title: Temporal reduction of HIV type 1 viral load in breast milk by single-dose nevirapine during prevention of MTCT.
abstract: Short-course zidovudine (ZDV) with or without a single dose of nevirapine (sdNVP) is widely used to prevent mother-to-child HIV transmission (PMTCT). However, more data on viral load in breast milk following pMTCT regimens are needed. In a randomized PMTCT study in Botswana, in which half of the women received sdNVP in labor, stored samples from mothers assigned to breastfeed were analyzed for HIV-1 RNA in breast milk supernatant. A total of 527 samples from 282 women, collected at delivery, 2 weeks, 2 months, and 5 months postpartum were available for testing. Cell-free breast milk HIV-1 RNA was detectable (>40 copies/ml) in 44.8% (236/527) of samples analyzed. Women randomized to sdNVP + ZDV were more likely to have undetectable breast milk viral loads at 2 weeks postpartum compared with those who received ZDV alone (67.8% vs. 38.5%, p = 0.002). By 2 months postpartum the difference between study arms disappeared, and 43.8% of women who received sdNVP + ZDV had undetectable HIV-1 RNA compared to 53.8% of the ZDV alone group (p = 0.19) and 60.5% vs. 64.5%, respectively, at month 5 (p = 0.61.) The addition of sdNVP to antenatal short-course AZT resulted in significantly reduced breast milk viral loads at 2 weeks postpartum suggesting a reduced risk of MTCT during the early postpartum period. However, viral loads in both study arms were comparable at 2 and 5 months postpartum, suggesting that the receipt of sdNVP in labor may defer rather than blunt the postpartum viral load rebound seen in breast milk after the discontinuation of ZDV.
authors.affiliation: Department of Biological Sciences, University of Botswana, Gaborone, Botswana.
authors.forename: Raabya
authors.initials: R
authors.lastname: Rossenkhan
authors.forename: Thumbi
authors.initials: T
authors.lastname: Ndung'u
authors.forename: Teresa K
authors.initials: TK
authors.lastname: Sebunya
authors.forename: Jose E
authors.initials: JE
authors.lastname: Hagan
authors.forename: Roger
authors.initials: R
authors.lastname: Shapiro
authors.forename: Vladimir
authors.initials: V
authors.lastname: Novitsky
authors.forename: Sikhulile M
authors.initials: SM
authors.lastname: Moyo
authors.forename: Ibou
authors.initials: I
authors.lastname: Thior
authors.forename: Shahin
authors.initials: S
authors.lastname: Lockman
authors.forename: Rebecca
authors.initials: R
authors.lastname: Mitchell
authors.forename: Soyeon
authors.initials: S
authors.lastname: Kim
authors.forename: Rosemary
authors.initials: R
authors.lastname: Musonda
authors.forename: Erik
authors.initials: E
authors.lastname: van Widenfelt
authors.forename: Joseph
authors.initials: J
authors.lastname: Makhema
authors.forename: M
authors.initials: M
authors.lastname: Essex
mesh_terms: D019380:Anti-HIV Agents / Q000008:administration & dosage*; D001942:Breast Feeding / Q000009:adverse effects; D005260:Female; D015658:HIV Infections / Q000517:prevention & control* / Q000635:transmission / Q000821:virology; D015497:HIV-1 / Q000187:drug effects*; D006801:Humans; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D008895:Milk, Human / Q000821:virology*; D019829:Nevirapine / Q000008:administration & dosage*; D049590:Postpartum Period / Q000187:drug effects*; D019562:Viral Load / Q000187:drug effects*; D015215:Zidovudine / Q000627:therapeutic use
chemical_list: D019380:Anti-HIV Agents; D015215:Zidovudine; D019829:Nevirapine