There is growing concern about the threat of antibiotic resistant microbes and their impact on our health and health care system. Antibiotic resistant infections kill around 23,000 people per year in the US and cost the health care system about $2 billion per year. Over use of antibiotics in the food industry and in consumer products (soaps, hand sanitizer, cleaners) is likely to blame for a large proportion of the rise in antibiotic resistance microbes, as is environmental pollution from antibiotic waste and residual antibiotics in our waste water. It is interesting to note that waste water treatment plants are considered a hotspot for antibiotic resistance, in part due to residual levels of antibiotics from our household cleaners. It is also possible that fecal contamination in the environment may be contributing to antibiotic resistance, but we lack clear evidence of this association. This is where recent research from a team in Sweden hopes to help.
The team of researchers measured the level of a type of virus called a bacteriophage, specifically the crAssphage. This virus infects bacteria and is specifically in high abundance in human feces and therefore can be used as a marker of human feces contamination in water. The team measured the level of these crAssphage’s in various water samples from around the world and correlated it with the level of antibiotic resistant bacteria in the water. They found a strong and significant correlation between the number of antibiotic resistant bacteria in a water sample and the level of this virus in samples from India, Spain, Singapore, UK, and USA. They also found a strong correlation between the virus and bacterial resistance in waste water treatment plants in Sweden and the US.
This data suggests that contamination of our water with human feces could be contributing to the rise in antibiotic resistance in conjunction with the over use of antibiotics. As such, it should be considered as part of the problem when we are trying to curb the rise in antibiotic resistance. Since this data is primarily correlation in nature, we still don’t know whether the level of human feces and bacteriophage are contributing to the rise in antibiotic resistance of if these bacteriophages are present in higher abundance in feces of people with antibiotic resistant bacteria. More work is necessary to understand the direction of this association. It is important for us to understand all the contributing factors to antibiotic resistance in order to properly get the problem under control. Antibiotics are a fantastic medicine when we use them properly but they won’t be useful for much longer if we don’t deal with this threat.