Why are water treatment facilities spreading super bugs even after the water has been treated?
Is chlorine an effective water disinfectant?
Experts are beginning to ponder these questions as water treatment plants are routinely found to be ineffective. New lab results show that specific infectious superbugs can now spread drug-resistant genes at water treatment plants.
Is it time to curtail the use of antibiotics? They are becoming worthless in the face of evolving superbugs. What natural antimicrobial substances could hospitals and doctors begin using to help patients fight infections without creating and spreading new superbug genes?
What ways can water filtration be improved?
These are the tough questions being asked on the cusp of new findings from Pedro J. J. Alvarez and researchers from Rice University.
Superbug genes can spread to other species of bacteria
In the past decade, Alvarez and his colleagues have isolated abundant antibiotic-resistant genes in China's Hai River. Their mission from there was to find out how these highly evolved genes found their way into the environment in the first place and why they were spreading. They started by inspecting the source - water treatment plants in the area. Since antibiotic-resistant genes are common in fecal bacteria, they studied cultivated bacteria from incoming sewage at nearby water treatment facilities.
Joined by researcher Daqing Mao from Tianjin University, Alvarez extracted bacterial DNA from various water treatment stages at two nearby water treatment plants in China. They also inspected treated sludge, which is typically used by farmers as a fertilizer for their fields.
Using a process called polymerase chain reaction, the researchers isolated and measured various levels of antibiotic-resistant gene NDM-1. This gene first appeared in 2008 and has since then spread to every continent except Antarctica.
They also measured the amount of gene 16S rRNA, which is carried by all bacteria.
What they found in the treated water
Their tests found that both water treatment facilities were releasing thousands of copies per milliliter of the resistant NDM-1 superbug gene. Treated sludge contained even greater amounts - 10 million copies per gram of dry weight!
One treatment plant was actually expelling more of this infectious DNA into the environment than it was taking in!
After observing this widespread dispersion, the team sought to investigate whether this infectious DNA could be passed onto other bacteria species in the surrounding environment. In the lab, they combined NDM-1-carrying bacteria from treated water with sediments from the Hai River that didn't contain the gene.
After nine days of incubation, the researchers found that the NDM-1 gene could be transferred to river sediment bacteria that did not contain the gene!
The study "sounds a huge alarm," says Jeffrey Duchin, chair of the public health committee of the Infectious Diseases Society of America. The more prevalent these s-lactam resistance genes are in the environment, he says, the more opportunity there is for them to spread to other organisms.
New ways to treat water desperately needed
Duchin continues by pointing out that serious s-lactam-resistant infections are primarily caused by bacteria found in hospitals. Hospital patients are at greatest risk for contracting one of these infections, which are resistant to antibiotics. Duchin warns that, if these NDM-1 genes were to spread to bacteria outside hospitals, conditions like urinary tract infections and diarrhea could not be treated with antibiotics. "It would be a disaster," he says.
It's not all doom and gloom, though. Alvarez and his team are working on alternative disinfection methods for water treatment plants that include ultraviolet radiation and photocatalysts.
Moving away from antibiotics
Hospitals will also have to evolve in the years ahead, ditching widespread antibiotic use that is becoming a useless treatment method for superbugs. Natural antibacterial substances will be a more fitting solution going forward. For example, new implementation of garlic and oregano compounds could be sought after in the medical and food industries in the years ahead. Collodial silver and goldenseal root, to name a couple, could be looked to as answers in the future of mainstream antibacterial treatments.
Answers are all around as an awakening to environmental toxins and superbugs is upon us.
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