COMPARATIVE RATES OF DISEASE PROGRESSION AMONG PERSONS INFECTED WITH THE SAME OR DIFFERENT HIV-1 STRAINS

Rates of HIV-1 progression vary widely. To investigate the relative ef fects of viral and host characteristics on course, we compared persons infected by the same and different subtype B strains. Forty-three inf ection chain clusters were identified, each defined by an infected blo od donor, that donor's recipients, and the recipients' sexual partners , representing second and third generations of infection. Analysis of levels and rates of change in CD4 lymphocyte counts and viral load sho wed that members within a cluster were no more alike in their rates of change in CD4(+) lymphocyte counts or viral RNA levers than among clu sters. Differences in entry viral RNA levels by cluster were marginal and markedly smaller than interindividual differences. These results a rgue that, in general, host factors outweigh differences in viral stra in in determining HIV-1 disease progression.