Multiresistantbacteria continue to spread in Danish hospitals

Previously, the specific group of antibiotic-resistant bacteria known as carbapenemase-producing enterobactereales (CPE) was primarily contracted by Danes who had been hospitalized abroad or stayed outside the country for extended periods. However, in recent years, there has been a spread of these bacteria within Danish hospitals that cannot be traced back to foreign sources.

In 2023, there were altogether 436 reported cases in Denmark, reflecting a 43 percent increase compared to 304 cases the previous year. CPE are typically found in the intestines and are resistant to meropenem or other carbapenems, which are among our most critical antibiotics for treating critically ill patients.

Healthy individuals have a low risk of becoming seriously ill if infected with these bacteria. The greatest risk is for patients who are already weakened or have compromised immune systems due to conditions such as severe cancer. These are patients who have undergone prolonged treatment regimens.

”It is the combination of a particularly vulnerable patient and prolonged antibiotic treatment that can lead to a CPE infection. The bacteria can become dangerous when they leave their usual environment in the intestines and enter the bloodstream, causing sepsis. When our usual antibiotic treatments fail because we were unprepared for the infection being caused by a resistant bacterium, it can become critical with CPE bacteria in the blood.”

Increase in CPE Outbreaks in Hospitals

CPE bacteria are found in both clinical samples from patients and in environmental samples such as from hospital toilets. Environmental samples are taken when multiple cases of CPE bacteria are identified among patients in the same ward. Despite extensive efforts in screening and cleaning in Danish hospitals, there were still more CPE outbreaks in 2023 than in 2022.

”It is concerning that CPE is increasingly found in Danish hospitals. The number of outbreaks with CPE is now at a level where it is becoming a significant issue in the daily operations of some hospital departments, requiring considerable resources to limit its occurrence.”

 In Denmark, there are significant regional differences in the prevalence of CPE bacteria, and extensive research is underway to understand their spread. Many hospital outbreaks cannot be traced back to travel, indicating that CPE now has a domestic reservoir in Denmark.

Many other countries are also facing significant problems with CPE, often to even greater extent. In these countries, CPE bacteria can occur endemically, meaning they are quite common in hospitals, leading to infections with bacteria that are so resistant they cannot be treated with antibiotics. This affects the types of surgeries hospitals are willing to perform, as the risk of subsequent issues with resistant bacteria may become too great.

Fortunately, in Denmark, it remains relatively rare for CPE bacteria to cause sepsis, and they are typically found in swabs, feces, or urine from patients. For instance, the proportion of sepsis cases caused by carbapenemase-producing E. coli remains below 1 percent.

In Denmark, CPE have been systematically surveilled since 2018, and results are published in the annual DANMAP report and presented at the annual DANMAP seminar, both happening in November. The chapter on antimicrobial resistance in human bacteria, which also includes data on CPO findings is already available at DANMAPs website: Chapter 8. Resistance in human pathogens

DANMAP is a joint collaboration between DTU Food Institute and Statens Serum Institut.

Facts

• CPO includes two main groups of bacteria, namely intestinal bacteria and environmental bacteria. The intestinal bacteria constitute the largest group and are referred to as CPE (carbapenemase-producing Enterobactereales). These are well-known intestinal bacteria such as E. coli, Klebsiella pneumoniae, and Citrobacter freundii, which have become so resistant that there are only a few effective antibiotics left for treatment.
• Many individuals infected with CPO bacteria are healthy carriers and have CPO bacteria in their intestines without showing symptoms.
• However, individuals who are already sick and weakened can become seriously ill from CPO bacteria because they are more prone to infections. In this case, CPO bacteria most often cause urinary tract infections or sepsis.
• Transmission occurs primarily through close contact with other people. CPE are intestinal bacteria that are excreted in feces, and the bacteria are particularly found on the skin in the groin area. Environmental bacteria are found on surfaces and in moist environments. You can prevent transmission through good hand hygiene, which is especially important after each toilet visit.

Source: The Danish Health Authority