dc.description.abstract | Human immunodeficiency virus, (HIV), is transmitted sexually by both homosexual and
heterosexual contact. Heterosexual transmission is the major route of HIV spread in
Africa, accounting for over 70% of all transmissions, and is still the mode of transmission
that is least understood. The development of an animal model for heterosexual
transmission is therefore of great value in understanding this mechanism of transmission
and more importantly, for testing candidate anti-retroviral and immuno-modulating drugs
as well as vaccines. In the attempt to develop the baboon as a heterosexual transmission
animal model for HIV, six adult baboons were inoculated with HIV-2 and two with
SimianlHuman Immunodeficiency Virus, (SHIV). Of the six exposed to HIV-2, two were
inoculated via the penile urethra, two vaginally and two intravenously. Of the two exposed
to SHIV, one was inoculated vaginally and the other intravenously. Two SIV negative
baboons were also inoculated intravenously with saline and served as controls. Blood
samples were obtained for culture and serology from all animals at regular time-points and
biopsies of inguinal lymph node, spleen, liver, bone marrow and cerebral spinal fluid were
obtained for culture from three animals, each representing one group. Virus was recovered
from both blood and inguinal lymph node of all SHIV-infected and one of six HIV-2-
infected baboons. In addition, all animals inoculated with SHIV were antibody positive by
ELISA and one of six HIV-2-infected animals was weakly positive. These results show that
the baboon can be developed further as an animal model for HIV. If developed further, the
baboon will be a valuable and practical animal model for studying heterosexual
transmission, assessing the role of co-factors in heterosexual transmission of HIV and
testing the effectiveness of spermicides, pharmacological agents and vaccines in preventing
the heterosexual transmission of HIV. | en |