Conversely, co-infections with other viruses such as cytomegalovirus (CMV) and hepatitis C virus (HCV) [4, 5, 12], or the CD4+ T-cell apoptosis-inducing phenotype of the HIV Env glycoprotein envelope proteins and immune activation [13], all have been reported to decrease the likelihood of CD4+:CD8+ T-cell ratio normalisation. Here, CD4 is linked to coinfection.