title: In utero and intra-partum HIV-1 transmission and acute HIV-1 infection during pregnancy: using the BED capture enzyme-immunoassay as a surrogate marker for acute infection.
abstract: OBJECTIVE
  The BED assay was developed to estimate the proportion of recent HIV infections in a population. We used the BED assay as a proxy for acute infection to quantify the associated risk of mother-to-child-transmission (MTCT) during pregnancy and delivery. Design A total of 3773 HIV-1 sero-positive women were tested within 96 h of delivery using the BED assay, and CD4 cell count measurements were taken. Mothers were classified according to their likelihood of having recently seroconverted.
  
  
  METHODS
  The risk of MTCT in utero and intra-partum was assessed comparing different groups defined by BED and CD4 cell count, adjusting for background factors using multinomial logistic models.
  
  
  RESULTS
  Compared with women with BED ≥ 0.8/CD4 ≥ 350 (typical of HIV-1 chronic patients) there was insufficient evidence to conclude that women presenting with BED < 0.8/CD4 ≥ 350 (typical of recent infections) were more likely to transmit in utero [adjusted odds ratio (aOR) = 1.37, 96% confidence interval (CI) 0.90-2.08, P = 0.14], whereas women with BED < 0.8/CD4 200-349 (possibly recently infected patients) had a 2.57 (95% CI 1.39-4.77, P-value < 0.01) odds of transmitting in utero. Women who had BED < 0.8/CD4 < 200 were most likely to transmit in utero (aOR 3.73, 95% CI 1.27-10.96, P = 0.02). BED and CD4 cell count were not predictive of intra-partum infections.
  
  
  CONCLUSIONS
  These data provide evidence that in utero transmission of HIV might be higher among women who seroconvert during pregnancy.
authors.affiliation: ZVITAMBO Project, Harare, Zimbabwe.
authors.forename: Edmore T
authors.initials: ET
authors.lastname: Marinda
authors.forename: Lawrence H
authors.initials: LH
authors.lastname: Moulton
authors.forename: Jean H
authors.initials: JH
authors.lastname: Humphrey
authors.forename: John W
authors.initials: JW
authors.lastname: Hargrove
authors.forename: Robert
authors.initials: R
authors.lastname: Ntozini
authors.forename: Kuda
authors.initials: K
authors.lastname: Mutasa
authors.forename: Jonathan
authors.initials: J
authors.lastname: Levin
mesh_terms: D000328:Adult; D018791:CD4 Lymphocyte Count; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000453:epidemiology / Q000635:transmission*; D015497:HIV-1; D006801:Humans; D007124:Immunoenzyme Techniques; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D016015:Logistic Models; D008297:Male; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000453:epidemiology*; D014801:Vitamin A; D055815:Young Adult; D015030:Zimbabwe / Q000453:epidemiology
chemical_list: D014801:Vitamin A