Waterborne diseases – What are the primary killers?

This mini-review aims to give an outline of the micro-organisms that are responsible for the most frequent and severe waterborne diseases. Waterborne diseases represent the major threat to global human health and are carried by pathogenic representatives of the three principle groups of organisms; bacteria, viruses and protozoa (the other major group, fungi, do not represent a significant threat). The major carriers of bacterial gastroenteritis are members of the Enterobacteriaceae that include the genera Escherichia, Salmonella, Shigella and Yersinia. In addition, Vibrio cholera remains a potent threat with emergent strains and a different geographic distribution than previously. Rotaviruses present the greatest threat of the viruses with Hepatitis A and E viruses. Waterborne protozoan disease, that can be endemic in many developing countries, is caused predominantly by Cryptosporidium parvum, Entamoeba histolytica and Giardia duodenalis.