Thursday, December 15, 2016

An antibiotic alternative? Hope through science.

Antibiotic resistance test. Image: Dr. Graham Beards
A toddler suddenly becomes deathly ill. In the ER she is diagnosed with dysentery, caused by a rare but particularly aggressive form of Salmonella. One antibiotic after another fails because the strain, picked up when her family was traveling across parts of Asia, resists multiple antibiotics; but there is an alternative new drug. Like a guided missile, the drug targets only the disease causing Salmonella. Not only that, but as long as Salmonella remains, the drug particles replicate, increasing in number until the infection subsides. Despite the carnage, the toddler’s gut microbiome remains unharmed – no need for probiotics or fear of complications like C. diff.  If Salmonella responds by evolving resistance, the drug may respond in turn engaging an ages old evolutionary dance. By the next morning the color returns to her cheeks. By evening, she is cured.
While still a fantasy here is the U.S., the scenario has been playing out in Eastern European hospitals and clinics for nearly a century. The “new” drug is a virus called a bacteriophage (or simply “phage”), that attacks bacteria. It is a cure nearly as old as life; at least as old as bacteria. Microbiologists have suggested that for every strain of bacteria on earth from the oceans to those populating our own microbiomes– there is at least one, if not multiple bacteriophages.
phage
Viral phages infecting a bacterium. Image: Dr. Graham Beards
As diseases like TB, gonorrhea, E.coli, staph and other common infections increasingly evolve to resist our antibiotics, health care workers are fast becoming desperate for new antimicrobials that are both effective and cause minimal damage to our own microbiomes. Bacteriophages are potent antimicrobials. Once disparaged here in the U.S. and in western medicine in general, these bacteria infecting viruses are making their way back into academic and biotech laboratories. If all goes well, they may be coming to a pharmacy near you.
We now know that throughout our existence viruses have woven in and out of life – leaving their stamp on most if not all living things. By some accounts up to eight percent of our genetic material came to us by way of viruses. Yet for all the fear and harm we associate with viruses many (if not most) are phages, infecting bacteria, like those in our microbiome. Genomics is just beginning to reveal the diversity and representations of these entities in nature and within our bodies. But the role that phages can serve as potent antimicrobials is no mystery. As infectious agents of bacteria they are a normal and pervasive component of earth’s flora, and they have already saved countless lives. One day they just might save us or our loved ones.
This is only one solution. There are plenty of others in the works. Lets just hope they get the funding they need in the coming years.
Adapted from  Natural Defense: enlisting bugs and germs to protect food and health (Island Press, Spring 2017.) 

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