Measurements of human herpesvirus 8 viral load in blood before and after leukoreduction filtration.

BACKGROUND

Human herpesvirus 8 (HHV-8) is likely transmitted through blood transfusion in high-prevalence areas. The efficacy of leukoreduction filtration for reducing HHV-8 in blood has not been reported.

STUDY DESIGN AND

METHODS

Blood was drawn from 45 human immunodeficiency virus-positive men either with Kaposi's sarcoma (KS; n=21) or without KS (n=24) and subject to leukoreduction filtration. HHV-8 viral load was measured in plasma and in blood before and after filtration.

RESULTS

Twelve subjects, all with KS, had detectable HHV-8 viremia before filtration with viral loads of 10(2) to 10(5) copies/mL (mean, 3 × 10(4) copies/mL). After filtration, seven of 12 subjects no longer had detectable HHV-8 in their blood, and five of 12 subjects had detectable HHV-8 that was 90% reduced on average from prefiltration levels. The presence of HHV-8 in the blood after filtration was strongly associated with prefiltration viral loads greater than 1000 copies/mL and the presence of cell-free virus in plasma. None of the subjects without KS had detectable levels of HHV-8 virus in blood before or after filtration.

CONCLUSION

Cell-associated HHV-8 appeared to be effectively removed by leukoreduction filtration. Cell-free HHV-8 was present in 42% of subjects as 1% to 20% of the total virus which was not removed by filtration.