Staged Markov Models Based on CD4+ T-Lymphocytes for the NaturalHistory of HIV Infection

摘要

The natural history of HIV infection has been viewed as a staged processsince the early years of the epidemic. The Walter Reed staging system wasdevised in 1986 (Redfield et al. 1986), and a number of other staging systemshave been used since then. A staged Markov model is a natural mathematicaldevice for modeling such a process. The Markov model has been used in fivebasic areas of HIV/AIDS research: 1.To describe the natural history of HIV infection (Longini et al. 1989a,b,Longini 1990, Longini et al. 1991); 2.to evaluate the effect of covariates on stage-specific progression rates, suchas therapy (Longini et al. 1993); 3.to predict the stage-specific course of the HIV epidemic in selected popula-tions (Longini et al. 1992) and in the USA as a whole (CDC 1992, Brookmeyer1991); 4.to estimate HIV incidence from infection surveys (Satten and Longini1994); 5.to provide estimates for HIV transmission models used to estimate trans-mission probabilities (Longini et al. 1989b) and to investigate the dynamicsof the HIV epidemic (Hethcote et al. 1991a,b, Jacquez et al. 1988, Koopmanet al. 1991).