Alicia- The speaker did not clarify exactly what she meant by a detergent step. She was concerned that heat treatment alone (at a level low enough to avoid denaturing all the proteins in the milk as well as the virus) would not be 100% effective. She felt that the cell membrane of the virus--which is essentially the same as that of the T-lymphocyte the virus had infected--needed to be disrupted to be completely sure that the milk would not be infectious. She did not have any data at hand to support this, however. She did have an extensive reference list for her talk. I'll let you know if I find any more info in any of the articles I pull. I'd be interested if anyone else has any info about the effectiveness of pastuerization. -- Anne Montgomery, M.D. [log in to unmask] St.Peter Hospital Family Practice Residency Olympia, WA