Isolation of lysogenic staphylophage and its potential use as a treatment of methicillin‐resistant Staphylococcus aureus surgical infections

Background The aim was to develop a new cost‐effective, accessible method for treating multidrug‐resistant bacterial infections in which the possibility for emergence of resistant strains is greatly reduced. Methicillin‐resistant Staphylococcus aureus (MRSA) surgical wound infection was used as a model for these studies. Methods A collection of lysogenic bacteriophage was made by isolating Staphylococcus‐specific bacteriophage (staphylophage) from clinical MRSA samples from England, Bulgaria and Poland. The phage was selected and characterized according to host range, source, morphology and stability. Resistance profiles of the S. aureus isolates (SAIs) for 16 antibiotics, including methicillin, were determined. Results Some 86 per cent of the SAIs were multidrug resistant. When the 152 SAIs were incubated with eight different S. aureus cultivating strains 79 per cent produced at least one phage able to infect at least one of the cultivating strains. 72·4 per cent were able to infect two or more. Conclusion Lysogenic MRSA isolates are a characterizable, widely available source of staphylophage that can be used as an alternative to the traditional environmental sources. A specific pattern for geographical distribution of lysogenic staphylophage has been demonstrated which further facilitates the isolation process. The narrow host range of bacteriophage compared with chemotherapeutic agents ensures a minimal effect on non‐pathogenic bacteria within the patient. This is an ongoing study and these are preliminary results. At the end of the study a method for isolation and development of therapeutic phage will be available for use in the industrial and hospital setting. © 2000 British Journal of Surgery Society Ltd