Drinking Water Microbiology

Every year, on a global basis, billions of cases of illness result from ingestion of microorganisms in drinking water. The majority of these illnesses are caused by fecal contamination, resulting in diarrhea. In places where access to medical care is not readily available, diarrhea can lead to death from dehydration; unfortunately, 1.5 million people, many of whom are children, die annually as a result. There are hundreds of pathogens that may be present in fecal material, making it not feasible to analyze water for all of them. Thus, the microbiological quality of water is monitored using indicator organisms, such as coliform bacteria, enterococci, and/or bacteriophages, which are much simpler and less expensive to detect. The use of indicators, while not perfect, has resulted in a decrease in the incidence of waterborne disease.