title: Effect of in-utero HIV exposure and antiretroviral treatment strategies on measles susceptibility and immunogenicity of measles vaccine.
abstract: BACKGROUND
  The high burden of maternal HIV-infection in sub-Saharan Africa may affect measles control. We evaluated the effect of in-utero HIV-exposure and antiretroviral treatment (ART) strategies on measles antibody kinetics prior and following measles vaccination.
  
  
  METHODS
  Infants aged 6-12 weeks were enrolled. This included HIV-uninfected infants born to HIV-uninfected (HUU) and HIV-infected mothers (HEU). Additionally, we enrolled perinatal HIV-infected infants with CD4% equal or greater than 25% randomized to deferred-ART until clinically or immunologically indicated (Group-3) or immediate-ART initiation (Group-4). Group-4 was further randomized to interrupt ART at 1 year (Group-4a) or 2 years of age (Group-4b). Additionally, a convenience sample of HIV-infected infants with CD4⁺ less than 25% initiated on immediate-ART was enrolled (Group-5). Measles immunoglobulin-G antibodies were quantified by an indirect enzyme immunoassay with titers 330 mIU/ml or more considered 'sero-protective'. The referent group was HUU-children.
  
  
  RESULTS
  The proportion with sero-protective titers at 7.3 weeks of age was higher in HUU (65.2%) compared with any HIV-infected group (range: 16.7-41.8%), but dropped to less than 17% in all groups at age 19.6 weeks. Twenty-eight weeks following the first measles vaccine, Group-4a was less likely to have sero-protective titers (79.3%) as compared to HUU (91.1%; P<0.0001), Group-3 (95.7%; P=0.003) or Group-4b (92.1%; P=0.018). Although the proportion with sero-protective levels were similar between groups immediately postbooster dose, this was lower in HEU (79.6%; P=0.002) and Group-4a (80.3%; P=0.010) compared with HUU (94.3%) 41-weeks later.
  
  
  CONCLUSIONS
  Greater waning of immunity among HIV-infected children in whom ART was interrupted and in HEU following a booster-dose, indicate the possible need for further measles-booster doses after 2 years of age in these children.
authors.affiliation: Department of Science and Technology/National Research Foundation, Vaccine Preventable Diseases, Tygerberg, South Africa.
authors.forename: Omphile E
authors.initials: OE
authors.lastname: Simani
authors.forename: Peter V
authors.initials: PV
authors.lastname: Adrian
authors.forename: Avy
authors.initials: A
authors.lastname: Violari
authors.forename: Locadiah
authors.initials: L
authors.lastname: Kuwanda
authors.forename: Kennedy
authors.initials: K
authors.lastname: Otwombe
authors.forename: Marta C
authors.initials: MC
authors.lastname: Nunes
authors.forename: Mark F
authors.initials: MF
authors.lastname: Cotton
authors.forename: Shabir A
authors.initials: SA
authors.lastname: Madhi
mesh_terms: D019380:Anti-HIV Agents / Q000008:administration & dosage; D000914:Antibodies, Viral / Q000097:blood*; D002675:Child, Preschool; D004359:Drug Therapy, Combination; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000276:immunology* / Q000635:transmission; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007223:Infant; D018445:Infectious Disease Transmission, Vertical; D008297:Male; D008457:Measles / Q000517:prevention & control; D008458:Measles Vaccine / Q000008:administration & dosage / Q000276:immunology*
chemical_list: D019380:Anti-HIV Agents; D000914:Antibodies, Viral; D007074:Immunoglobulin G; D008458:Measles Vaccine