HIV and AIDS
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Introduction AIDS was first recognised as a new condition in 1981. Since then around 40 million people worldwide have been infected with HIV, the virus which can lead to AIDS. About a third of them have died. However, developments in treatment since the mid-nineties have dramatically improved the life expectancy for those diagnosed with HIV in the UK.
Symptoms People with HIV may not have any symptoms at all while they are in the latent phase. However, many people experience symptoms in the first couple of months after getting infected. These symptoms may include high temperature and fever, fatigue, skin rash, muscle pains, headache, nausea, vomiting and diarrhoea. But, if you have any of these symptoms, it is worth remembering that all of them are also symptoms of much simpler and less threatening conditions, such as flu. Once someone becomes ill with HIV, they are open to many infections. These can include infections of the mouth, such as thrush (oral candidiasis), unusual types of pneumonia, tuberculosis (TB), infections of the brain and eyes, unusual skin problems and odd infections of the gastrointestinal tract. Most people with severe HIV infection also experience weight loss, enlargement of their lymph glands and persistent diarrhoea.
Causes Once the HIV virus enters the body, it seeks out a type of white blood cells called helper T-lymphocytes. These usually defend the body against infection. The virus takes over the T-lymphocyte, causing it to die and releasing billions of copies of the virus back into the blood. These new viruses attach themselves to new T-lymphocytes and so the infection spreads. For a while, the body manages to keep producing enough T-lymphocytes to keep the immune system working properly. This is sometimes called the "latent phase". But, after some time (usually several years, sometimes as long as fifteen) and without effective treatment, the body reaches a stage where it cannot keep up with the HIV. Then, the immune system starts to fail and the person starts to become susceptible to other infections which would not normally make them ill. The person is now said to have AIDS.
Diagnosis HIV infection is diagnosed with a blood test (hence the term HIV positive). However, the test used in most UK hospitals will only show the presence of the virus once it has become established (three months or so after infection). Blood tests for HIV are very accurate; if there is any doubt about the result, the person will be asked to take another test. Anyone taking an HIV test should be informed of the implications of the test, and have a chance to talk things through if they want to. This is because a positive result (showing HIV infection) can have wide-ranging consequences for a persons life and relationships. Testing can be done either by a GP (family doctor) or in a specialist GUM (genito-urinary medicine) clinic. GPs may be asked to disclose details of test results to insurance companies and others making health checks on an individual, but tests in GUM clinics are subject to stronger legal confidentiality rules. You do not need to be referred by your GP to have a test at the GUM clinic. All pregnant women in England should be offered and recommended an HIV test as part of their routine antenatal care. If infection is diagnosed, there are a number of steps that can be taken to help reduce the likelihood of passing the infection to their baby. These include the use of antiretroviral drugs for the mother and her newborn baby, giving birth by Caesarean section and avoiding breastfeeding. Before treatment was available, many people felt there was little advantage in knowing whether they had HIV. Nowadays, testing means that someone can monitor their health and use treatments when they need to (usually not for several years after infection) to keep themselves well. AIDS is only diagnosed on the basis of an AIDS-related condition (such as an unusual infection normally only contracted by those with damaged immunity) in the presence of a positive HIV result. Sometimes people are only aware of the fact that they have HIV when they develop an AIDS-related illness and then have the HIV test. Treatment can still be effective at this stage, but some people still die every year in the UK because they did not know they had HIV until it was too late.
Treatment The treatment of HIV and AIDS is a specialised area that includes treatment to suppress the virus, treatment of conditions resulting from the virus, and emotional and psychological support for the individual and his or her family. Most treatment is done by specialists in HIV or GUM (genito-urinary medicine) clinics, although increasingly GPs are involved in the care of people with HIV. Medication for HIV falls into two main categories. The first is what is called combination therapy. This is usually started when there are clear signs that a persons immune system is reaching dangerously low levels. It works to suppress the virus and maintain the persons immunity as far as possible. There are now a number of these anti-HIV drugs (often called anti-retroviral drugs) which are given in combination and have dramatically improved the life expectancy of someone diagnosed with HIV. However, the treatments are complex and probably need to be taken for the rest of someones life, and can have serious side effects. Which ones to take and when to start taking them varies according to individual circumstances and is best discussed with a specialist. The second type of treatment involves the treatments required for any AIDS-related illnesses that arise. These will vary according to the condition diagnosed. For many people, testing and appropriate combination therapy treatment may avoid the need for treatment of this kind. Other support available includes dieticians, physiotherapists, counsellors, and a wide range of social care and peer support services from voluntary organisations. Prevention During vaginal or anal sex, the best way to stop HIV being passed on is to use condoms, if there is any possibility that either partner could have the virus. It can take only a single episode of unprotected intercourse (i.e. not using a condom) with an infected partner for HIV to be passed on. However, HIV is not always passed on the first time, so its never too late to start practising safer sex. Other preventative measures include not sharing needles if you are injecting drugs, and avoiding a blood transfusion in any country that does not screen and treat blood.
Glossary Blood Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.
Brain The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.
Immune system The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.
Lymph node Lymph nodes are small oval tissues that remove unwanted bacteria and particles from the body. Part of the immune system.
Caesarean A caesarean section is an operation to deliver a baby by cutting through the mothers abdomen to open the womb.
White cell White blood cells are the part of blood that fight infection and disease.
Blood test During a blood test, a sample of blood is taken from a vein using a needle, so it can be examined in a laboratory.
Blood transfusion A blood transfusion involves transferring blood into a person using a tube that goes directly into a vein in the arm.
Fatigue Fatigue is extreme tiredness and lack of energy.
High temperature A high temperature, also known as a fever, is when someone's body temperature goes above the normal 37C (98.6F).
Vomit Vomiting is when you bring up the contents of your stomach through your mouth.
Diarrhoea Diarrhoea is the passing of frequent watery stools when you go to the toilet.
Nausea Nausea is when you feel like you are going to be sick.
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