Analysis of the disease course of HIV-1 by entropic chaos degree

When a V3 sequence obtained on the n-th year after infection with human immunodeficiency virus type 1 (HIV-1) was supposed to change into a V3 sequence on the n + 1-th year, the variation between the above two sequences was analyzed by means of entropic chaos degree. The entropic chaos degree measures chaotic aspects of the dynamics causing the variation of sequence. If it is large, then the dynamics produces the large complexity, in other words, the variation of sequences becomes large. As a result, the chaos degree for the dynamics changing the V3 region showed the specific variation patterns throughout from the early stages of infection to death. That is, the variation patterns indicated that the entropic chaos degree is useful to measure the stage of disease progression after HIV-1 infection.