Controversy gained momentum in 2001 and 2002, after Wakefield published papers suggesting that the immunisation programme was not safe. These were a review paper with no new evidence, published in a minor journal, and two papers on laboratory work that he said showed that measles virus had been found in tissue samples taken from children who had autism and bowel problems. There was wide media coverage including distressing anecdotal evidence from parents, and political coverage attacking the health service and government peaked with unmet demands that Prime minister Tony Blair reveal whether his infant son, Leo, had been given the vaccine.