Bacterial viruses were first reported in 1915 by Fredrick William Twort when he described a transmissible “glassy transformation” of micrococcus cultures that resulted in dissolution of the bacteria (Twort, 1915). Subsequently, Felix Hubert d’Herelle reported a microscopic organism that was capable of lysing Shigella cultures on plates that resulted in clear spaces in the bacterial lawn that he termed “plaques” (d’Herelle, 1917). The term “bacteriophage” was introduced by d’Herelle (1917) as he attributed the replicate nature of this phenomenon to bacterial viruses. During 1919 d’Herelle utilized phages isolated from poultry feces as a therapy to treat chicken typhus and further utilized this approach to successfully treat dysentery among humans (Summers, 2001). Prior to the discovery and widespread use of antibiotics, bacterial infections were treated by administering bacteriophages and were marketed by L’Oreal in France (Bruynoghe & Maisin, 1921). Although Eli Lilly Co. sold phage products for human use up until the 1940’s, early clinical studies with bacteriophages were not extensively undertaken in the United States and Western Europe after the 1930’s and ‘40’s. Bacteriophages were and continue to be sold in the Russian Federation and Eastern Europe as treatments for bacterial infections (Sulakvelidze et al., 2001).