[Transmission of HIV infection]

The increasing number of human immuno-deficiency virus (HIV) infections and the shift from traditional risk groups to the general population give reason for reviewing the routes and risks of virus transmission. In Africa HIV is transmitted mainly by heterosexual contact; in Europe and the USA homosexuality is still the leading cause of infection, however, heterosexual transmission is increasing dramatically. The heterogeneity of HIV strains and host factors may contribute to the progression of HIF infection to AIDS. Vaginal fluid and sperm are infectious, ulcerations caused by venereal diseases and some sexual practices increase the risk of HIV transmission. The use of condoms reduces the risk of infection, but does not eliminate it completely. Saliva is not a likely source for HIV transmission, but oral sex is a risk factor. HIV transmission from mother to child can occur either in utero, during delivery or by infected breast milk. Intravenous drug abusers still get infected by needle sharing. The risk of infection due to therapy with blood products can be minimized by anti-HIV antibody testing, neopterin screening, and virus inactivation. Cell-free blood products can be effectively heated and/or treated with solvent/detergent mixtures. Virus inactivation in fresh frozen plasma is not yet possible.