AIDS stands for Acquired Immuno Deficiency Syndrome are caused by HIV (human immunodeficiency virus).

The virus attacks the immune system particularly the CD4 cells and make the individual prone to opportunistic infections, which attack the human body when the immune system goes down. These so called opportunistic infections are uncommon or rare in healthy individuals who have a good immune defence mechanism.

Modes of transmission

  • Unprotected sex - that is, sex without a condom. The risk seems to be higher from men to omen, and to the passive partner in anal intercourse than vice versa.
  • Blood-to-blood-infection when using a contaminated needle in drug addicts or through transfusions of contaminated blood. Today, all blood that is donated in the UK is tested for HIV so this route of infection is extremely unusual.
  • Mother infecting her child. The child can be infected during the pregnancy, during labour or, after the delivery, through the breast milk.

Ordinary social interaction with HIV-positive people is not contagious

At the start of HIV infection - the primary HIV infection one can have a short, flu-like illness that occurs one to six weeks after infection or no symptoms at all. Symptoms may include fever, joint pain, muscle pain, sore throat, feeling of run down, and a faint pink rash. However, even if you do not have any symptoms you can still infect other people.

Six to 12 weeks after the infection, the white blood cells have produced so many antibodies against HIV that they can be measured in the blood.

If you have HIV antibodies in your blood, you are HIV-positive (HIV+). The infected person will feel well for a long time, but the infection is still active inside the body.

Once the HIV virus has killed so many T-helper cells, the immune system is no longer able to recognise and react to attacks from everyday infections.

A number of different symptoms can be observed:

  • Fatigue.
  • Inexplicable weight loss.
  • Repeated bronchial and skin infections that do not react to normal treatment.
  • Fever.
  • Swollen nodes.
  • Diarrhoea
  • Small, deep ulcers often preceded by small blisters.
  • Night sweats.
  • Outbreak of previous infections that have remained dormant (herpes, toxoplasmosis, shingles and other conditions).
  • So called 'opportunistic infections' - serious infections by micro-organisms of the type normally prevented by the immune system. These in turn could lead to a number of related illnesses such as cancer or dementia.
  • In the end, the disease can become so serious that the infected patient dies.

Risk factors for infection

  • People who do not practise safe sex including wearing condoms, especially if their partners originate from areas of the world where HIV is widespread - Africa (south of the Sahara Desert), Asia and the Caribbean Islands.
  • Homosexual and bisexual men who do who not practise safe sex and have many different partners.
  • Women who have unprotected sex with many different partners, especially if these include bisexual men.
  • Men who have unprotected sex with many different partners.
  • Prostitutes who do not practise safe sex. Also at risk are their customers and these customers' other sexual partners.
  • Relationships in which one or both of the partners have many different partners.
  • Drug addicts who share needles.
  • Hospital workers who are at risk of pricking or cutting themselves with infected instruments or needles.
  • Children with an HIV-infected mother.
  • People who have had many blood transfusions or who were treated with blood products before 1985.

Factors that would minimise the risk greatly

  • Use a condom. This is not a guaranteed method of avoiding infection, but using a condom reduces the risk considerably.
  • Avoid using drugs that are injected with a syringe. Do not share syringes or needles with others.
  • Avoid blood transfusions in certain countries where they may not test the blood for HIV.
  • People who have already been infected with HIV or belong to high-risk groups should not donate blood, sperm, or organs.
  • Even if you have tested negative you could still be infected with the HIV virus. You may not have produced enough antibodies to indicate infection or were infected after the blood sample for the test was taken.

Some of the AIDS defining conditions

  • Candidiasis infecting the lungs, trachea, oesophagus
  • Coccidioidomycosis
  • Cryptococcosis
  • Cryptosporodiosis
  • Cytomegalovirus retinitis which might lead to blindness
  • Histoplasmosis
  • Kaposi sarcoma
  • Lymphoma
  • Pnemocystitis carinii pneumonia
  • Progressive multifocal leukoencephalopathy {PML}
  • Salmonella septicaemia
  • Toxoplasmosis of the brain
  • Excessive weight loss, otherwise known as “wasting syndrome”.

If you think you might be infected
If you have been exposed to infection, you should contact your doctor as soon as possible for advice, testing and treatment. In most cases, the doctor might advise you to be tested approximately three months after the possible time of infection.
If you have recently been exposed to infection or have any of the symptoms connected with primary HIV infection, you will be offered a test that checks both antibodies and the HIV virus itself. In some instances of early HIV infection, the treatment is started at this very early stage.
If you know or suspect that your partner is HIV-positive or if you have been exposed to infection by accident - for instance through pricking yourself with a needle - in some cases, a treatment will be started that aims to prevent an actual HIV infection. This preventive treatment should preferably be started a few hours after the time of exposure. The treatment may have some unpleasant side effects, so before going ahead the real risk of infection should be estimated.
Places to get tested An HIV test is free of charge and anonymous. You can be tested:
  • At clinics dealing with skin and venereal diseases
  • At special clinics for HIV screening.

In some cases, testing is obligatory. You are required to have a test if you want to do any of the following:

  • Become a blood donor.
  • Donate some of your organs for transplantation
  • Use your sperm for artificial insemination
  • Adopt a child or have egg transplantation.


New and more efficient treatments to fight HIV and reduce the content of virus in the blood are being developed all the time.

Unfortunately, HIV is a very efficient virus that can change some of its own characteristics, mutate and create new HIV variants, which are resistant to the medicines used in treatment. To reduce the risk of developing resistance to the medication and fight the virus from several directions, you will be offered a treatment that includes several types of medication. These are:

Antiviral medications against the HIV virus, that stops the virus from spreading in the body. You will not be cured and you are still contagious. But it greatly reduces the chances of opportunistic infections. It is still not known how long the effects of the treatment will last.

  • Specific treatment of infections occurring as a result of HIV.
  • Vaccination against illnesses such as flu, pneumonia, and infectious hepatitis.
  • Treatment of the symptoms connected with HIV infection and AIDS, for instance treatment of nausea and loss of appetite.

Eventually, serious illnesses may develop as a result of HIV infection. Commonly, these include infections of the kind normally prevented by the immune system:

  • Tuberculosis
  • Pneumonia with Pneumocystis carinii
  • Toxoplasmosis in the brain
  • Reactivation of cytomegalovirus
  • Infections involving the fungus Candida albicans
  • Cancer, especially skin cancer and cancer in the lymph nodes
  • Meningitis and encephalopathy, a brain disease which causes dementia.
  • Death may occur as a result of illness.

Please consult the online doctor for bespoke, evidence based and confidential medical advice.