title: Viral load differences in early infection with two HIV-1 subtypes.
abstract: OBJECTIVE
  Information on early HIV-1 infection has come primarily from studies of persons infected with subtype B in North America and Europe; much less is known about other subtypes. The purpose of the present study was to compare the virologic and immunologic parameters following seroconversion among recently-infected persons infected with either of two different HIV-1 subtypes.
  
  
  METHODS
  A prospective cohort study was carried out at methadone treatment clinics administered by the Bangkok Metropolitan Administration, Thailand. A total of 130 HIV-1-infected seroconverters (103 with HIV-1 subtype E and 27 with subtype B) were included in the study. The main outcome measures were serial HIV-1 RNA viral load, natural killer cell percentage, CD4 and CD8 lymphocyte counts since seroconversion.
  
  
  RESULTS
  The demographic and behavioral characteristics of persons with either subtype were similar. Median RNA viral levels at the earliest time within 3 months of seroconversion were more than three times higher for persons infected with subtype E than subtype B (63 100 versus 18 050 copies/ml, P = 0.001). However, this difference decreased over time such that viral loads were similar at 12, 18, and 24 months following seroconversion. The CD4 and CD8 lymphocyte counts were similar in infections with either subtype during the entire period up to 24 months post-seroconversion.
  
  
  CONCLUSIONS
  Higher viral loads associated with subtype E may result from inter-subtype biological differences; however, the epidemiological dynamics of transmission in Bangkok may have also contributed to this phenomenon.
authors.affiliation: Division of HIV/AIDS Prevention--Surveillance and Epidemiology, National Center for HIV, STD, and TB Prevention, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia 30333, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Hu
authors.forename: S
authors.initials: S
authors.lastname: Vanichseni
authors.forename: T D
authors.initials: TD
authors.lastname: Mastro
authors.forename: S
authors.initials: S
authors.lastname: Raktham
authors.forename: N L
authors.initials: NL
authors.lastname: Young
authors.forename: P A
authors.initials: PA
authors.lastname: Mock
authors.forename: S
authors.initials: S
authors.lastname: Subbarao
authors.forename: B S
authors.initials: BS
authors.lastname: Parekh
authors.forename: L
authors.initials: L
authors.lastname: Srisuwanvilai
authors.forename: R
authors.initials: R
authors.lastname: Sutthent
authors.forename: C
authors.initials: C
authors.lastname: Wasi
authors.forename: W
authors.initials: W
authors.lastname: Heneine
authors.forename: K
authors.initials: K
authors.lastname: Choopanya
mesh_terms: D000328:Adult; D018791:CD4 Lymphocyte Count; D018414:CD8-Positive T-Lymphocytes; D005260:Female; D015658:HIV Infections / Q000453:epidemiology / Q000276:immunology* / Q000821:virology*; D006679:HIV Seropositivity; D015497:HIV-1 / Q000145:classification; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012367:RNA, Viral / Q000097:blood; D013785:Thailand / Q000453:epidemiology; D019562:Viral Load
chemical_list: D012367:RNA, Viral