A stochastic model for medium-term estimation of the prevalence of HIV infection in a South African heterosexual population.
This paper describes the development of a micro-simulation model to estimate the extent of HIV infection among black heterosexual South Africans and attempts to predict the number of newly acquired cases of HIV infection for the period 1985-2000. Owing to the lack of key data inputs, many assumptions are made. The inputs used are estimated demographic transition, HIV-positive immigrants, probability of being HIV-positive, probability of acquisition of infection upon at-risk contact by gender, time to AIDS distribution, average number of new sexual partners over time by age and gender, average number of sexual contacts per partner by gender and age group, and probability of sexual contact by age group between genders. Paediatric, homosexual and intravenous HIV cases are excluded from the model. The results indicate a fairly rapid increase in HIV infection from 1988 until the year 2000, when 5,664,487 adults, i.e. approximately 27% of the total adult (15-60 years) black population, could have become HIV-positive. This first phase of the model does not include the effect of a change in behaviour or the possible effect of effective drugs or vaccines and is therefore a worst-case scenario, maximum-potential estimate. The results are very similar to previously published South African actuarial and macro-simulation models.
Groeneveld
H
H
Department of Statistics, University of Pretoria.
Padayachee
N
N
D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology; D005260:Female; D005544:Forecasting / Q000379:methods; D015658:HIV Infections / Q000453:epidemiology*; D006801:Humans; D008297:Male; D015233:Models, Statistical; D015995:Prevalence; D013019:South Africa / Q000453:epidemiology; D013269:Stochastic Processes