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Hepatitis C
Hepatitis means inflammation of the liver. There are several different Hepatitis viruses, namely A, B, C, D, E and G. But there are important difference in the way they are spread and the amount of liver damage they cause. The commonest viruses associated with injecting drug users are Hepatitis B and C. Both are spread primarily through blood to blood contact.
Hepatitis C is more infectious than HIV but not as infectious as Hepatitis B. Whereas most people recover from Hepatitis B and only around 10% go onto suffer long term liver damage, Hepatitis C becomes chronic in 80% of infected people. However, it can take many years for liver damage to develop. Most people have minor liver damage but around 25% may progress to serious chronic liver disease.
Hepatitis C The Hepatitis C virus, also known as HCV or hep C, is thought to be primarily transmitted through blood and may cause inflammation of the liver. The virus has been found in other body fluids such as saliva but it is not clear whether these fluids can actually transmit the virus. The virus was first called non-A non-B Hepatitis and was given the name Hepatitis C in 1989 when a test to detect antibodies became available. Blood donations have been screened for the virus since September 1991 which means the risk of infection through transfusions or blood products is now minimal. This leaves injecting drug users as the main source of new infections. Users are thought to become infected by sharing contaminated injecting equipment.
Prevalence The prevalence of Hepatitis C on a global scale is largely unknown simply because most people have no symptoms when they first become infected, so can infect others unknowingly. The World Health Organisation estimates that 3% of the world's population has Hepatitis C and that 200 million people are chronically infected.
In a national survey of 2,000 injecting drug users 60% were found to be infected. The rates of infection in London and Scotland are higher than the rest of the UK, which is the same pattern for HIV. The prevalence is high in prisons because of the ready availability of drugs and shared equipment. In Australia the prevalence among long term users approaches 100%. Around the world the rates have been shown to range from 57% to 86%. These figures are unlikely to reflect the whole picture as many people do not know they are infected.
Genotypes There are several recognized strains of Hepatitis C, known as genotypes with numerous subtypes. The prevalence of different genotypes varies from country to country. The most common genotypes in the UK, Europe and USA are 1, 2 and 3. Subtypes are labeled a, b and c. It is possible for users who continue high risk practices to be reinfected with a different genotype, or be infected with two strains at the same time. That is why it is important to always practice safe injecting practices, even if you think that you may be infected.
How is Hepatitis C transmitted? The virus is transmitted through blood to blood contact. There have been many studies to determine whether Hepatitis C is sexually transmitted.. It can certainly occur but it seems to be unusual. There are a few cases of Hepatitis C being spread through other body fluids such as saliva but the risk is thought to be low. Experts are unsure whether infection occurs between partners because of sexual exposure or because of sharing a personal item such as a toothbrush or razor.
Infection is not thought to be acquired through normal social contact. For example, you cannot catch it from sharing a toilet seat or cup or just touching an infected person. Washing cutlery and crockery in hot water and washing up liquid is thought to be safe. There are varying estimates, from 10 to 45% of people with chronic Hepatitis C, who do not know how they caught it. However, many doctors believe that in most of these cases, careful questioning will reveal a past experience with injecting drugs. Only one occasion of sharing is needed to be potentially exposed to the virus.
Among injecting drug users Hepatitis C has spread rapidly through the injecting drug community. Many drug users will say that they do not share but their initial experiences of injecting are usually with a friend's encouragement and borrowed works. Or they more than likely will have shared other equipment, as many times the friend will have cooked up their first hit for them using their water, spoon, etc. Some people who inject steroids, such as bodybuilders, don't consider themselves as injecting drug users and don't consider sharing with friends as risky. They mistakenly believe that blood borne viruses only infect so called 'junkies'.
Occasional users are more likely to share a friends equipment because the drug use is unplanned. Some drug users think that sharing with long term partners isn't risky. Yet the infection may take many years before symptoms develop and people who only injected during the 1960s are now presenting with Hepatitis C and liver disease. Long term users who usually use needle exchanges also share from time to time.
