Drinking Water Quality and the Geospatial Distribution of Notified Gastro-Intestinal Infections

GRILC, Eva; GALE, Ivanka; VERŠIC, Aleš; ŽAGAR, Tina; SOCAN, Maja

People can catch waterborne diseases from contamination of both natural and man-made environments with human and animal feces (7) . Diarrheal disease due to contaminated food and water, as a cause of death, is declining worldwide (8) . Halving a number of people without sustainable access to safe drinking water had an enormous impact on decreasing the incidence of diarrheal diseases (9) . A comprehensive literature review identifies 1415 species of infectious organisms known to be pathogenic to humans, including 217 viruses and prions, 538 bacteria and rickettsia, 307 fungi, 66 protozoa and 287 helminths. Out of these, 868 (61%) are zoonotic, that is, they can be transmitted between humans and animals (10) Hygienic measures, socio-economic changes and climatic changes have a significant impact on the emergence and spread of water-associated microorganisms. The occurrence of some has gradually been reduced, e.g. typhoid fever, while the incidence of others has risen: Campylobacter, E. coli O157:H7, noroviruses, Cryptosporidium and Giardia (12) . Some new pathogens include environmental bacteria and viruses that are highly capable of surviving and proliferating in water distribution systems. Moreover, they are highly resistant to chemical disinfecting procedures (12) . Waterborne viruses are gaining in importance as etiological agents of acute gastroenteritis. In children, they cause mixed viral infections with a severe clinical picture (12) .