Methicillin Resistant Staphylococcus aureus Exposure Assessment in a Burn Center Environment Cassandra Andrade, Space Grant Intern Kelly Reynolds, Ph.D., Project Mentor

Overview Staphylococcus aureus Resistance Transmission/infection risks Need for Burn Center project Project Procedures Results Future Study

Staphylococcus aureus Gram positive organism Opportunistic pathogen Common on skin and in anterior of nose ~2 billion people worldwide carry organism Infections: –Skin boils –Bacteremia (sepsis) –pneumonia

Antibiotic Resistance & MRSA Organism no longer susceptible to antibiotics due to overexposure to antibiotics & exchange of genetic information between organisms More than 700,000 people die/year in U.S. of nosocomial antibiotic resistant infections Organism harder to treat Methicillin resistant S. aureus –First identified in a British hospital 1961 –53 billion people worldwide carry it –Transferable to sensitive S. aureus

Transmission & Acquisition Surface survival- “fomites” –Towels (damp), porous surfaces –Survival from days to weeks Skin-skin contact –Razors, poor hand washing –~ 10 organisms to cause infection Health care facilities (hospital-acquired) –staff hygiene –inadequate surface cleaning –Immunocompromised patients

Burn Center Extremely immunocompromised patients –Loss of #1 protection: skin –Co-morbid factors: Heavy steroids, immune suppressing therapies Other infections Invasive devices –Catheters –ventilators

Burn Center Project Why? –In the U.S. MRSA causes more deaths then AIDS –Patients dying from infections rather than injury –Present conflicts: staff hygiene vs. patients already have inactive infection vs. environment Treating patients that come in carrying the organism reduces infection vs. treatment doesn’t reduce infections Hypothesis: –Contaminated environmental surfaces are the major contributing factor to the number of patient infections

Project Preliminary environmental swabs 500 environmental surfaces –Patient areas: bed rails, pillows etc –Staff areas: offices, nurses stations etc. –Visitor areas: waiting room etc. Assess numbers of organisms Calculate exposure of patients and staff Genetic characterization

Procedures Surface samples collected with “Chem wipes” 100µL of sample spread plated onto NC Blood Agar Beta-hemolysis colonies streaked on to Trypticase Soy Agar Biochemical tests carried out: –Gram Stain –Catalase –Tube coagulase –Slide coagulase –Poly-B sensitivity –Oxicillin plate (final MRSA decipher)

Preliminary data & Results -11 out of 30 samples test positive for MRSA - identification of “hotspots” for next surface samples

Future Study Burn patient cultures and assessment of number of MRSA present Water testing of Burn center tub room water for presence of MRSA and top infectious pathogens

Questions??