This gradual decline in viremia in childhood infection coincides with the development of a more effective CD8+ T-cell response with increasing age (88), and it appears that reversion of mutants, such as T242N, in HLA-B*57/58:01-negative children is delayed until the maturing antiviral immune response is sufficiently potent to impose significant traction on the virus (80). The gene discussed is CD8A; the disease is infection.