Epidemiological Insights, Mupirocin Resistance, and the Silent Threat of Biofilm Formation

Abstract

ackground

Staphylococcus aureus with methicillin resistance (MRSA) causes life-threatening infections in immune

compromised individuals. Categorization of MRSA as Healthcare-associated (HA-MRSA) and Community

associated (CA-MRSA) has an impact on outcome and treatment protocols. Mupirocin helps in the prevention and

eradication of nasal MRSA; the detection of mupirocin resistance is crucial.

Aims and Objectives

To estimate the prevalence and risk factors associated with CA-MRSA and HA-MRSA.

To assess the prevalence of mupirocin-resistance strains.

To detect biofilm production and its correlation in Healthcare-associated Infection (HCAI)

Methods

Analysed MRSA prevalence in nasal swabs. Categorisation into CA-MRSA and HA-MRSA by risk factor analysis.

Mupirocin resistance as per CLSI guidelines. Biofilm production: 96-well plate method, Tube method, Congo red

agar plate method.

Result

Prevalence of MRSA- 3.37 % (74 out of 2190). Number and Prevalence of CA-MRSA – 10 (13.5 %) and HA-MRSA- 64

(86.5 %). Prevalenceof mupirocin resistance: 1.56% (1 in 64).All strains ofHA-MRSA(100%) werebiofilm producers,

and one CA-MRSA (10%) showed biofilm production. Risk factor analysis showed HA-MRSA in older populations,

prolonged hospitalised patients, ICU admission, indwelling devices, invasive procedures, prior antimicrobial

therapy, prior MRSA carrier, and CA-MRSA in young age, crowded environment, sharing of items, breach in skin

integrity and those who have tattoos.

Conclusion

MRSA and mupirocin resistance are low in our setting, but most MRSA cases are hospital-acquired. Strict Infection

Prevention and Control (IPC) practices are needed to prevent infection spread. Biofilm production in multi-drug

resistant HA-MRSA indicates a link with virulence and healthcare-associated infections (HCAI).