A MODEL FOR AIDS PATHOGENESIS

The idea is put forward and analysed numerically, that within an infec ted person HIV evolves to increase its reproductivity within the popul ation of CD4(+) cells. A mathematical model predicts initial viremia a nd CD4(+) cell drop after HIV infection and thereafter a slow progress ive decline in the number of CD4(+) cells, although for an extended pe riod HIV is kept at a relatively low level by an active immune respons e. The time span T until the number of CD4(+) cells falls below 20 per cent of its normal value depends on several model parameters. Assumin g Gaussian distributions for these parameters, the model predicts a di stribution function for T which resembles the observed distribution fu nction for the incubation period to AIDS.