433 Prevalence of nasal carriage of MRSA in patients and healthcare workers at Mulago Hospital in Kampala, Uganda

Saturday, March 20, 2010
Grand Hall (Hyatt Regency Atlanta)
Ajay K. Sethi, PhD , University of Wisconsin-Madison, Madison, WI
Shelley Chang, PhD , Case Western Reserve University, Cleveland, OH
Achilles Katamba, MBChB, PhD , Makerere University, Kampala, Uganda
Bruce Kirenga, MBChB, MMED , Mulago Hospital, Kampala, Uganda
Hannington Baluku , Makerere University, Kampala, Uganda
Freddie Bwanga, MBChB, MMed , Makerere University, Kampala, Uganda
Moses Joloba, MBChB, PhD , Makerere University, Kampala, Uganda
Curtis Donskey , Louis Stokes Cleveland VA Medical Center, Cleveland, OH
Background: Mulago Hospital is a 1500-bed, national referral hospital in Kampala, Uganda.  Patients seeking healthcare are triaged at the hospital’s Assessment Center and Casualty Department.  The hospital has four major clinical departments that include Medicine, Surgery, Obstetrics & Gynecology, and Pediatrics. Empiric antimicrobial therapy for infections at Mulago Hospital does not typically include coverage of MRSA. While laboratory capacity exists to perform active surveillance for MRSA at Mulago Hospital, financial resources do not.

Objective: To determine the prevalence of nasal carriage of Methicillin-Resistant Staphylococcus aureus (MRSA) in health-seeking patients and healthcare workers at Mulago Hospital in Kampala, Uganda.

Methods: Between June and February 2009, all Health Care Workers (HCWs) at Mulago Hospital, mainly nurses and physicians, and a random sample of patients seeking healthcare at the hospital’s Assessment Center and Casualty Department were recruited into the study.  The anterior nares were swabbed and streaked onto ChromAgarTM plates containing 10 µg/mL of cefoxitin and incubated at 37°C for 48 hours.  Colonies consistent with Staphylococcus aureus were subjected to identification and susceptibility testing.  All participants were asked to report their age, education, occupation, and history of travel (12 months), antibiotic use (12 months), hospitalization (12 months), medical conditions (6 months), and surgery (24 months).  Prevalence of MRSA colonization was compared across groups using Pearson’s chi-square and Fisher’s exact testsLogistic regression was used to estimate the odds of MRSA colonization associated with factors of interest.
Results: Overall, 110 HCWs and 354 health-seeking patients were recruited in the study.  Six (5.5%; 95% CI: 1.1%, 9.8%) HCWs and 41 (11.6%; 95% CI: 8.2%, 14.9%) patients were found to be colonized with MRSA.  Prevalence of MRSA colonization was similar among patients recruited from the Assessment Center and Casualty Department (12.4% vs. 11.0%; p=0.684).  Men were more likely than women to be colonized by MRSA: 7.7% vs. 1.4% among HCWs (p=0.284); and 15.7% vs. 8.3% among patients (p=0.044).  Overall, odds of MRSA colonization were greater in men than in women (OR=2.5; 95% CI: 1.3, 5.0).  MRSA colonization was not statistically significantly associated with history of antibiotic use, hospitalization, medical conditions, or surgery, and other factors.

Conclusions: Our findings demonstrate that nasal carriage of MRSA is common in healthcare workers and patients seeking healthcare at Mulago Hospital in Kampala, Uganda, with a higher frequency of carriage in men than women. Future studies are needed to evaluate the incidence of infections due to MRSA in this population.