title: Intermittent low-level viremia in very early primary HIV-1 infection.
abstract: Serial samples from source plasma donors with confirmed new HIV infection were investigated for low-level viremia (LLV) (ie, < 100 genome copies [cp]/mL) at time points preceding the period of steadily rising viremia above 100 cp/mL (ramp-up viremia). Fifteen of 44 plasma donor panels previously studied for the dynamics of HIV viremia during primary infection contained 70 samples with undetectable HIV-1 RNA by quantitative polymerase chain reaction (PCR). On retesting with a sensitive qualitative reverse transcriptase PCR assay (95% detection at 4 cp/mL), we identified LLV in 13 of 15 panels and 23 of 69 retested samples. In 6 panels, a total of 11 samples (1-3 per panel) were consistent with LLV before ramp-up viremia. These samples preceded the first sample with >100 cp/mL HIV by 9 to 25 days (median = 18 days) and were separated from the latter by at least 1 sample with undetectable viremia by the qualitative PCR assay. We conclude that LLV is not uncommon during the very early period of primary HIV infection preceding ramp-up viremia. It is not known if blood is infectious during this period; however, given the low viral concentrations and transient nature of the observed viremic "blips," the risk of infectivity can be assumed to be small.
authors.affiliation: Department of Laboratory Medicine, University of California, San Francisco, San Francisco, CA, USA.
authors.forename: Eberhard W
authors.initials: EW
authors.lastname: Fiebig
authors.forename: Charles M
authors.initials: CM
authors.lastname: Heldebrant
authors.forename: Richard I F
authors.initials: RI
authors.lastname: Smith
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Conrad
authors.forename: Eric L
authors.initials: EL
authors.lastname: Delwart
authors.forename: Michael P
authors.initials: MP
authors.lastname: Busch
mesh_terms: D001782:Blood Donors; D015658:HIV Infections / Q000453:epidemiology*; D015497:HIV-1 / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D015141:Los Angeles / Q000453:epidemiology; D012367:RNA, Viral / Q000097:blood / Q000235:genetics / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019562:Viral Load; D014766:Viremia / Q000453:epidemiology*
chemical_list: D012367:RNA, Viral