[Properties and transmission of the AIDS virus]

The acquired immunodeficiency syndrome (AIDS) is caused by a retrovirus. LAV/HTLV-III is mainly transmitted by blood and sperm. More than 90% of the newly infected persons belong to four risk groups: male homosexuals, drug addicts, persons with multiple changing sex partners, and bisexuals. Infected individuals carry the virus and antiviral antibodies simultaneously in their blood. The antibodies can be demonstrated by the ELISA and immunofluorescence tests, but positive and questionable test results must be confirmed by the immunoblot. Not all of the persons carrying the virus will develop clinical symptoms, but the percentage of those suffering from severe illnesses rises with time and reaches 40% after 8 years. At present, there is no effective therapy and no vaccine will be ready in the near future. Therefore, it is necessary to take all precautions possible to prevent new infections.