Low-Complexity Physical Layer Security Scheme for Heterogeneous Cellular Networks based on Coordinated Precoding Design and Artificial Noise Generation

Staphylococcus aureus is a Gram-positive bacterium that causes minor skin infections to life-threatening diseases. It is transmitted through direct contact with fomites, such as computer peripherals and handrails. Treatment of S. aureus infections is generally straightforward, but is complicated by drug-resistant strains, particularly methicillin-resistant S. aureus (MRSA). The University of the Philippines Diliman (UP Diliman) has hundreds of computer service providers (CSPs) and public utility jeepneys (PUJs) regularly used by faculty, students, staff, and visitors. While no outbreaks of S. aureus and MRSA have been reported, the possibility of infection with this pathogen through CSPs and PUJs is very likely. The objectives of this study are to determine the carriage rates of S. aureus and MRSA in CSPs, computer peripherals, and handrails of PUJs inside UP Diliman, and to identify the risk factors associated with S. aureus and MRSA contamination. A total of 162 computer peripherals from 27 CSPs and 196 PUJ handrails were swabbed. S. aureus isolates were identified using colony morphology, biochemical tests, and amplification of the nuc gene, whereas MRSA isolates were identified using the cefoxitin challenge and amplification of the mecA gene. S. aureus was identified in 92.6% of CSPs, 36.4% of computer peripherals, and 7.1% of PUJs, while MRSA carriage was 3.1% in CSPs and 2% in PUJs. No signif icant associations between S. aureus/MRSA and the assessed risk factors were observed (p > 0.05). Results indicate that while S. aureus prevalence is relatively high, MRSA carriage is low in CSPs and PUJs in UP Diliman