title: Late postnatal transmission of HIV-1 and associated factors.
abstract: BACKGROUND
  The present study was undertaken to determine the risk and timing of late postnatal transmission (LPT) of human immunodeficiency virus type 1 (HIV-1).
  
  
  METHODS
  Breast-fed infants previously enrolled in 2 trials of antiretroviral prophylaxis were monitored in Malawi. Kaplan-Meier and proportional hazard models assessed cumulative incidence and association of factors with LPT.
  
  
  RESULTS
  Overall, 98 infants were HIV infected, and 1158 were uninfected. The cumulative risk of LPT at age 24 months was 9.68% (95% confidence interval, 7.80%-11.56%). The interval hazards at 1.5-6, 6-12, 12-18, and 18-24 months were 1.22%, 4.05%, 3.48%, and 1.27%, respectively.
  
  
  CONCLUSIONS
  The risk of LPT beyond 6 months is substantial. Weaning at 6 months could prevent >85% of LPT.
authors.affiliation: Department of Epidemiology, Bloomberg School of Public Health, Baltimore, MD 21205, USA. ttaha@jhsph.edu
authors.forename: Taha E
authors.initials: TE
authors.lastname: Taha
authors.forename: Donald R
authors.initials: DR
authors.lastname: Hoover
authors.forename: Newton I
authors.initials: NI
authors.lastname: Kumwenda
authors.forename: Susan A
authors.initials: SA
authors.lastname: Fiscus
authors.forename: George
authors.initials: G
authors.lastname: Kafulafula
authors.forename: Chiwawa
authors.initials: C
authors.lastname: Nkhoma
authors.forename: Shu
authors.initials: S
authors.lastname: Chen
authors.forename: Estelle
authors.initials: E
authors.lastname: Piwowar
authors.forename: Robin L
authors.initials: RL
authors.lastname: Broadhead
authors.forename: J Brooks
authors.initials: JB
authors.lastname: Jackson
authors.forename: Paolo G
authors.initials: PG
authors.lastname: Miotti
mesh_terms: D001942:Breast Feeding; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000453:epidemiology / Q000635:transmission*; D015497:HIV-1 / Q000302:isolation & purification; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D008295:Malawi; D008895:Milk, Human / Q000821:virology; D019829:Nevirapine / Q000627:therapeutic use; D012367:RNA, Viral / Q000032:analysis; D012307:Risk Factors; D013997:Time Factors; D015215:Zidovudine / Q000627:therapeutic use
chemical_list: D012367:RNA, Viral; D015215:Zidovudine; D019829:Nevirapine