1. What is Hepatitis C?
Hepatitis C is a liver inflammation caused by a virus (hepatitis C virus or HCV), that when chronic can lead to cirrhosis, liver failure and cancer. It is known as the ‘silent’ epidemic due to the increased number of chronically infected people worldwide and the fact that the infected may not show any symptoms for 10 or 20 years, and feel perfectly healthy.
It is estimated that there are 170 million chronic carriers (about 3% of the world’s population), nine of which are European, which makes HCV a much more common virus than HIV, responsible for AIDS. According to the World Health Organization, it is possible that every year three to four million new cases arise on the planet.
The prevalence of the virus differs depending on geographical region; while in Europe and North America infection rates are around 2%, in Africa, Southeast Asia, the Western Pacific and Eastern Mediterranean prevalence rates are higher.
In the western world, users of injectable and inhalable drugs and people who have undergone blood transfusions and derivatives and/or surgery before 1992 are the most affected.
With the discovery of the human immunodeficiency virus – responsible for AIDS – in the 80s of the last century, new preventive measures were adopted and, today, the possibility of HCV infection through blood transfusion or during surgery in hospitals is practically null. This security is not guaranteed in some medical facilities and hospitals in developing countries.
In Portugal, chronic hepatitis C is already a major cause of cirrhosis and hepatocellular carcinoma; there are an estimated 150,000 people infected, although the vast majority are undiagnosed.
According to a study by the European Monitoring Centre for Drugs and Drug Addiction, Portugal is one of the European countries with the highest rates of this virus’ infection, which affects 60 to 80% of drug addicts.
About 20 to 30% of individuals infected with HCV recover spontaneously after an acute infection from HCV, but the remaining 70 to 80% progress to chronic hepatitis, often without even realizing it. In 20% of patients, chronic hepatitis C can lead to cirrhosis and/or liver cancer.
Some patients may develop cirrhosis within a few years, while others may take decades. Among the possible explanations are the age at which the person was contaminated (the later it was, the more serious the evolution of infection may be), hormonal differences (more common in males) and alcohol consumption (which stimulates the multiplication of the virus and decreases immune defences).
This type of hepatitis only exceptionally presents itself as fulminant hepatitis.
2. What causes Hepatitis C?
Hepatitis C is caused by a virus, more specifically the hepatitis C virus or HCV. This virus was only identified in 1989 and accounts for about 90% of so-called hepatitis non-A and non-B.
The incubation period is an average of six to seven weeks. About 85% of individuals who have contracted HCV become chronically infected. Of these, about 70% develop chronic hepatitis. About 20% to 25% of chronic hepatitis caused by HCV progress to liver cirrhosis, and in cirrhotic patients about 1-5% develop primary liver cancer. The mortality rate from chronic HCV hepatitis is estimated to be between 1% and 5%.
Important factors in aggravation and acceleration of lesions in chronic hepatitis:
- Consuming alcoholic beverages;
- Co-infection with other viruses (HIV, HAV, HBV);
- Previous or concomitant liver disease.
3. How can I contract Hepatitis C?
Hepatitis C is transmitted primarily through contact with the blood of an infected person, and, with much less efficiency, through body fluids. The virus has also been detected in saliva, urine, semen and bile, but with a low potential risk of transmission.
Therefore, HCV is essentially spread through contaminated blood.
Risk situations, with different contagion potentials:
- Sharing syringes and other instruments used in the preparation of injecting and inhaling drugs;
- Blood exposure from cutting or perforating materials of collective use improperly sterilized or disposable, used in procedures such as body piercing, tattoos, acupuncture, manicures/pedicures, barbers and hairdressers, etc.;
- Social or familial contact with personal items (toothbrushes, razors, shavers, scissors, etc.);
- Healthcare professionals’ occupational exposure to blood (needles, needlestick injuries);
- Not using condoms during sexual intercourse when there are multiple partners. However, as the sexual transmission is infrequent, its use in relations between spouses is not usually required;
- Newborns from HCV positive mothers;
In the absence of a vaccine against hepatitis C, it is best to focus on prevention, avoiding, above all, contact with contaminated blood.
4. What are the symptoms of Hepatitis C?
In most cases, this disease is asymptomatic, which further complicates its control and facilitates its spread in the community. The diagnosis is generally accidental, being made during serological screening in blood donations, or to assess the possible cause of altered transaminases, evidenced in routine examinations.