Most users will know that it is unsafe to share needles but they may be unaware that sharing any injecting equipment (filters, water, spoons, tourniquets, etc.) is just as unsafe. Some of their injecting practices, such as flushing out, front & backloading and skin popping are also unsafe and carry a high risk of infection. Many users don't regard front & backloading as sharing but there is a risk if either syringe is contaminated with the virus. If a needle, syringe, water, filter, spoon or anything used is shared without adequate cleaning, it is likely to contain blood which will be injected into the next person.
Safer Injecting By far the best advice for someone who continues to inject is that they should not share any injecting equipment. They should use a new set of clean works from a needle exchange or their own clean works every time. If they find themselves in a situation where they do not have any clean works and they are going to use old works, they must always clean the equipment. This will minimise the risk of being infected but does not guarantee protection. See the Cleaning instructions under the Safer Injecting Guide.
Mother to Baby - Vertical Transmission The risk of a mother infecting her baby during pregnancy or birth is low. However, the risk increases if the mother is also HIV positive. Mothers who have high levels of the virus in their blood have a greater chance of transmitting the infection to their baby. It is still not known whether this happens during pregnancy (in utero), or during or immediately after the birth (perinatally). But it is thought that it is perinatally and doctors can therefore carry out a 'blood free' delivery, which usually guarantees that the baby will not be infected. This is why it is vital that you inform the medical staff looking after you, if you know or think you may be infected.
Antibodies to Hepatitis C are sometimes found in babies born to positive mothers but they usually disappear by twelve months after the birth, which shows that they are maternal antibodies acquired from the mother. Testing of infants should therefore, be deferred until after one year of age.
Breastfeeding The virus has been found in breast milk but there are no reported instances of babies being infected through breastfeeding. Theoretically it may be a problem if a mother has cracked nipples, which bleed or a baby has a cut in its mouth. As each case is individual and research is ongoing, specialist advice should be sought at the time of the birth.
Infected mothers should be careful after the birth not to use their own personal objects such as toothbrushes, nailbrushes and scissors for their baby and any blood spills should be carefully mopped up with household bleach.
Main Ways of Infection
How can I avoid getting Hepatitis C?
What illness can Hepatitis C cause? Hepatitis C infection can affect people quite differently. The majority of people have no symptoms and are often unaware they have been infected. The commonest complaint is extreme tiredness and generally feeling unwell. Symptoms, when present, may be vague and include:
Some of the symptoms come and go and it is not unusual for people to be diagnosed with ME.
Hepatitis C is difficult to diagnose in drug users by symptoms as the less specific complaints are not unusual and could be caused by their drug use or alcohol consumption. An episode of acute Hepatitis with jaundice is unusual in the early stages of the disease. Bleeding and liver failure may only occur in the late stages of the disease when cirrhosis is established.
The liver is a very uncomplaining organ and most people do not know that it is not working properly until more advanced liver disease has developed. There is usually a long latent phase in which people feel quite well and before more serious liver disease becomes apparent. Hepatitis C infection in combination with HIV or Hepatitis B, may progress more quickly to chronic liver disease. Rapid progression often occurs in heavy drinkers. Drug users who do not have antibodies to Hepatitis B should consider being vaccinated to prevent co-infection and be advised to drink as little alcohol as possible. Some doctors will advocate complete abstinence. Hepatitis A vaccination is also sometimes recommended, as an attack of Hepatitis A on top of pre-existing liver disease may be fatal.
Hepatitis C is regarded as chronic when it has lasted longer than six months. The liver remains inflamed and causes damage to the liver cells.
Cirrhosis Cirrhosis is the result of long term continuous liver damage. Normally, when the liver is damaged the cells die and the liver regrows without scarring. When the damage is severe and continuous, the regrowth results in cirrhosis. Cirrhosis is irreversible. If cirrhosis is advanced some people develop complications such as ascites, bleeding oesophageal varices and encephalopathy. Ascites is a build-up of fluid in the abdomen and oesophageal varices are varicose veins in the gullet caused by increased blood pressure in these veins. Encephalopathy is impaired mental function and is thought to be caused by waste products which are normally broken down by the liver, entering the circulation and affecting the brain. A further complication can be liver cancer.
