Enterococcus faecium is an opportunistic gram-positive bacterium that normally inhabits the human intestine. It is part of the normal microflora, but under certain circumstances—such as weakened immunity, prolonged antibiotic use, or invasive procedures—it can cause severe illness. Specifically, these are nosocomial infections, which particularly affect hospitalized and intensive care patients.

Over the past decades, Enterococcus faecium has become a serious challenge for the medical community due to the growth of its antibiotic resistance, including resistance to vancomycin, one of the last reserve antibiotics.

How does Enterococcus faecium infection occur and how can it be prevented?

E. faecium is most often transmitted in healthcare settings—through contaminated surfaces, equipment, or contact with infected personnel. The bacteria enter the body through hands, wounds, urinary catheters, or the respiratory tract.

Prevention includes:

• strict hand hygiene;

• disinfection of surfaces;

• use of disposable gloves and isolation measures;

• justified use of antibiotics;

• regular screening of patients at risk.

Diseases caused by E. faecium

Enterococcus faecium causes a wide range of diseases, including:

• bacteremia (presence of bacteria in the blood);

• endocarditis (inflammation of the inner lining of the heart);

• urinary tract infections;

• abdominal infections;

• skin and soft tissue infections.

Symptoms depend on the location of the disease, but common ones include: increased body temperature, abdominal or chest pain, general weakness, and worsening of condition in patients with severe illnesses.

E. faecium and antibiotic resistance

The reasons for the increasing resistance of E. faecium are varied:

• excessive and uncontrolled use of antimicrobial drugs in medicine and agriculture;

• genetic mutations and horizontal gene transfer;

• the ability of bacteria to form biofilms that hinder the penetration of drugs;

• adaptive mechanisms for survival in the hospital environment.

Particularly critical is the spread of vancomycin-resistant enterococci (VRE), which are virtually refractory to standard therapy.

Phages as an alternative to antibiotics

Bacteriophages are viruses that can specifically infect and destroy bacteria.

Advantages of phage therapy:

• specificity of action (does not harm beneficial microflora);

• effectiveness against biofilms;

• non-toxic;

• the ability to evolve with bacteria.

For the fight against Enterococcus faecium, this means the ability to specifically destroy even the most resistant strains.

Phage therapy studies against Enterococcus faecium

In 2024, researchers from the Chinese Academy of Sciences published a paper on the EF-M80 phage, which effectively kills VRE strains, including E. faecium. It demonstrated high stability and efficacy against biofilms.
Source: https://www.frontiersin.org/articles/10.3389/fmicb.2024.1416971/full

In 2023, a case of successful phage therapy in a patient with chronic, recurrent E. faecium infection was described in the journal mBio. The combination of bacteriophages and daptomycin reduced the bacterial load.
Source: https://journals.asm.org/doi/10.1128/mbio.03396-23

The European consortium EVREA-Phage is working to develop phage therapy to prevent infections in transplant patients colonized with vancomycin-resistant E. faecium.
Source: https://www.dzif.de/en/projekt/evrea-phage

Enterococcus faecium is a bacterium that has evolved from a harmless inhabitant of our intestines into one of the most dangerous adversaries in hospitals. Its ability to adapt, form biofilms, and develop antibiotic resistance requires new, innovative treatment approaches.

Bacteriophages , our microscopic allies, are demonstrating powerful potential in the fight against this threat. They have already demonstrated effectiveness in laboratory settings and in selected clinical cases. Further scaling up of research, government support, and the development of phage banks could make phage therapy not an exotic alternative, but a standard of treatment of the future.