[Simian AIDS virus: review].

The review article on Simian AIDS viruses compiles the presently known facts of AIDS-related simian retroviruses causing immunodeficiencies or lymphomas in nonhuman primates. They are also compared to the situation in man. Simian acquired immunodeficiencies or lymphoproliferative diseases can be caused by infectious (exogenous) oncoviruses (C- or D-type) or by lentiviruses. Infectious D-type oncoviruses of simian origin are: Mason-Pfizer Monkey Virus (MPMV), Simian Retrovirus type 1 (SRV-1), Simian Retrovirus type 2 (SRV-2). The simian D-type oncoviruses do not have a counterpart in man. Infectious C-type oncovirus of monkeys is STLV, related to, but not identical with HTLV. Most serious to man might be simian lentivirus-infections (SIVs) due to the genetic instability of many lentiviruses. The properties of the different viruses, the clinical symptoms and morphological lesions caused by these agents are outlined and the possible dangers to man discussed. MPMV and the SRVs are considered as genetically stabilized and probably not infectious to man, at least no D-type virus infections of man are known. STLV should be treated with caution due to the close genetic relationship of man and nonhuman primates and of STLV and HTLV, although even in STLV-positive colonies no human infections were reported so far. Extreme caution seems advisable regarding the SIVs, not only because of the close phylogenetic and genetic relationships to HIVs. HIVs and SIVs, which are considered to have diverged only comparably recently from common ancestors and from each other possess a marked genetic plasticity (unstability). Therefore working with Old World monkeys, especially of African origin, with tissues of blood obtained from such animals requires certain protective action.