Introduction to Phage Therapy
Phage therapy is the use of viruses to treat bacterial infections. Application of bacteriophage to a bacterial infection will result in the phage infecting, replicating, and then destroying their bacterial hosts. The newly synthesized phage can then go on to infect other bacteria, resulting in the rapid removal of the infection. The use of phages to treat bacterial infections has received new attention due to the appearance of strains of previously treatable pathogens such as methicillin-resistant Staphylococcus aureus, and multidrug-resistant tuberculosis. Additionally, the specificity of bacteriophages to a single pathogenic strain will avoid killing "good" bacteria, such as when treating an infection within the digestive system.
The discovery of a bacterial-killing substance that could pass through extremely small filters was observed independently several times:
|Year||Discoverer, country, microbe sensitive to phage|
|1896||Hankin, British, Vibrio cholerae|
|1898||Gamaleya, Russian, Bacillus subtilis|
|1915||Twort, British, Staphylococcus|
|1917||d'Herelle, French-Canadian, Shigella. Coined the term "bacteriophage".|
The first therapeutic usage of phage was in 1919, to treat a child with severe dysentery. In a classic case of old-school science, the lead researchers (which included d'Herelle) drank portions of the bacteriophage preparation the day before treating the child, to check the treatment's safety in humans. The child fully recovered within a few days, and further tests confirmed the result.
In the 1930s and 1940s, bacteriophage preparations were developed and sold by L'Oréal and the Eli Lilly Company. The development and mass production of antibiotics in the late 1940s halted research into phage therapy in the West, due to the superior efficacy and simplicity of antibiotics. Research continued in the Soviet Union. Currently, the only country that has approved phage therapy for human use is Georgia.