title: Efficacy of WHO recommendation for continued breastfeeding and maternal cART for prevention of perinatal and postnatal HIV transmission in Zambia.
abstract: BACKGROUND
  To prevent mother-to-child transmission (MTCT) of HIV in developing countries, new World Health Organization (WHO) guidelines recommend maternal combination antiretroviral therapy (cART) during pregnancy, throughout breastfeeding for 1 year and then cessation of breastfeeding (COB). The efficacy of this approach during the first six months of exclusive breastfeeding has been demonstrated, but the efficacy of this approach beyond six months is not well documented.
  
  
  METHODS
  A prospective observational cohort study of 279 HIV-positive mothers was started on zidovudine/3TC and lopinavir/ritonavir tablets between 14 and 30 weeks gestation and continued indefinitely thereafter. Women were encouraged to exclusively breastfeed for six months, complementary feed for the next six months and then cease breastfeeding between 12 and 13 months. Infants were followed for transmission to 18 months and for survival to 24 months. Text message reminders and stipends for food and transport were utilized to encourage adherence and follow-up.
  
  
  RESULTS
  Total MTCT was 9 of 219 live born infants (4.1%; confidence interval (CI) 2.2-7.6%). All breastfeeding transmissions that could be timed (5/5) occurred after six months of age. All mothers who transmitted after six months had a six-month plasma viral load >1,000 copies/ml (p<0.001). Poor adherence to cART as noted by missed dispensary visits was associated with transmission (p=0.04). Infant mortality was lower after six months of age than during the first six months of life (p=0.02). The cumulative rate of infant HIV infection or death at 18 months was 29/226 (12.8% 95 CI: 7.5-20.8%).
  
  
  CONCLUSIONS
  Maternal cART may limit MTCT of HIV to the UNAIDS target of <5% for eradication of paediatric HIV within the context of a clinical study, but poor adherence to cART and follow-up can limit the benefit. Continued breastfeeding can prevent the rise in infant mortality after six months seen in previous studies, which encouraged early COB.
authors.affiliation: Department of Paediatrics and Child Health, University of Zambia, Lusaka, Zambia; Profngoma09@gmail.com.
authors.forename: Mary S
authors.initials: MS
authors.lastname: Ngoma
authors.affiliation: Department of Pediatrics, Western University, London, Canada.
authors.forename: Amita
authors.initials: A
authors.lastname: Misir
authors.affiliation: Department of Public Health, University of Zambia, Lusaka, Zambia.
authors.forename: Wilbroad
authors.initials: W
authors.lastname: Mutale
authors.affiliation: Department of Epidemiology and Biostatistics, McGill University, Montreal, Canada.|JSS Medical Research, Montreal, Canada.
authors.forename: Emmanuoil
authors.initials: E
authors.lastname: Rampakakis
authors.affiliation: Department of Epidemiology and Biostatistics, McGill University, Montreal, Canada.|JSS Medical Research, Montreal, Canada.
authors.forename: John S
authors.initials: JS
authors.lastname: Sampalis
authors.affiliation: Department of Medicine, University of Toronto, Toronto, Canada.
authors.forename: Angela
authors.initials: A
authors.lastname: Elong
authors.affiliation: Department of Obstetrics and Gynecology, University of Zambia, Lusaka, Zambia.
authors.forename: Sam
authors.initials: S
authors.lastname: Chisele
authors.affiliation: Department of Anesthesiology, University of Zambia, Lusaka, Zambia.
authors.forename: Abel
authors.initials: A
authors.lastname: Mwale
authors.affiliation: Department of Paediatrics, Arthur Davison Children's Hospital, Ndola, Zambia.
authors.forename: Jonathan K
authors.initials: JK
authors.lastname: Mwansa
authors.affiliation: Department of Nursing, Chelstone Clinic, Lusaka, Zambia.
authors.forename: Scholastica
authors.initials: S
authors.lastname: Mumba
authors.affiliation: Department of Paediatrics and Child Health, University of Zambia, Lusaka, Zambia.
authors.forename: Mula
authors.initials: M
authors.lastname: Chandwe
authors.affiliation: Public Health Agency of Canada, Ottawa, Canada.
authors.forename: Richard
authors.initials: R
authors.lastname: Pilon
authors.affiliation: Public Health Agency of Canada, Ottawa, Canada.
authors.forename: Paul
authors.initials: P
authors.lastname: Sandstrom
authors.affiliation: Harvard Medical School, Cambridge, Mass.
authors.forename: Samantha
authors.initials: S
authors.lastname: Wu
authors.affiliation: Grand Challenges, Ottawa, Canada.
authors.forename: Kristen
authors.initials: K
authors.lastname: Yee
authors.affiliation: Department of Medicine, University of Toronto, Toronto, Canada.|Division of Infectious Diseases, Western University, London, Canada; Michael.Silverman@sjhc.london.on.ca.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Silverman
mesh_terms: D019380:Anti-HIV Agents / Q000008:administration & dosage*; D001942:Breast Feeding; D015331:Cohort Studies; D004359:Drug Therapy, Combination; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000517:prevention & control* / Q000635:transmission; D006801:Humans; D007223:Infant; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000188:drug therapy*; D011446:Prospective Studies; D014944:World Health Organization; D015024:Zambia
chemical_list: D019380:Anti-HIV Agents
keywords: breastfeeding transmission of HIV; efficacy of WHO guidelines; infant survival; option B+; perinatal transmission of HIV; vertical transmission