AIDS stands for acquired immunodeficiency syndrome. It is caused by the human immunodeficiency virus (HIV).

HIV is transmitted through unprotected sexual intercourse. Blood-to-blood transmission is also possible, e.g. through contaminated syringes or transfusion of contaminated blood. The virus can be passed from mother to child during pregnancy.

In normal interaction with HIV positive people (shaking hands, kissing on the cheek, living in the same household etc.) there is no risk of infection.

Symptoms and signs

Scientists divide the disease into a number of stages.

The first stage is HIV infection. This can lead to flu-like symptoms in the first few weeks or be asymptomatic. By 6 – 12 weeks after the infection the white blood cells have usually formed so many antibodies that these can be detected in the blood. From then on the result of the HIV test is positive.

A person infected with HIV does not usually have any symptoms. However the virus multiplies and attacks more and more blood cells, causing the immune system to become weaker and weaker.

AIDS refers to the stage of the disease in which the immune system is so weakened that infectious diseases and tumors can develop. Without treatment, there is usually an interval of nine years from infection with HIV to manifestation of AIDS.

The first symptoms of AIDS are nonspecific, e.g.

	repeated occurrence of fever over 38.5 °C,
	night sweats,
	lymph node enlargement,
	diarrhea lasting longer than one month and having no other cause,
	fungal infection of the mouth and throat and/or of the genital organs,
	recurrent shingles,
	nervous disorders of arms and legs,
	cervical alterations,
	whitish, hairy-looking lesions on the oral mucosa.

As the disease progresses the patient's immune defenses become weaker and weaker and severe diseases of major organs can develop. These include tuberculosis, pneumonia and cancers.

Diagnosis

Diagnosis is made by detection of HIV antibodies in the blood.
If antibodies are present HIV must have entered the body. This is called a 'positive test'.

Prevention and treatment

The best protection against AIDS is safer sex. Drug users should not share needles. Health care workers who come into contact with body fluids should adhere strictly to all hygienic rules.

If you think you may have been infected with HIV you should see a doctor as soon as possible. Preventive treatment can still be initiated within a few hours after the potential infection.

AIDS cannot yet be cured. There are only drugs that can delay the manifestation of AIDS and improve the patients' life expectancy and quality of life.

There are a number of different treatment approaches, which are often combined with each other.

	• Use of antiviral drugs which inhibit the spread of the virus in the body and strengthen the immune system. One problem is that the HI virus is capable of modification and can develop resistance to certain drugs. It is then up to the doctor to develop appropriate treatment strategies.
	Specific treatment of the diseases occurring as a result of the infection.
	Immunization of infected persons against various diseases, for example against influenza, pneumonia or hepatitis.
	Symptomatic treatment of the concomitant symptoms of the disease (nausea and lack of appetite).