Lower human immunodeficiency virus (HIV) type 2 viral load reflects the difference in pathogenicity of HIV-1 and HIV-2.
Human immunodeficiency virus type 2 (HIV-2) is less pathogenic than HIV type 1 (HIV-1), but the mechanisms underlying this difference have not been defined. We developed an internally controlled quantitative reverse transcriptase-polymerase chain reaction to measure HIV-2 viral load and determined levels of plasma virus in a cohort of registered commercial sex workers in Dakar, Senegal. The assay has a lower limit of detection of 100 copies/mL and is linear over 4 logs. HIV-2 viral RNA was detectable in 56% of all samples tested; the median load was 141 copies/mL. Levels of viral RNA in the plasma were inversely related to CD4+ cell counts. HIV-2 and HIV-1 viral loads were compared among the seroincident women in the cohort; the median viral load was 30x lower in the HIV-2-infected women (P<.001, Wilcoxon rank sum test), irrespective of the length of time infected. This suggests that plasma viremia is linked to the differences in the pathogenicity of the 2 viruses.
Popper
S J
SJ
Department of Immunology, Harvard AIDS Institute, Harvard School of Public Health, Boston, Massachusetts, USA.
Sarr
A D
AD
Travers
K U
KU
Guèye-Ndiaye
A
A
Mboup
S
S
Essex
M E
ME
Kanki
P J
PJ
D000328:Adult; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000276:immunology / Q000503:physiopathology* / Q000821:virology; D006679:HIV Seropositivity / Q000276:immunology / Q000503:physiopathology* / Q000821:virology; D015497:HIV-1 / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D015498:HIV-2 / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D006801:Humans; D012367:RNA, Viral / Q000097:blood*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012675:Senegal; D011477:Sex Work; D014158:Transcription, Genetic; D019562:Viral Load
D012367:RNA, Viral