OBJECTIVE 1.To investigate the prevalence of antibiotic resistant pattern of nasal S.aureus among year two medical student before and after hospital exposure 2.To identify the resistant rate against various types of antimicrobial agents used for treating Staphylococcus infections. 3 To correlate possible associations between the beta-lactamase production, and antibiotic susceptibility or resistance of S.aureus isolate. 4 To characterize and type the isolates of S.aureus in relation to beta-lactamase production. Conclusion RESULTS ANALYSIS Figure 2:Cephalosporin degradation by whole cell preparations that was monitored with spectrophotometer. DISCUSSION A carrier state of 23% was observed among our medical students with 21 to 23 years of age. The rate of carrier state of S.aureus in the anterior nares among the males and females before the hospital exposure was almost the same, 22.5% and 25.8% respectively. The isolates showed overall 68.2% resistance to amphicillin, 11.4% to erythromycin,9.1% to co-trimoxazole A total of sixteen(36.4%) were multi-drug resistant and only eight(18.2%) were fully susceptible to all the tested antimicrobial drugs. Out of the 44 S.aureus,22.7% showed mannitol fermentation and 13.6% showed positive growth on Brilliance MRSA 2 agar Significant correlation was observed between beta lactamase production and mannitol fermentation and growth on Brilliance MRSA 2 agar,(p<0.05) Measuring the relative rate of substrate hydrolysis for beta-lactamase typing, showed that 71.4% were type A beta-lactamase which is the most common serological type among the available beta-lactamase In conclusion, alarming rate of beta- lactamase positive nasal S.aureus were found among students who were attached with clinical postings. A high resistance was observed among commonly used beta- lactam antibiotics and significant percentage of them are found to be MRSA and having positive correlation with beta lactamase production. REFERENCE Prevalence of Antibiotic Resistance of Staphylococcus Aureus in Nasal Carriage after Hospital Exposure among Medical Students from AIMST University, Kedah Komathi, John Thambirajah, P.K Rajesh Faculty of Medicine,Unit of Microbilogy E mail:srkomathi@gmail.com   Experimental overview Figure 3: The beta-lactamase producing strains revealed a bimodal distribution in which the A and C enzyme-producing strains were distinct. Healthy carrier state of Staphylococcus aureus, including MRSA is a major concern (Sax et al,2007;Koh et al, 2009).Carrier rate of 11-32% were detected in general population(Chen et al,2012).In Malaysia dynamic transient colonization identified among Malaysian students (Neela et al.,2009).Though there are many reports regarding the carrier state of S.aureus among the doctors, nurses and other hospital employees. However, only scanty reports are available regarding such carrier state among the medical students. Data related to carriage pattern of S.aureus and MRSA among medical students are few (Santhosh,2008;Koh,2009;Nordin,2012).As far as is known, reports on the carrier state of S.aureus and MRSA before and after the hospital exposure are actually none from Malaysia. Neela .V, A. S. (2009). Highly Dynamic Transient Colonization of Staphylococcus aureus in Healthy Malaysian Student. Journal of Medical Microbiology , 1531-1532. Nordin S.A, N. A. (2012). Staphylococcus aureus Nasal Carriers Among Medical Students in A Medical School. Med J Malaysia , Vol 67 No 6 Koh et al.High prevalence of Methicillin-resistant Staphylococcus aureus (MRSA) on Doctor’s Neckties. Med J Malaysia Vol 64 No 3 September 2009. Santhosh D .V, S. K. (2008). Phenotypic Detection and Rate of Nasal Carriage of Heterotypic Borderline Oxacillin Resistant Staphylococcus aureus In Pre-clinical Medical Students from Malaysia. Journal of Clinical and Diagnostic Research , 985-990. Sax H, Allergens B, McKay I, Larson E, Boyce J, Pitted D. “My five moments for hand hygiene”: a user-centered design approach to understand, train, monitor and report hand hygiene. J Hosp Infect 2007; 67: 9–21. INTRODUCTION Figure 1:Comparison of the antibiotic susceptibility pattern of S.aureus before and after hospital exposure METHODOLOGY page 15