Vancomycin-resistant Staphylococcus aureus infection

VRSA is defined as a clinical infection caused by Staphylococcus aureus strains that exhibit resistance to vancomycin, typically mediated by the acquisition of the *vanA* gene cluster from enterococci—most commonly Enterococcus faecalis or E. faecium. This resistance mechanism confers high-level resistance to vancomycin and often co-resistance to other glycopeptides such as teicoplanin. The organism retains susceptibility to certain alternative antimicrobials, including linezolid, daptomycin, and ceftaroline, though treatment efficacy varies depending on the specific strain and site of infection.

Clinical manifestations of VRSA infection are consistent with those of invasive S. aureus disease—including skin and soft tissue infections, bacteremia, endocarditis, and osteoarticular involvement—but are complicated by the lack of reliable response to standard glycopeptide therapy. Reported cases have shown variable severity, ranging from mild localized infections to life-threatening sepsis; however, no systematic data on mortality or long-term sequelae are available from the source material. Complications may include persistent bacteremia, metastatic abscess formation, and failure to respond to conventional MRSA regimens.

The global epidemiology of VRSA remains poorly characterized due to its extreme rarity. As of the most recent published review, only a small number of cases have been documented worldwide, primarily in healthcare settings with prolonged exposure to vancomycin and prior colonization with vancomycin-resistant enterococci. No large-scale outbreaks have been reported, and there is no evidence of community transmission in the available sources. Surveillance burden is low, and VRSA is not included in routine national reporting systems outside of select high-risk centers.

Transmission of VRSA is presumed to occur via direct contact with colonized or infected individuals, particularly in healthcare environments where patients are heavily exposed to antibiotics and medical devices. The primary reservoir is likely the human gastrointestinal tract, especially among individuals with prior enterococcal colonization. No environmental persistence data or vector-borne transmission routes are described in the source material.

High-risk groups include patients with prolonged hospital stays, those receiving repeated or long-term vancomycin therapy, individuals with indwelling catheters or surgical implants, and residents of long-term care facilities with known enterococcal colonization. Immunocompromised individuals and those with chronic wounds or diabetes may also be at elevated risk, though this is inferred from general S. aureus pathogenesis rather than directly stated in the source.

Prevention strategies center on infection control measures used for MRSA, including contact precautions, hand hygiene, environmental disinfection, and active surveillance screening in high-risk units. Given the role of enterococcal transfer in VRSA emergence, minimizing unnecessary vancomycin use and preventing cross-colonization with vancomycin-resistant enterococci are key interventions. No vaccines or targeted prophylactic agents are currently available.

In surveillance contexts, VRSA should be flagged when S. aureus isolates demonstrate MIC ≥16 µg/mL to vancomycin, confirmed by standardized methods such as broth microdilution or E-test. Cases require immediate reporting to public health authorities due to their implications for antimicrobial stewardship and outbreak preparedness. Due to the scarcity of cases, confirmation of resistance mechanisms (e.g., *vanA* detection) is recommended for epidemiological tracing and risk assessment.

1. 1 Wikidata. Vancomycin resistant Staphylococcus aureus infections: A review of case updating and clinical features.

ICD-10

ICD-11

Total cases

4

Peak month

2015-05

Coverage

2 reporting countries · 2012-09-14 → 2026-05-09