- C J Chantry: Department of Pediatrics, University of California Davis, Sacramento, California, USA. caroline.chantry@ucdmc.ucdavis.edu
BACKGROUND: Transmission of HIV-1 infection through breastfeeding is associated with integrated DNA (provirus) in milk cells. Reduction of HIV-1 DNA in milk may lessen infectivity.
PURPOSE: To investigate efficacy of two methods available in developing countries to reduce HIV-1 proviral DNA in breast milk.
METHODS: Methods simulated field conditions; milk was heated by bringing it to a boil, for instance, over a cooking fire, and lipolysis was done at room temperature. Four HIV-positive pregnant women were recruited for this pilot study, instructed to feed formula exclusively, and to stimulate milk production using pumping. Milk was collected twice weekly for 3 weeks and analyzed qualitatively for HIV-1 proviral DNA by polymerase chain reaction at three stages: 1) fresh, 2) after standing for 6 hours, and 3) after having been brought to the boiling point.
RESULTS: Seventeen samples from 4 mothers were analyzed. Fifteen of 17 fresh samples (88%) had measurable HIV-1 proviral DNA despite all mothers' having had low or undetectable plasma viral loads. Lipolysis (standing at room temperature) for 6 hours did not destroy proviral DNA: 6 of 7 samples (86%) tested positive for DNA after lipolysis. No samples of milk (n = 8) brought to a boil were positive for HIV-1 proviral DNA (p <.0001).
CONCLUSIONS: This preliminary evidence suggests that inherent lipolytic activity of fresh breast milk is inadequate for destruction of HIV-1; bringing breast milk to a boil may result in decreased HIV-1 infectivity; and breast milk cell-associated HIV-1 may not reflect plasma viral load. Nutritional value or possible bacterial contamination of milk treated in this manner was not assessed.