Can a bacterial virus from Jerusalem sewage prevent root canal infections?

Every year, drug-resistant infections kill more than 50,000 people across Europe and the United States, and hundreds of thousands more around the world. According to the Review on Antimicrobial Resistance commissioned by the UK Prime Minister, failing to address the growing problem of drug-resistant infections could cause 10 million deaths a year and cost up to $100 trillion USD by 2050.

Now, researchers from the Hebrew University of Jerusalem's Faculty of Dental Medicine propose a way to turn the tables on harmful bacteria that infect humans, by infecting them with tiny viruses called bacteriophages. In a strange twist, one such virus, cultivated from Jerusalem sewage, may help prevent infections following dental procedures.

Just a few decades ago, antibiotics were considered wonder drugs. Ironically, because they worked so well, they were used too often, leading to the rise of drug-resistant bacteria. These untreatable pathogens evolved mutations enabling them to resist the antibiotics that doctors prescribe to fight them.

One such pathogen is Enterococcus faecalis, a bacterium inhabiting the gastrointestinal tracts of humans.

This life-threatening pathogen causes diseases ranging from endocarditis (a potentially fatal heart infection) to bacteremia (harmful bacteria in the bloodstream), as well urinary tract infection, meningitis, and post-treatment root canal infections.

E. faecalis is a highly durable strain, and is especially hard to target when grouped in a sticky bacterial cluster called biofilm. E. faecalis is often recovered from persistent infections associated with root canal treatments, and infection may persist in 20-33% of root canals.

The frustrating rate of infections reflects the limitations of current treatment options. Thus it is essential to develop additional ways to target highly virulent bacteria such as E. faecalis, especially when in biofilm form.

A promising alternative approach to traditional antibiotics is bacteriophage therapy. Bacteriophages, or "phages," are viruses that infect bacteria. Phages play a key role in maintaining the natural balance in their predator-prey relationship with bacteria. They co-evolved with their bacterial hosts to be highly effective specific "professional bacterial killers."

Now, a research team - led by Dr. Ronen Hazan from the Institute of Dental Sciences at the Hebrew University, and Dr. Nurit Beyth from the Hebrew University-Hadassah School Of Dental Medicine, together with their co-workers and students, Dr. Shunit Glaser, Leron Khalifa, Daniel Gelman and Yair Brosh - has identified a way to use phage therapy to target E. faecalis biofilms.

The researchers isolated an anti-E. faecalis phage from sewage effluents retrieved from a Jerusalem sewage treatment facility. The phage, named EFDG1, is capable of infecting the V583 strain of E. faecalis, which is resistant to vancomycin, the most effective anti-E. faecalis antibiotic.