Background:  Many HIV-related co-infections cause increases in plasma levels of HIV RNA, but several agents have been reported to cause transient decreases. During the ongoing measles epidemic in Uganda, we evaluated HIV viral dynamics in the Children with HIV and Malaria Project (CHAMP), an observational cohort of 300 HIV-infected children between 1 and 10 years of age. 

Methods:  We identified all children in the cohort who met the WHO clinical case definition of measles between June and September 2006. HIV plasma RNA viral load, absolute lymphocyte count, absolute CD4 count, and CD4 percentage and were evaluated before, on the day of diagnosis, and after clinical measles resolution. The log of plasma viral load and other parameters were compared using a paired 2-tailed Student’s t-test.

Results:  Results are shown in the table for the 9 children who met the measles case definition; 6 were ART-naïve. HIV plasma viral load declined significantly (p <0.0001) during clinical measles by a median of 1.4 log in the ART-naïve children. Absolute CD4 count (p = 0.06) and absolute lymphocyte count (p = 0.04) also declined, but CD4 percentage remained stable (p = 0.46). Notably, the plasma viral load of subject 5 dropped 1.4 log despite a rise in absolute lymphocyte count and absolute CD4 count.  Similar changes were observed in the children on ART, although recent commencement of therapy in subject 9 limits interpretation. Post-measles assessments are available in 2 children to date. HIV plasma viral load of subject 2 returned to 49,227 copies/mL 46 days after diagnosis; plasma viral load of subject 4 was 248,646 copies/mL at 28 days. 

Conclusions:  Acute measles is associated with significant and transient reductions in HIV RNA plasma levels. These data argue against target cell depletion as the exclusive explanation, suggesting instead direct viral and cytokine-mediated interference with replication as potential mechanisms.

* 9 to 75 days prior; # day of measles diagnosis