Bacteriophages as indicators of pollution

Water pollution is an undesired reality encountered in many countries. To prevent major outbreaks of infectious disease caused by pathogenic microorganisms such as viruses, bacteria, and protozoa that contaminate the water, the scientific community has searched for various indicators that could be used to alert their presence. Among the possible indicators, bacteriophages are receiving increasing attention because of the concern with waterborne viral diseases. This review summarizes the advantages and disadvantages of utilizing bacteriophages as pollution indicators as seen from the somewhat confusing information accumulated from almost 50 years of research and proposes some new directions in the application of bacteriophages as indicators. Bacteriophages have been studied worldwide as pollution indicators because of the ease of their detection and their morphological similarity to human viruses. In addition, detection of human viruses is still a highly skilled and costly process. Generally speaking, bacteriophages have shown good potential application as indicators in certain situations, but some additional effort is needed in order to determine their real merit.