Tests An antibody test for Hepatitis C is a blood test, sometimes called an anti HCV test. Currently the most widely used test is an ELISA-3 (third generation enzyme linked immunosorbent assay). Anti HCV positive is a positive result and only indicates that a person has been exposed to the virus at sometime in their life. A further test is needed to detect ongoing infection. A positive ELISA test is usually confirmed by a RIBA test.
A blood test called a PCR (polymerase chain reaction) is a more sensitive and specific test. It detects the viral genetic material and indicates an active infection. Using modifications to the test it is possible to determine the strain of HCV and the amount of virus in the blood. However, the tests are not always conclusive and sometimes have to be repeated. A negative PCR test does not necessarily mean that someone no longer has Hepatitis C. It can mean that the virus is at a very low level and therefore at an undetectable level in the blood.
The results of these tests can be confusing unless clearly explained by a specialist.
Seroconversion It can take up to six months for antibodies be detected in the blood. This is sometimes referred to as seroconversion or the window period. It is important for users who keep sharing to be retested approximately six months after their last suspected risk.
Liver Function Tests Liver function tests (LFTs) are blood tests which measure enzymes and other substances released into the bloodstream when the liver cells are damaged. They give doctors an indication of liver disease but do not detect the presence of the virus. Raised enzymes are common in Hepatitis C infection but the levels can fluctuate throughout the course of the disease. Sometimes they can be within normal levels but this does not mean that liver disease is absent. The tests are performed regularly and need specialist interpretation.
Liver Biopsy A liver biopsy is nearly always performed to determine the extent of any damage. It is performed in hospital, usually under a local anesthetic. As cirrhosis can take years to develop and it is difficult to predict who will develop it, a biopsy is necessary to accurately assess the health of the liver and to determine whether treatment is likely to be effective.
Treatment Everyone with Hepatitis C should be referred to a specialist who has expert knowledge of Hepatitis. Not everyone with Hepatitis C needs or is suitable for treatment. Some only need regular monitoring by a specialist. The current treatment is with an antiviral drug called Alpha Interferon. It mimics naturally occurring interferon in the body which is produced as part of the body's immune response to infection. The aim of treatment is to prevent the virus replicating and causing further liver damage.
The drug is given by subcutaneous injection usually three times a week over a period of six to eighteen months and generally people are taught to inject themselves. Some people do not respond to treatment and may relapse as soon as treatment stops. Doctors are learning more about who is likely to respond and several factors may be taken into consideration before treatment is advised. Some of the factors are age, viral genotype and how long a person has been infected and whether cirrhosis has developed.
Interferon usually produces side effects which can be quite unpleasant. In the early stages many people experience flu like symptoms such as nausea, fatigue, sweats, muscle aches, headaches and depression. The severity of side effects varies from person to person and can often be helped by taking paracetomol. Some people who experience particularly bad side effects may be unable to tolerate a full course.
Combination treatment with interferon and other antiviral drugs looks promising and may improve the response rate. There is most experience with a drug called Ribavirin but other combination treatments are under trial.
It is important for infected people to be seen regularly by a specialist whether treatment is considered clinically appropriate or not. Regular assessment is needed to detect whether damage is occurring and if therapy is appropriate.
IF YOU HAVE HEPATITIS C INFECTION
Please DO NOT
Please DO
Remember that a negative test for Hepatitis C does not mean that you are immune to it and there are other types of Hepatitis that can be caught. If you continue to put yourself at risk, then you might become infected in the future. For further information and advice, speak to your family doctor who will be able to advise you and also put you into contact with specialists and organisations. Also look in your phone book for numbers of organisations that deal with Hepatitis.
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