Management of MRSA-Positive Nasal Colonization
For asymptomatic MRSA nasal colonization alone, routine decolonization is NOT recommended unless specific high-risk circumstances exist: recurrent skin infections despite hygiene measures, ongoing household transmission, or pre-operative screening before certain surgical procedures. 1
When to Consider Decolonization
Decolonization should be reserved for specific clinical scenarios rather than applied universally to all MRSA carriers 1:
- Recurrent skin and soft tissue infections (SSTI) that persist despite optimizing wound care and hygiene measures 1
- Ongoing transmission among household members or close contacts despite implementing hygiene interventions 1
- Pre-operative patients in high-risk surgical categories (cardiac surgery, orthopedic implants, device placement) where MRSA colonization increases surgical site infection risk 2-fold to 14-fold 1
Decolonization Protocol When Indicated
When decolonization is warranted, use a combined approach rather than nasal treatment alone 1:
- Intranasal mupirocin ointment applied twice daily to anterior nares for 5-10 days 1
- PLUS topical body decolonization with chlorhexidine solution for 5-14 days OR dilute bleach baths 1
- Decolonization must be coupled with ongoing reinforcement of hygiene measures to be effective 1
The evidence shows that mupirocin alone has limited effectiveness when MRSA colonizes multiple body sites beyond the nares, which is why combined topical body decolonization is recommended 2.
Essential Hygiene Measures (Always Recommended)
These interventions should be implemented for ALL MRSA-colonized patients, regardless of whether decolonization is pursued 1:
- Hand hygiene: Regular handwashing with soap and water or alcohol-based hand gel, particularly after touching skin or contaminated items 1
- Wound management: Keep any draining wounds covered with clean, dry bandages 1
- Avoid sharing personal items: Do not reuse or share razors, linens, towels, or other items that contact skin 1
- Environmental cleaning: Focus on high-touch surfaces (counters, doorknobs, bathtubs, toilet seats) using commercially available cleaners according to label instructions 1
Household Contact Management
The approach to household contacts depends on whether they have symptoms 1:
- Symptomatic contacts: Evaluate and treat for active infection; consider decolonization strategies AFTER treating the active infection 1
- Asymptomatic contacts: Nasal and topical body decolonization MAY be considered, particularly when ongoing transmission is occurring despite hygiene measures 1
Important Clinical Caveats
Do not confuse colonization with infection. MRSA-positive nares without clinical infection does not require systemic antibiotics 2, 3. The anterior nares are the most consistent carriage site, and colonization often precedes infection, but most colonized individuals never develop active disease 3.
Decolonization efficacy is limited. Studies show mupirocin reduces recurrent furunculosis by approximately 50%, not 100% 1. The effectiveness of decolonization is difficult to determine because it has virtually always been studied in combination with other control measures 2.
Transmission dynamics matter. The principal mode of MRSA transmission is via transiently contaminated hands of healthcare workers or household contacts, not directly from colonized nares 3. This is why hand hygiene is paramount and why isolation alone without proper hand hygiene practices fails 4.
Pre-Operative Screening Context
For surgical patients, MRSA screening and decolonization protocols are increasingly implemented as part of bundled interventions 1:
- Patients with prior MRSA history, recent hospitalization, recent antibiotic use, or specific comorbidities (immunosuppression, diabetes, dialysis) have higher colonization likelihood 1
- Bundled approaches including decolonization protocols plus appropriate perioperative antibiotics (vancomycin for MRSA carriers) can decrease postoperative gram-positive infections 1
- This represents a specific high-risk scenario where decolonization has demonstrated benefit 1