Germ-free children may be more prone to leukaemia

THE long struggle to cure acute lymphoblastic leukaemia (ALL), a childhood blood cancer, is a stand-out tale in the history of medicine. It was a massive endeavour, over decades, with many toxic drugs being tested in different combinations on dying children. It succeeded in the end. Half a century ago, survival rates were less than 0.1%. Today they are about 90%. Yet the cure brings unpleasant side effects, including problems with memory and concentration, and sometimes even other cancers. Globa...