Signs and symptoms of hepatitis C virus infection
About 3.2 million people have chronic HCV infection, and more than half are unaware of their condition.
In the wake of recent breakthroughs in the management of hepatitis C virus (HCV) infection, with several new promising medications available on the market and more being studied in clinical trials, it may now be possible to imagine a cure for this disease. Barriers and challenges, such as difficulty in reaching high-risk populations, the stigma of the disease, provider reluctance to assess risk factors, and patient reluctance to admit high-risk behaviors, may delay the identification of persons infected with HCV.1
Communication between healthcare providers and patients, including promoting awareness of HCV infection and emphasizing the screening of high-risk populations, is crucial in diagnosis. This article discusses the current epidemiology, risk factors, pathophysiology, diagnosis, management, and prognosis of HCV infection.
Epidemiology and risk factors
According to the World Health Organization (WHO), approximately 3% of the world's population is infected with HCV, and more than 170 million chronic carriers are at risk for liver cirrhosis and hepatocellular carcinoma, which are complications of HCV infection.2 In the United States, approximately 30,000 new cases of HCV infection develop yearly; about 3.2 million individuals have chronic HCV infection, and an estimated 50% to 70% of them are unaware of their condition.1,3
Chronic HCV infection is the leading cause of liver-related death and reason for liver transplant in the United States, and it has recently eclipsed human immunodeficiency virus (HIV) infection as a cause of death.4 The HCV infection mortality rate is 4.58 per 100,000 people per year, and almost 75% of deaths occur among adults aged 45 to 64 years. In the Third National Health and Nutrition Examination Survey (NHANES III), neither gender nor race/ethnicity was independently associated with HCV infection.2
There is considerable variation in the geographical distribution of the 6 HCV genotypes. Genotype 1 accounts for approximately 70% and genotypes 2 and 3 for approximately 30% of the HCV-infected population in the United States.5 Genotype 4 is typically found in Africa and the Middle East and is rare in the United States. Genotypes 5 and 6 are mostly confined to South Africa and Southeast Asia, respectively.6 Genotype is not a predictor of outcome but is important in selecting a genotype-specific therapeutic regimen, determining the duration of treatment, and predicting the likelihood of a response to treatment.5
The transmission of HCV in infected blood or body fluids via the parenteral route is associated with multiple risk factors (Table 1). Additional risk factors include intranasal cocaine use, body tattooing or piercing with unsterilized equipment, occupational exposure (eg, healthcare workers), and household exposure (eg, sharing razors or toothbrushes).
Recent reports highlight a new cohort of injection drug users with HCV infection: white, urban dwellers aged 24 years or younger who have used oral prescription opiates before heroin.7 Patients who are HIV-positive are also at risk for HCV transmission, as the risks for transmitting HCV and HIV are identical. Many HCV-positive patients are unable to identify a source of infection.