Outbreak News Today
Infections with bacteria resistant to carbapenems, a group of highly effective antibiotics, pose a significant threat to patients and healthcare systems in all EU/EEA countries, warns ECDC in a Rapid Risk Assessment.
Resistance to carbapenems has been reported with increasing frequency and geographical spread since the beginning of the 1990s. The global rise of carbapenem resistance in a certain family of bacteria called Enterobacteriaceae, or carbapenem-resistant Enterobactericaeae (CRE), represents a threat to healthcare delivery and patient safety.
“We should be very concerned about the rise in carbapenem resistance in the EU/EEA as there are very few options for the treatment of patients with CRE infections” says Dominique Monnet, Head of ECDC’s Antimicrobial Resistance and Healthcare-Associated Infections Programme. “In recent years, the proportions of carbapenem resistance in Klebsiella pneumoniae – a type of Enterobacteriaceae – rapidly increased to high levels in Greece, Italy and Romania. The same could happen to other EU/EEA countries if appropriate measures are not taken. But the spread of CRE can likely be controlled in most countries through the implementation of appropriate prevention and control measures in hospitals and other healthcare settings.”
Two teams of scientists at the annual meeting of the American Society for Microbiology (ASM) are reporting worrisome findings involving multidrug-resistant bacteria in healthcare settings.
In one study, a team led by researchers from Emory Antibiotic Resistance Center reported the first isolation of hypervirulent, multidrug-resistant Klebsiella pneumoniae in the United States. In another, researchers with the Kentucky Department for Public Health and the Centers for Disease Control and Prevention (CDC) found that a small outbreak of carbapenem-resistant infections at a Kentucky hospital in 2017 were caused by different strains and species of bacteria that carried the same drug-resistance plasmids.
Both studies highlight concerns about carbapenem-resistant Enterobacteria (CRE), which cause more than 9,000 healthcare-associated infections each year and have been dubbed “nightmare” bacteria for their resistance to several classes of antibiotics and their ability to spread quickly in healthcare settings. CRE infections, including bloodstream, wound, and urinary tract infections, are exceedingly difficult to treat and have a mortality rate of nearly 50%.
Outbreak News Today
A new study has found that the majority of residents in a rural village of Vietnam harbored multi-drug-resistant (MDR), colistin-resistant E. coli bacteria. Colistin is typically used as a last-resort treatment when there are no other therapy options available. The research is presented at ASM Microbe, the annual meeting of the American Society for Microbiology, held from June 7th to June 11th in Atlanta, GA.
“These results revealed the dissemination of MDR colistin-resistant E. coli, harboring the colistin-resistant mobile gene mcr among commensal bacteria of residents, in a rural community in Vietnam,” said Yoshimasa Yamamoto, Ph.D., Osaka University, Osaka, Japan, presenting author on the study.
The colistin-resistant bacteria were detected in 71.4% of the residents in Nguyen Xa village in Vietnam. All the colistin-resistant isolates were identified as E. coli.
Our environment is contaminated with antibiotics. While this is often at a dilute level, sometimes the concentrations are surprisingly high. There is a growing recognition that this is a public health issue.
Antibiotic resistance accounts for hundreds of thousands of deaths each year and is a major global health threat. While attention has focused on antibiotic overuse, hospital outbreaks and new drug-resistant superbugs, antibiotics in waterways and soils is now viewed as stoking a rise of antibiotic resistance.
How do bacteria become resistant to antibiotics?
Mutation and evolution. Much of the resistance in disease-causing bacteria originate from existing genes. Antibiotics are part of many microorganisms’ natural armoury, so all sorts of resistance genes have always existed. What has changed is that these genes, one by one, jump from harmless bacteria to those that cause disease.
A bacterium may mutate and gain a small advantage in the presence of an antibiotic. And a gene that confers a competitive advantage can spread fast amongst bacteria because of their high rate of replication.
Having locations where bacteria can mingle in a thin soup of antibiotics and resistance genes is a recipe for resistance transferring between different species… and potentially creating new superbugs.
Bacteria that cause infections in humans can develop or acquire resistance to antibiotics commonly used against them1,2. Antimicrobial resistance (in bacteria and other microbes) causes significant morbidity worldwide, and some estimates indicate the attributable mortality could reach up to 10 million by 20502,3,4. Antibiotic resistance in bacteria is believed to develop largely under the selective pressure of antibiotic use; however, other factors may contribute to population level increases in antibiotic resistance1,2. We explored the role of climate (temperature) and additional factors on the distribution of antibiotic resistance across the United States, and here we show that increasing local temperature as well as population density are associated with increasing antibiotic resistance (percent resistant) in common pathogens. We found that an increase in temperature of 10 °C across regions was associated with an increases in antibiotic resistance of 4.2%, 2.2%, and 2.7% for the common pathogens Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus. The associations between temperature and antibiotic resistance in this ecological study are consistent across most classes of antibiotics and pathogens and may be strengthening over time. These findings suggest that current forecasts of the burden of antibiotic resistance could be significant underestimates in the face of a growing population and climate change4.
A new review of research on migrant populations in Europe has found that more than a quarter are infected or colonized with antibiotic-resistant bacteria, with evidence suggesting that the pathogens are being acquired along the migration route or in host countries.
The findings are from a review and meta-analysis of observational studies on antimicrobial resistance (AMR) in migrants conducted by researchers from Imperial College London and published yesterday in the The Lancet Infectious Diseases. The researchers also found that the prevalence of AMR carriage or infection was even higher among refugees and asylum seekers and in high-migrant community settings. But they did not find high rates of AMR transmission from migrants to host populations.
The findings come amid a recent wave of immigration that has brought more than 2 million migrants to Europe since 2015, an influx that’s been driven in part by conflicts and instability in the Middle East and Africa. The authors of the study suggest that the poor conditions that many migrants are exposed to in transit and in host countries—including crowded refugee camps and detention centers with poor sanitation and little access to healthcare—may promote the spread of antibiotic-resistant bacteria. The role of these settings in the spread of infectious diseases has been highlighted in previous studies.
“Poor social conditions in these settings, such as inadequate sanitation, overcrowding, and restricted access to health services (including antibiotics or vaccinations), favour the spread of antibiotic-resistant infections,” the authors write.
A new study by scientists in Sweden indicates that bacteria exposed to small concentrations of antibiotics over time can become highly resistant, a finding the authors say provides an example of how low levels of antibiotics present in many environments may potentially contribute to antibiotic resistance.
In the study, published this week in Nature Communications, researchers from Uppsala University demonstrated that Salmonella exposed repeatedly to an amount of streptomycin that was not strong enough to kill the bacteria or inhibit growth still evolved high-level resistance. The resistance was caused by genetic mutations that haven’t been typically associated with antibiotic resistance and were different from those that develop when the bacteria is exposed to lethal amounts of the drug.
“These results demonstrate how the strength of the selective pressure influences evolutionary trajectories and that even weak selective pressures can cause evolution of high-level resistance,” the authors write.