Characterization of active bacteriophages against environmentally isolated S. aureus and study of their efficacy against antibiotic-resistant isolates

Author: Davit Lazviashvili
Keywords: S. aureus; bacteriophages
Annotation:

The number of diseases caused by antibiotic-resistant forms of S. aureus has increased significantly in recent years. The fight against bacterial infections is further complicated by the emergence and spread of antibiotic-resistant strains worldwide. Studies show that 4.95 million people worldwide died in 2019 due to antibiotic-resistant bacteria, making this problem the third most common cause of death. According to these data, scientists estimate that by 2050, up to 10 million people will die each year due to antibiotic resistance. In view of all the above, the search for new alternative therapies is urgent and necessary. Bacterial viruses or bacteriophages are considered to be the most harmless, optimal and effective alternative way against microbial infections. Compared to antibiotic therapy, phage therapy has many advantages, phage therapy is effective against antibiotic-resistant bacterial strains and does not damage the normal microflora of the body. The aim of our study was to characterize bacteriophages active against S. aureus and to study their efficacy against antibiotic-resistant isolates. To achieve this goal, the following tasks were performed: 1) S. aureus strains based on the Research and Development Department of the G. Eliava Institute were identified and their spectrum of antibiotic sensitivity was determined; 2) The spectrum of phage susceptibility of antibiotic-resistant strains to bacteriophages isolated from the environment was determined; 3) Phage with the best therapeutic potential was characterized. Out of 49 bacterial strains, 4 (8.1%) were resistant to Gentamicin, 15 (30.6%) were resistant to Erythromycin, 38 (77.5%) to Ampicillin, 4 to Lincomycin (8.1%), 2 to Clindamycin (4.08%), none to Linezolid was not resistant (0%), 4 (8.1%) to Cephalexin, 13 (26.5%) to Tobramycin, 4 (8.1%) to Oxacillin and 7 (14.2%) to Tetracycline. Phage with the widest spectrum on S. aureus stains has been identified, which was effective on 12 bacterial isolates from 49, only one of them was sensitive to all antibiotics used in our study. We characterized the biology of the selected phage.

Lecture files:

გარემოდან გამოყოფილი S. aureus-ის მიმართ აქტიური ბაქტერიოფაგების დახასიათება და ანტიბიოტიკორეზისტენტული იზოლატების მიმართ მათი ეფექტურობის შესწავლა [ka]