Objectives:

This study was undertaken to determine the relative effect of malaria infection on HIV concentration in blood plasma, and prospectively to monitor viral concentrations after antimalarial therapy.

Design:

A prospective, double cohort study was designed to compare the blood HIV-1 RNA concentrations of HIV-positive individuals with and without acute malaria illness. Subjects were followed for 4 weeks after successful malaria therapy, or for 4 weeks from enrollment (controls).

Methods:

Malawian adults with symptomatic Plasmodium falciparum parasitemia (malaria group) and asymptomatic, aparasitemic blood donors (control group) were tested for HIV-1 antibodies to identify appropriate study groups. The malaria group received antimalarial chemotherapy only and were followed with sequential blood films. In both groups, blood plasma HIV-1 RNA viral concentrations were determined at enrollment and again at 1, 2 and 4 weeks.

Results:

Forty-seven malaria patients and 42 blood donors were enrolled. At enrollment blood plasma HIV-1 RNA concentrations were approximately sevenfold higher in patients with malaria than in blood donors (medians 15.1× 10 4 and 2.24× 10 4 copies/ml, respectively, P= 0.0001). No significant changes in median HIV-1 concentrations occurred in the 21 blood donors followed to week 4 (P= 0.68). In the 27 subjects successfully treated for malaria who were followed to week 4, a reduction in plasma HIV-1 RNA was observed from a median of 19.1× 10 4 RNA copies/ml at enrollment, to 12.0× 10 4 copies/ml at week 4,(P= 0.02). Plasma HIV-1 concentrations remained higher in malaria patients than controls (median 12.0× 10 4 compared with 4.17× 10 4 copies/ml, P= 0.086).

Conclusions:

HIV-1 blood viral burden is higher in patients with P. falciparum malaria than in controls and this viral burden can, in some patients, be partly reduced with antimalarial therapy.