One of the many impressive features of modern medical science is that the WOEIGOH (What on earth is going on here?) reaction is quickly activated and often leads to rapid and practical results. The swift identification of new pathogens has been the result several times in recent years, but the latest example concerns the lethal contamination of some batches of heparin (Takashi K Kishimoto and colleagues. New England Journal of Medicine 2008;358:2457–67; see also editorial, …