Received Jun 10; Accepted Dec This is an open access article distributed under the terms of the Creative Commons Attribution License http:
In a study published in the journal mBio, researchers with the University of Exeter Medical School, the University of Hong Kong, and drug-maker AstraZeneca report that even when bacterial communities in wastewater are exposed to small amounts of the antibiotic cefotaxime, selection pressure for clinically important antibiotic-resistant genes occurs.
Moreover, they also found that the selection pressure for resistance may be just as strong as when exposed to high concentrations of the drug. While previous research has shown that resistance can occur when individual species of bacteria are exposed to low concentrations of antibiotics, the impact on complex microbial communities, where different species of bacteria are competing against one another, is less clear.
Even at the lowest concentration of cefotaxime, the abundance of blaCTX-M increased by eightfold over the control sample. In addition, while cefotaxime exposure killed off many species of bacteria in the wastewater samples, it also increased the presence of dangerous gram-negative pathogens such as Pseudomonas aeruginosa and Acinetobacter baumannii.
Co-selection for other resistance to other antibiotics was also observed. Murray and her colleagues theorize that the selection for blaCTX-M at environmentally relevant concentrations of cefotaxime is likely due to clonal expansion of bacteria carrying the gene, along with the horizontal transfer of plasmids carrying the gene.
And the fact that blaCTX-M appeared to outcompete other resistance genes at all concentrations could explain the worldwide spread of CTX-M-type genes, which have become increasingly prevalent in urinary tract infections.
But while the prevalence of the blaCTX-M gene increased over time and with higher amounts of cefotaxime, it ultimately reached a plateau and remained relatively constant until it was exposed to concentrations that were 30 and 50 times the amount used in clinical settings.
The researchers believe this could be the result of the antibiotic-resistant bacteria degrading the cefotaxime and providing protection for susceptible bacteria.
The dangers of antibiotic resistant bacteria led to the White House’s announcement of the National Action Plan for Combating Antibiotic-Resistant Bacteria in March The plan sets a goal of reducing inappropriate antibiotic use in an outpatient setting by 50 percent by Antibiotic resistance is the ability of bacteria to resist the effects of an antibiotic—that is, the bacteria are not killed, and their growth is not stopped. Learn more at CDC’s about antimicrobial resistance webpage. Antibiotic resistance in bacteria is a serious global public health threat. According to the Centers for Disease Control and Prevention (CDC), 2 million people in the U.S. develop antibiotic-resistant infections each year, and at least .
That discovery could have clinical relevance, the researchers suggest, because during antibiotic treatment, antibiotic concentrations can be different in different parts of the body. As a result, even sub-inhibitory levels of antibiotics in some parts of the body, like the gut, could be selecting for resistant bacteria.
Environmental resistance The study adds to a growing concern about the environmental dimension of antibiotic resistance. Several studies in recent years have documented the presence of antibiotics, and antibiotic resistance genes, in agricultural soil, river and lake sediment, tidal estuaries, and wastewater facilities.
Understanding how antibiotics and antibiotic resistance impact the environment, and how to mitigate the effects, is part of the One Health approach to antimicrobial stewardship Antibiotic residues can follow several paths into the environment.
Likewise, antibiotics used in food-producing animals are excreted through manure, which is spread onto fields as fertilizer and can be carried into nearby lakes and streams.
Pharmaceutical production facilities also release antibiotic residues into waterways.When bacteria become resistant, antibiotics cannot fight them, and the bacteria multiply. 3. Some resistant bacteria can be harder to treat side effects or antibiotic resistance. When antibiotics aren’t needed, they won’t.
help you, and the side effects could still hurt. Antibiotic resistance in general has been a problem for as long as antibiotics have existed and is considered an urgent threat to public health; in the fight to slow it .
antibiotic-resistant bacteria. Methods For this systematic review and meta-analysis, we searched PubMed, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and Web of Science for studies published from Jan 1, In five studies of urinary tract bacteria (14 participants), the pooled odds ratio (OR) for resistance was (95% confidence interval to ) within 2 months of antibiotic treatment and ( to ) within 12 months.
The dangers of antibiotic resistant bacteria led to the White House’s announcement of the National Action Plan for Combating Antibiotic-Resistant Bacteria in March The plan sets a goal of reducing inappropriate antibiotic use in an outpatient setting by 50 percent by Antibiotic resistance is one of the biggest threats to global health, food security, and development today.
Antibiotic resistance can affect anyone, of any age, in any country. Antibiotic resistance occurs naturally, but misuse of antibiotics in humans and animals is accelerating the process.