REDUCING THE SPREAD OF HIV-INFECTION IN SUB-SAHARAN AFRICA - SOME DEMOGRAPHIC AND ECONOMIC-IMPLICATIONS

Any reduction in the rate of spread of HIV infection has consequences for the incidence and demographic effects of AIDS. In this paper, output from a published mathematical model of the dynamics of HIV transmission through heterosexual contact is used to study the implications of reducing HIV transmission on demographic patterns and national health budgets in sub-Saharan Africa. The major conclusion is that both the timing and the effectiveness of reducing HIV transmission are non-linearly related to their potential demographic and economic effects. The analysis emphasizes the benefits to be gained from a concerted effort to reduce the spread of HIV infection as early as possible in the time course of the epidemic.; A previously published mathematical model of the transmission of dynamics of HIV is used to simulate the demographic and economic consequences of introducing various degrees of control measures to reduce heterosexual transmission of HIV in sub-Sahara Africa. The model is fully age-structured and its output is projection over time (100 years) of total population size, broken down by age and sex, and numbers with HIV or AIDS. The doubling time of the epidemic is set at 1.5 years; the mean incubation period for AIDS 8 years for adults and 2 years for children; life expectancy of infected persons is set at 1 year; probability of heterosexual transmission 10% per partner contact; that of vertical transmission 50%. The factor beta c, or average rate at which an infected person infects others, varies with level of control introduced. For a population of 16.6 million multiplying at 3.8% per year, with AIDS and no controls, growth rates will begin to decline at year 30, to reach 8.6 million by year 100. Without AIDS, it would have reached 740 million. With AIDS, the structure of the population would change to a higher proportion under 15 and over 25, but lower proportion between 15-25 years. Economically, assuming a GNP of $300 per capita, and an expenditure of $100 per AIDS patient, by year 50 2.4% of the GNP would be spent treating AIDS victims. Figures are also estimated for a fixed or falling GNP, such that funds to spend on AIDS treatment per person would fall over time. If control measures were taken, savings in treatment costs would be substantial, as much as $2.4 billion if transmission were reduced 75% over 25 years. If was noted that sub- Sahara African countries simply do not have funds to pay for Western style treatment of AIDS patients. The cost of the drug zidovudine (AZT) for 1 person is more than that of 1 community health center for a year. Already half the hospital beds are taken up by AIDS patient in some urban areas.