HEPATITIS C VIRUS (HCV)
KEY FACTS AND OVERVIEW:
Hepatitis C is a liver infection caused by the hepatitis C virus (HCV) and spread through contact with blood from an infected person; sometimes leads to serious liver damage. Nowadays, most people become infected with HCV by sharing needles or other equipment used to prepare and inject drugs. People may also get HCV from unsafe health care, unscreened blood transfusions and sexual practices that lead to blood exposure. 
For some people, hepatitis C is a short-term illness, but for more than half of people who become infected with the HCV, it becomes a long-term, chronic infection. Long-term infection with the HCV is known as chronic hepatitis C and this can result in serious, even life-threatening health problems like cirrhosis and liver cancer. Antiviral medicines can cure >95% of people with HCV infection, but access to diagnosis and treatment is low. There is currently no effective vaccine against hepatitis C. Globally, an estimated 58 million people have HCV infection, with about 1.5 million new infections occurring per year. There are an estimated 3.2 million adolescents and children with chronic HCV infection. The best way to prevent hepatitis C is by avoiding behaviors that can spread the disease, especially injecting drugs. Getting tested for hepatitis C is important, because treatments can cure most people with hepatitis C in 8-12 weeks.
SYMPTOMS:
The incubation HCV period: 2 weeks to 6 months. Following initial infection, approximately 80% of people do not exhibit any symptoms. People with chronic hepatitis C can often have no symptoms and don't feel sick, as chronic hepatitis C is usually a "silent" infection for many years, until the virus damages the liver enough to cause the signs and symptoms of liver disease. Signs and symptoms include:
- bleeding and bruising easily
- fatigue and poor appetite
- yellow discoloration of the skin and eyes (jaundice)
- dark-colored urine
- itchy skin and weight loss, swelling in the legs
- fluid buildup in the abdomen (ascites)
- confusion, drowsiness and slurred speech (hepatic encephalopathy)
- spiderlike blood vessels on the skin (spider angiomas)
Acute HCV infection doesn't always become chronic. Of those with chronic HCV infection, the risk of cirrhosis ranges from 15% to 30% within 20 years.
CAUSES:
Hepatitis C infection is caused by the HCV and spreads when blood contaminated with the virus enters the bloodstream of an uninfected person.
Globally, HCV exists in several distinct forms, known as genotypes. Seven distinct HCV genotypes and more than 67 subtypes have been identified. The most common HCV genotype in the United States is type 1. Although chronic hepatitis C follows a similar course regardless of the genotype of the infecting virus, treatment recommendations vary depending on the viral genotype.
COMPLICATIONS:
HCV infection that continues over many years can cause significant complications, such as:
- Scarring of the liver (cirrhosis). After decades of HCV infection, cirrhosis may occur. Scarring in your liver makes it difficult for your liver to function.
- Liver cancer. A small number of people with HCV infection may develop liver cancer.
- Liver failure. Advanced cirrhosis may cause your liver to stop functioning.
GEOGRAPHICAL DISTRIBUTION:
HCV infections may occur in all regions. The highest burden of disease is in the Eastern Mediterranean and European Regions, as well as the South-East Asia and the Western Pacific Regions. Millions of people are chronically infected in the African Region and a couple millions also in the Region of the Americas.
TRANSMISSION:
The HCV is a bloodborne virus, commonly transmitted through:
- the reuse or inadequate sterilization of medical equipment, especially syringes and needles in healthcare settings;
- the transfusion of unscreened blood and blood products;
- injecting drug use through the sharing of injection equipment.
HCV can be passed from an infected mother to her baby and via sexual practices that lead to exposure to blood (for example, people with multiple sexual partners and among men who have sex with men).
Hepatitis C is not spread through breast milk, food, water or casual contact such as hugging, kissing and sharing food or drinks with an infected person.
TESTING AND DIAGNOSIS:
Because new HCV infections are usually asymptomatic, few people are diagnosed when the infection is recent. In those who develop chronic HCV infection, this is often undiagnosed because it remains asymptomatic until decades after infection when symptoms develop secondary to serious liver damage.
HCV infection is diagnosed in 2 steps:
1. Testing for anti-HCV antibodies with a serological test identifies people who have been infected with the virus.
2. If the test is positive for anti-HCV antibodies, a nucleic acid test for HCV ribonucleic acid (RNA) is needed to confirm chronic infection and the need for treatment. This test is important because about 30% of people infected with HCV spontaneously clear the infection by a strong immune response without the need for treatment. Although no longer infected, they will still test positive for anti-HCV antibodies. This nucleic acid for HCV RNA can either be done in a lab or using a simple point-of-care machine in the clinic.
RT-PCR COUNTING HCV RNA IS THE MOST ACCURATE INFECTION INDICATOR.
After chronic HCV infection diagnosis, an assessment determines the degree of liver damage (fibrosis and cirrhosis). This can be done by liver biopsy or through a variety of non-invasive tests. The degree of liver damage is used to guide treatment decisions and disease management.
About 6.2% of the estimated number of people living with HIV globally have serological evidence of past or present HCV infection. Chronic liver disease represents a major cause of morbidity and mortality among people living with HIV globally.
TREATMENT:
A new infection with HCV does not always require treatment, as the immune response in some people will clear the infection. However, when HCV infection becomes chronic, treatment is necessary.
WHO recommends therapy with pan-genotypic direct-acting antivirals (DAAs) for all adults, adolescents and children <3 years old with chronic HCV infection. DAAs can cure most people with HCV infection, and treatment duration is short (usually 12-24 weeks), depending on the absence/presence of cirrhosis. In 2022, WHO included new recommendation for treatment of adolescents and children using the same pan-genotypic treatments used for adults.
Access to HCV treatment is improving but remains too limited. Of the million of people living with HCV infection globally, only an estimated 21% know their diagnosis, and of those diagnosed with chronic HCV infection, around 62% are treated with DAAs.
PREVENTION:
There is no effective vaccine against hepatitis C so prevention depends on reducing the risk of exposure.
Primary prevention interventions recommended by WHO include:
- safe and appropriate use of health care injections;
- safe handling and disposal of sharps and waste (raised caution regarding body piercing and tatooing);
- provision of comprehensive harm-reduction services to people who inject drugs;
- testing of donated blood for HBV and HCV (as well as HIV and syphilis);
- training of health personnel; and
- prevention of exposure to blood during sex.
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