Investigation of Staphylococcus aureus, prevailing in the environment of Khyber Teaching Hospital, Peshawar, Pakistan.

The hospital environment plays an important role in the spread of microorganisms, including multi drug resistant (MDR) strains. Patients can acquire Methicillin-Resistant Staphylococcus aureus (MRSA) which can reside in the clinical setup that are not cleaned and can spread through air droplets, bed clothing, and healthcare workers. The purpose of this study was to investigate the prevalence of S. aureus in the Khyber Teaching Hospital (KTH). A total of 200 samples were collected from the floor, walls, air and inanimate objects in different wards of the KTH, during May 2012 to September 2012. These samples were screened for the recovery of S. aureus. Recovered organisms were subjected to susceptibility testing and investigated for the detection of various toxin and antibiotic resistance genes by Polymerase Chain Reaction (PCR). A total of 64 samples yielded S. aureus, out of which 37 (57.81%) were proved as MRSA. No isolate was found resistant to Vancomycin, however 81.25% of the isolates were found susceptible to Linezolid and Amikacin. The susceptibility to Fusidic acid, Chloramphenicol, Rifampicin, Doxycycline and Meropenem was observed as 79.69%, 76.56%, 75.00, 73.44% and 68.75% respectively. The frequency of sea, seb and sec genes were 56.25%, 43.75% and 12.5% in the recovered isolates. Erm C was more prevalent (28.12 %) than the ermA and ermB. The prevalence of pvl in MRSA was 21.62 % which is less than 33.33% in the MSSA isolates. S. aureus and especially MRSA are frequently prevalent in the KTH. Therefore, every immune-compromised patient is prone to infections caused by S. aureus. This will lead to high morbidity/mortality rate, prolong hospital stay and add extra cost to the health system.