Isolation and chacterisation of Klebsiella phages for phage therapy

Klebsiella is a clinically important pathogen causing a variety of antimicrobial resistant infections, in both community and nosocomial settings, particularly pneumonia, urinary tract infection and septicaemia. We report the successful isolation and characterisation of 30 diverse Klebsiella-infecting phages. The isolated phages are diverse, spanning six different phage families and nine genera. These phages comprise of both lysogenic and lytic lifestyles. Individual Klebsiella phage isolates infected 11 of 18 different Klebsiella capsule types across all six Klebsiella species tested. Our Klebsiella-infecting lytic phages are suitable for phage therapy, based on the criteria that they encode no known toxin or antimicrobial resistance genes. However, none of the characterised phages were able to suppress the growth of Klebsiella for more than 7 hours. This indicates that for successful phage therapy, a mixed cocktail of multiple phages is necessary to treat Klebsiella infections.