Specifically, for the group with initial CD4 counts between 200 and 350 cells/μl, infection with CRF55_01B was associated with a significantly lower declining rate ([cells/μl]1/2/year) than with CRF01_AE (13.4 [95%CI 8.2–18.6] vs. 22.9 [95%CI 15.8–30.0], P < 0.05), while similar to CRF07_BC (13.4 [95%CI 8.2–18.6] vs. 10.8 [95%CI 8.2–13.4], P = 0.383). Here, CD4 is linked to infection.