Tehran University of Medical Sciences Immunology and Genetics Journal 2645-4831 4 3 2021 09 22 138 154 Amirhossein Rismanbaf Cellular and molecular undergraduate student, Faculty of Modern Sciences, Islamic Azad University of Medical Sciences, Tehran, Iran 2022 07 18 2022 11 01 Antibiotic resistance has been around for years and could lead to a serious crisis in the near future. If the problem of antibiotic resistance is not solved, it is estimated that the increase in antimicrobial resistance would kill 10 million people a year by 2050 (more than the number of cancer deaths) and cost the world economy about 100 trillion USD, which will require immediate development of alternative treatments (1) (2). This problem prompted scientists to find a solution; one of these strategies is the use of bacteriophages as an alternative to antibiotics. In this review article, I will first focus on bacteriophages from various aspects and then, by analyzing the available information, I will try to answer the following questions: • Given the meager standard clinical data and characteristics of bacteriophages, is bacteriophage therapy a safe and reliable method? • Given the short time left before the antibiotic resistance crisis, is it cost-effective to invest in bacteriophage? • Are bacteriophages a double-edged sword? (Besides being used to treat bacterial diseases in the future, do bacteriophages have the potential to become a human virus in the future?) https://igj.tums.ac.ir/index.php/igj/article/view/100 https://igj.tums.ac.ir/index.php/igj/article/download/100/78