Modelling the epidemiological and economic impact of HIV/AIDS with particular reference to Zimbabwe

HIV/AIDS is a major concern in Zimbabwe, not just in terms of disease spread but also in terms of its impact on society and economic development. The paper presents the epidemiological and economic impact of HIV/AIDS which is analysed using a conventional epidemiological model which captures the dynamics of the epidemic with multi-intervention strategies and a total cost function which analyzes the fiscal economic impact of the pandemic to Zimbabwe. The model assesses the effects of treating using anti-retroviral (ARVs) drugs (based on efficacy and adherence), condom use (based on efficacy and compliance), voluntary testing and counselling and the epidemiological impact on the country. The model shows that reduction in effective sexual contacts by increasing condom use and avoidance of multiple sexual partners has a significant impact in reducing the transmission of the disease. It is shown that without behavioral change, effective treatment of the infected individuals re! suits in more spread of the epidemic. Increasing the incubation by treatment tends to benefit the infected individuals as this increases the number of years lived but the total annual cost maybe too high to be sustained by the government. On the other hand the cost of doing "nothing" as represented by an incubation period of less than 9 years appears to be costly as well. Treatment and caring for those who have developed clinical AIDS constitute a major part of our cost function followed by treatment of those who are infected but have not yet developed clinical AIDS. In Zimbabwe, where the pandemic has reached epidemic proportions, combating the disease and its economic effects successfully will require a large and determined fiscal effort. This study therefore sheds light on the economic consequences of decisions taken in the prevention, treatment and care of HIV/AIDS individuals.