Only 25 to 30% of those infected exhibit, in the acute phase, symptoms of illness, which can manifest itself through unspecific complaints such as lethargy, malaise, fever, concentration problems; gastrointestinal complaints such as loss of appetite, nausea, alcohol intolerance, liver pain, or the more specific symptom, jaundice.
Often, the symptoms are unclear and may resemble the flu. The chronic carrier of the virus may not have any symptoms, feeling healthy, while developing cirrhosis or liver cancer.
5. Which tests are done to diagnose Hepatitis C?
Hepatitis C infects and damages the liver. In response to exposure to the virus, our organism produces antibodies against HCV proteins. The most common test for HCV surveys these antibodies in our blood. Other available tests detect the presence of viral RNA, the amount of RNA present, or determine the specific subtype of the virus.
Each test has a slightly different purpose:
- Anti-HCV tests detect the presence of antibodies against proteins of the virus, indicating exposure to HCV. These tests do not distinguish whether the tested subject still has an acute or chronic active viral infection, or whether it is a serological scar that has simply been exposed to the virus in the past.
Generally, the test is reported as positive or negative. There is some evidence that if the test is weakly positive, it may not mean previous exposure to HCV. The weakly positive results should be confirmed with the next test.
- HCV RIBA test (immunoblotting) is an additional test to confirm the presence of antibodies against the virus. In most cases, it can tell us if the positive anti-HCV test was due to exposure to HCV (positive RIBA) or it represents a false signal (negative RIBA).
In a few cases, the results fail to answer this question (Undetermined RIBA). Like the anti-HCV test, the RIBA cannot tell us if the subject is currently infected, only that there was an exposure to the virus.
- HCV-RNA testing is carried out by polymerase chain reaction (PCR) and detects the RNA of the Hepatitis C virus, indicating whether there is an active HCV infection. The result of the HCV-RNA is considered positive if a viral RNA is detected; otherwise, the result is negative.
In addition to its application as a confirmation test, the Qualitative HCV-RNA can also be used to control treatment response, verifying if the virus was eliminated from the body after treatment.
- Viral Load or Quantitative HCV-RNA tests measure the number of viral RNA particles in the blood. Viral load tests are often used before and during treatment to help determine response to the therapy, by comparing the amount of virus before and after the treatment (typically 3 months).
- Viral Genotyping is used to determine the type, or genotype, of the virus. There are 6 major HCV types; the most common (genotype 1) have a worse response to treatment than genotypes 2 and 3 and usually requires longer therapy (12 months versus 6 months for genotypes 2 and 3).
Determining the HCV genotype is, therefore, useful to define a treatment strategy, being solicited before starting treatment to assess its success and required duration.
6. What does the test result mean?
If the result of the Anti-HCV test is positive, it means that you were likely infected with the Hepatitis C virus, even if the infection has been so faint that you were not even aware of it.
A positive anti-HCV test should be confirmed by an HCV RIBA test, especially if the result is weakly positive. A positive RIBA confirms that you have been exposed to the virus, while a negative RIBA indicates that your first test was probably a false positive and you have never been infected with HCV.
An HCV RNA Qualitative test is often used when the antibody test is positive, to verify whether the infection is still present. A positive HCV-RNA means that you are currently infected with HCV.
Currently, the RIBA tests have been receiving increasingly restricted indications in clinical practice, since when faced with a positive anti-HCV result, through enzyme immunoassay testing, the most favourable procedure from the standpoint of cost-effectiveness appears to be Qualitative HCV-RNA survey, which not only confirms the positivity of the antibody but also determines the presence of current viremia.
7. Can I be vaccinated against HCV?
No. There is currently no vaccine available.
Developing a vaccine has been difficult because the virus displays several different molecular configurations that are constantly changing. In addition, antibodies raised by HCV infection are not neutralizing, meaning they do not prevent reinfection or grant immunity. The difficulty in the development of the vaccine against the virus stems mainly from this behaviour of the immune system when faced with HCV infection.
8. Is there a treatment for Hepatitis C?
Yes, there are currently certain drugs that can be used in the treatment of HCV infection. The most commonly used is a combination of two drugs (pegylated interferon associated with ribavirin).
Meanwhile, the effectiveness of the treatment depends on various factors such as age, the virus’ genotype and the viral load exhibited by the HCV, and the degree of liver damage. Healing probabilities can, therefore, vary from very low to as high as 80%.
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