disease 2011 Annual Meeting; San Francisco, CA; November 5, 2011.
Armstrong GL, Wasley A, Simard EP, McQuillan GM, Kuhnert WL, Alter MJ. The prevalence of hepatitis C virus infection in the United States, 1999 through Ann Intern Med. 2006;144(10):

5. Key Point
Baby boomers, the generation born between 1945 and 1965, have the highest rate of chronic hepatitis C virus (HCV) infection in the US; African Americans are disproportionately affected1,2
Notes
For African Americans, the rate of chronic HCV infection is 2 times the rate for Caucasians, 3% compared with 1.5%, respectively1
A recent analysis of National Health and Nutrition Examination Survey (NHANES) data suggested that baby boomers account for 82% of all chronic HCV cases in the US2
Within the baby boomer population the prevalence of HCV infection (measured by antibody prevalence) is:
5.5 times higher than in individuals born outside of this time period: 3.27% compared with 0.57%, respectively2
2-fold greater in African Americans (6.31%) than in Caucasians (2.92%)2
African Americans comprise 65% of the HCV-positive individuals within the baby boomer cohort2
The Centers for Disease Control and Prevention (CDC) is currently evaluating age-based screening, which may lead to updated HCV screening guidelines3
PCPs should be particularly vigilant about screening and diagnosis in populations with higher prevalence of HCV than the general population
References
Armstrong GL, Wasley A, Simard EP, McQuillan GM, Kuhnert WL, Alter MJ. The prevalence of hepatitis C virus infection in the United States, 1999 through Ann Intern Med. 2006;144(10):
Smith BD, Patel N, Beckett G, Ward JW. Hepatitis C virus antibody prevalence, correlates and predictors among persons born from 1945 through 1965, United States, Abstract #394. Presented at: American Association for the Study of Liver Disease 2011 Annual Meeting; San Francisco, CA; November 5, 2011.
CDC Foundation. Proposal: The Birth-Cohort Evaluation to Advance Screening and Testing for Hepatitis C (BEST-C). Accessed August 10, 2011

6. Key Point
The diagnosis of chronic hepatitis C virus (HCV) infection typically requires both an HCV antibody test and an HCV-RNA test. The combination of these 2 results allows for diagnosis of acute or chronic HCV infection, and to rule out any HCV infection1
Notes
The first diagnostic test for chronic HCV infection is an HCV antibody test on plasma or serum (requires a blood sample). This test will reveal the presence or absence of any exposure to HCV. The HCV antibody test is insufficient to diagnose chronic infection, as it only indicates exposure to HCV1
The presence of anti-HCV antibodies without the presence of HCV RNA* can indicate resolution of HCV infection (spontaneous or with treatment)1
HCV antibodies are not protective against future HCV infection2
Following a negative antibody test, if the patient is suspected of having acute infection or if they are severely immunocompromised, an HCV RNA test should be performed1
Antibodies to HCV can take between 4 and 10 weeks (average: 45 days) to develop following infection1
HCV RNA can be detected as early as 2-3 weeks after infection2
Severely immunocompromised individuals (eg, HIV infection, organ transplant, chemotherapy) may not generate enough antibodies to be detectable by an HCV antibody test1,2
The presence of HCV RNA coupled with a positive HCV antibody test indicates a current HCV infection1
The absence of both anti-HCV antibodies and HCV RNA indicates that no HCV infection has occurred1
*HCV RNA is the genetic material within the HCV virus.
RNA=ribonucleic acid; HIV=human immunodeficiency virus.
Reference
Ghany MG, Strader DB, Thomas DL, Seeff LB. Diagnosis, management, and treatment of hepatitis C: an update. Hepatology. 2009;49:
Centers for Disease Control and Prevention. Hepatitis C FAQs for Health Professionals Accessed August 9, 2011.

7. Key Point
The majority of hepatitis C virus (HCV)-infected individuals are untreated1
Notes
A retrospective analysis of a national population-based automated claims database estimated that HCV treatment rates are only ~30%1
Based on this estimate and the rate of HCV diagnosis, for every 100 patients with HCV, 25 are diagnosed2 and of those, only ~7 have ever been treated1
A number of barriers may limit patient linkage to care:
Many patients have limited health insurance coverage and access to medical care. In addition, the asymptomatic nature of HCV infection may make patients unlikely to pursue treatment 2,3
Healthcare providers may have limited education about HCV, making them uncomfortable about answering patient follow-up questions. Following diagnosis, clinicians may be unsure of the appropriate next steps, including those for patient counseling and referral1,3
Healthcare delivery systems may be deficient in linking screening to referral due to differences in available resources and HCV awareness/educational practices1,3
Primary care providers (PCPs) play a critical role in HCV screening, early diagnosis, and referral for treatment4
PCPs can collaborate with physicians experienced in treating and managing HCV-infected patients to help identify the best approaches for diagnosis and follow-up
References
Shatin D, Schech SD, Patel K, McHutchison JG. Population-based hepatitis C surveillance and treatment in a national managed care organization. Am J Manag Care. 2004;10:
Institute of Medicine. Hepatitis and Liver Cancer: A National Strategy for Prevention and Control of Hepatitis B and C. Washington, DC: The National Academies Press; 2010.
United States Department of Health and Human Services. Combating the Silent Epidemic of Viral Hepatitis: Action Plan for the Prevention, Care & Treatment of Viral Hepatitis
Ferrante JM, Winston DG, Chen PH, de la Torre AN. Family physicians' knowledge and screening of chronic hepatitis and liver cancer. Fam Med. 2008;40(5):

8. Summary
Identifying individuals at risk for HCV can be challenging for clinicians
HCV is transmitted by blood-to-blood contact, although many patients do not report a risk factor
Certain populations, including baby boomers and African Americans, have a higher prevalence of HCV infection than the general population
75% of infected individuals are not aware of their HCV status
HCV is diagnosed using an HCV antibody test and an HCV RNA test; PCPs should be vigilant about screening populations that have a higher prevalence of HCV infection than the general population
PCPs can collaborate with physicians experienced in treating and managing HCV-infected patients to help identify the best approaches for diagnosis and follow-up
HCV=hepatitis C virus; RNA=ribonucleic acid; PCP=primary care provider.