ABSTRACT
Today, the growing incidence of bacteria that are resistant to most or all available antibiotics is leading to widespread renewed interest in possibilities of phage therapy. Since 1930s, a major medically important commercial use of phages has been for so-called phage typing, using patterns of sensitivity to a specific battery of phages with particularly narrow host ranges to precisely characterize bacterial strains. The strong understanding of phage biology gained has the potential to facilitate far more rational thinking about the therapeutic process and the selection of therapeutic phages. However, it was clear that the phages readily entered the body from the digestive tract and multiplied internally wherever appropriate bacteria were present, as measured by the level of their occurrence in blood and urine as well as by therapeutic effects. This interesting and rather unexpected finding has been replicated in many studies and systems, while control studies in the absence of bacterial infection seldom show any phage in the urine.
