CD4 and infection: According to the rule that the CD4+ T-cell count was reduced by an average of 50/μL per year, the infection time of ≥8 years accounted for 25.2% (180/714), 5–8 years accounted for 23.2% (166/714), 3–5 years accounted for 18.3% (131/714), and <3 years accounted for 33.2% (237/714).