Poster Abstract Session: Novel Antimicrobial Agents
Friday, October 21, 2011
Room: Poster Hall B1
Background: Phage therapy was first used in France in 1919, and is still used in Eastern and Western Europe. Phage therapy was successfully used in the US in the preantibiotic era, and has an important potential role in the treatment of antibiotic-resistant infections. Phage therapy improved the mortality of Staphylococcus aureus bacteremia in over 500 cases treated in New York 1931-40 by MacNeal. The polyvalent staphylococcal phage of Gratia was produced by the Michigan Department of Public Health in the 1930s, and subsequently in the US as staphage lysate (SPL), still marketed for veterinary use, and used in this study. Commercial phages were produced in France by d'Herelle's Laboratoire du Bacteriophage until 1978, and by the Pasteur Institutes of Paris and Lyon until the early 1990s. The majority of phages produced for specific infections by the Pasteur Institute of Paris from 1959-1960 were for staphylococcal infections resistant to multiple antibiotics. Phage therapy continues to be used in the former Soviet Union, in Poland, and is undergoing a renaissance in Belgium, France, and Australia.
Methods: 14 clinical isolates of S. aureus were obtained from the microbiology laboratory at VA Northern California. The sequenced USA 300 MRSA strain BAA-1556 was obtained from ATCC. Therapeutic preparations of Pyophage used in the Republic of Georgia were obtained from Eliava Institute (Zemphira Alavidze), and from Biochimpharm. The polyvalent bacteriophage of Gratia is manufactured in the United States for veterinary use as Staphage Lysate (SPL) by Delmont Labs.
Results: The MRSA strain BAA-1556 (USA 300) strain was susceptible to two bacteriophage cocktails from the Republic of Georgia, and to staphage lysate (SPL). Three of four MRSA isolates were susceptible to all three phage preparations. Six of ten MSSA isolates were susceptible to all three phage preparations. Each strain was tested several times.
Conclusion: The epidemic USA 300 MRSA strain is susceptible to two commercial bacteriophage preparations from the Republic of Georgia, and to SPL produced in the US. Current studies support the use of phage therapy as practiced in France and Georgia, and in the preantibiotic era in the US. Additional research is needed in an age of increasing antibiotic resistance.
Subject Category: A. Antimicrobial agents and Resistance