The model, a staged progression of HIV is formulated and used to investigate the potential impact of an imperfect vaccine and condom use. The condom is assumed to prevent the transmission of HIV during sexual intercourse if properly used. It is also noted that condoms have their rate of failures. The vaccines on the other hand being also imperfect, has its own characteristics such as protection against infection, causing bypass of primary stage infection , capable of reducing viral load on the infected (especially individuals in the fully blown AIDS infection stage on vaccine could be brought to asymptomatic stage). The model which incorporates individual in the AIDS stage, is rigorously analyzed to give insight into its qualitative features. Using a comparison theorem, the model with mass action incidence is shown to have a locally- asymptotically stable disease free equilibrium whenever a certain threshold, known as the vaccination/condom reproduction number, VC R , is less than unity. The model has a unique endemic equilibrium whenever this threshold exceeds unity. The epidemiological implication of these results are that imperfect vaccine with condom use, can eliminate HIV in a given community if it can reduce the reproduction number to a value less than unity, but the disease will persist if otherwise.
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