Could a virus be the cure? Phage-hunters search contaminated waters for bacteria-targeting viruses

The river is the heart of the Nyagacho area of Kericho, Kenya, in more ways than one. Flowing through the center of the settlement, it’s a hub of community activity where people gather to bathe, wash clothes and water cattle. The river also receives an inflow of wastewater, leaving sections of the waterway contaminated and teeming with potentially harmful germs.

While most would recognize these polluted water sources as a health hazard and steer clear, infectious disease researchers Martin Georges and Moses “Musa” Gachoya seek them out to try to find helpful bacteriophages that can combat antibiotic-resistant superbugs.

Bacteriophages are viruses that infect only bacteria, generally without harming humans, and they’re estimated to be the most abundant organisms on earth. Unlike antibiotic drugs, which kill a broad spectrum of bacteria, phages attack only certain strains of bacteria. Phages also tend to be highly specific to certain areas because they occur and evolve alongside bacteria affecting certain regions and populations.

Martin and Moses have travelled across Kenya collecting samples from bodies of water, including various rivers throughout the country, the Indian Ocean along the Kenyan coast and crater lakes in the Rift Valley. Another rich source of bacterial phages is sewage treatment plants.

“I think Martin wakes up thinking about where he and Moses can sample from next,” said Dr. Erick Mwengi, a research scientist at the Kenya Medical Research Institute (KEMRI), where Martin and Moses conduct their research. They work out of the Microhub, a KEMRI microbiology laboratory that conducts collaborative infectious disease research with the Walter Reed Army Institute of Research (WRAIR) and other national and international partners.

Once Martin and Moses collect their water samples in the field, they take them back to the lab and separate the components to filter out everything but the phages. They enrich the viruses and encourage them to multiply by giving them “food” — the bacteria that could potentially make humans and animals sick. The phages are then banked for future reference and development as potential treatments.

Their bacteriophage work is conducted in partnership with the WRAIR as part of the institute’s efforts to combat antimicrobial resistance (AMR). As antibiotic use increased through the 20th century, bacteria began to evolve to evade those antibiotics, making them less effective as a treatment or cure for bacterial infections in humans and animals. Because phages target specific bacteria and evolve alongside them, they present a complement or alternative to antibiotics. Some studies have shown they can treat infections that existing antibiotics cannot.

Moses described a recent success when his team identified alternative phage treatments for one patient’s infected burn when a nearby hospital could not find an effective antibiotic. “The patient had been in the ICU for two weeks, and one of the bacterial species found in the wound was resistant to even the hospital’s ‘last resort’ antibiotic. We brought the bacteria back to our lab and found more than 30 bacterial phages from our existing phage bank that could be used against that drug-resistant bacteria.”

Another advantage of phage treatment is that certain variables of traditional drug therapy, like dosage, don’t need to be extensively investigated in clinical trials. A small number of phages multiply in the patient’s gut only up to the point required to overcome the bacterial infection in the body. Once the phages have expelled the infection, they will be cleaned out of the body naturally as waste.

“We are utilizing the war that is going on between bacteria and phages to our advantage, by finding phages and replicating them in our bodies to combat bacterial diseases,” said Martin. “It is a win-win situation for us and the phage. They get their food, and we get back our health.”

This research is conducted by the Walter Reed Army Institute of Research, WRAIR-Africa and the Kenya Medical Research Institute (KEMRI) with funding from the Peer Reviewed Medical Research Program (PRMRP) and Military Infectious Diseases Research Program (MIDRP). The Microhub is supported by HJF/HJFMRI.