Phages against infectious diseases

(Bacterio)phages (viruses that infect bacteria) are the most abundant entities on earth. Phages are the natural predators of bacteria and therefore have a great antibacterial potential. Immediately after their discovery, in the early twentieth century and before the antibiotic era, they were extensively used to treat infectious diseases. Now, on account of the spread of antibiotic resistance, the interest in phage therapy has been reborn and the recent advances on phage biology and host interactions have reinforced their therapeutic potential. This chapter describes the most important features of phages that make them valuable alternatives to antibiotics in controlling infectious diseases and the challenges that phage therapy is facing for them to be brought into clinical practice.