Domestic animals contaminate recreational waters and drinking-water sources with excreta and pathogens; but this threat to public health is inadequately understood and is insufficiently addressed in regulations. More than 85% of the world's faecal wastes is from domestic animals such as poultry, cattle, sheep and pigs. These animals harbor zoonotic pathogens that are transported in the environment by water, especially runoff. However little information exists on health effects associated with exposure to this potential hazard to human health; and water standards focused on control of human...