A new study by researchers at the University of Washington (UW) sheds some light on this issue. They released important new findings about the effectiveness of widely-used disinfectants against antibiotic-resistant bacteria. Huan He, a UW doctoral student in civil and environmental engineering, was the lead researcher. A team of researchers from University of Florida determined the effects that various disinfectants had on antibiotic resistance genes within bacteria. With his degree in hand, he is currently an assistant professor at Tongji University.
This study’s findings are especially important for healthcare environments, namely hospitals, where the threat of antibiotic resistance continues to be a long-lasting scourge. The study showed nine disinfectants were effective against a variety of antibiotic resistant bacteria. They narrowed their focus to methicillin-resistant Staphylococcus aureus (MRSA), notorious for wreaking havoc in the form of deadly staph infections. The scientists tested what happens to bacterial DNA in different environments. Their aim was to find the best approaches for tackling these persistent pathogens.
Study Overview
The study emphasized the importance of proper disinfection techniques in the fight against antimicrobial resistance. He and his team set up agar plates to test different disinfectants. This enabled them to measure truly effective bacterial inactivation and assess the performance of each disinfectant. The research was published in the journal Environmental Science & Technology. It shows us which disinfectants we have at our disposal to offer the greatest protection against these antibiotic resistant strains.
“Increasingly, environmental engineers are thinking about and treating resistance genes as an emerging contaminant.” – Huan He
Civil and environmental engineering senior faculty member Michael Dodd was the research’s principal investigator. Dodd noted the importance of these findings, which will help direct future disinfection practices. If you’re caring for a patient in a hospital or other health care facility who is infected with an antibiotic-resistant pathogen, do something about it! Now, we have the evidence needed to recommend using specific disinfectants instead of others for cleaning surfaces or instruments the patient potentially came in contact with.
Efficacy of Disinfectants
The research very carefully tested the efficacy of disinfectants under laboratory settings. The researchers stumbled on an unexpected finding. They found that chlorine, the most widely-used disinfectant, didn’t do such a great job against bacterial DNA as they had hoped. Against all hopes and predictions, Phenol proved to be an overwhelming force of power in destroying most kinds of bacteria. This unexpected effectiveness only took place under certain conditions.
“Chlorine, under the conditions we tested, seemed to be less effective against DNA than we originally anticipated, whereas another common cleaner called phenol, which we didn’t think would be effective, actually ended up working relatively well in some cases.” – Michael Dodd
Ultraviolet-UVC irradiation proved to be the most effective approach for disinfecting bacteria and degrading the bacteria’s DNA as well. Dodd emphasized that UV light is a mutagen that acts directly on DNA. As such, they weren’t surprised to find it flourishing in such an environment. It was a welcome result nonetheless. These results indicate UV light can be a powerful tool for healthcare facilities looking to take their sanitation protocols to the next level.
Implications for Healthcare
The relevance of this research goes beyond the lab bench and into the application in practice at healthcare facilities. Antibiotic resistance has become a major global issue. By inching closer to the answers of which disinfectants work best, we will all be doing our part to prevent infections and improve patient outcomes.
Dodd cautioned that not all disinfectants are effective against all bacteria. For instance, benzalkonium chloride is now considered ineffective against resistant strains of bacteria. For one, he urged the use of UV light by health professionals as a tool in their overall disinfection plan.
“For example, UV light could be a good choice, whereas benzalkonium chloride might not be.” – Michael Dodd
This study emphasizes the importance of scientifically targeting bacteria. Beyond that, it prioritizes giving them the fundamental know-how to understand how their DNA functions in various environments. Huan He remarked on the evolving perspective within environmental engineering regarding resistance genes: “What we’re learning is that it’s not just the bacteria that we need to deal with in hospitals and elsewhere. It’s not just how their DNA is acting in these spaces, too.”