Isolation, identification and antibiotic-resistance profiling of bacteria isolated from mobile phone surfaces in Karbala.

Due to the diverse environments that mobile phones are exposed to via human handling they become reservoirs of microorganisms. The objective of the current study was to determine the level and character of bacterial contamination on mobile phones by identifying bacterial strains, and the degree of antimicrobial susceptibility. A cross-sectional study was conducted from April to July 2025 where phones belonging to 115 individuals were randomly chosen from various departments and units at Kerbala University and swabbed. The VITEK 2 automated system was used to identify bacterial taxa and test for antimicrobial susceptibility, and 50 of the swabs exhibited bacterial growth. This confirms that mobile phones serve as reservoirs for bacteria, including commensal skin flora, opportunistic pathogens, and environmental isolates. Species of Staphylococcus (Staphylococcus warneri, Staphylococcus epidermidis, and Staphylococcus aureus) dominated, which reflects frequent contact with human skin. Clinically significant pathogens such as Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli were also detected, which raises concerns about their role in hospital-acquired infections and antibiotic resistance. The detection of environmental and waterborne bacteria (Aeromonas hydrophila, Pseudomonas stutzeri, and Brevundimonas diminuta) and uncommon isolates (Ewingella americana, Kocuria kristinae, and Enterococcus columbae) also confirms that contamination is potentially occurring via poor hygiene practice. Antibiotic resistance was determined against multiple antibiotics. Among those tested, all isolates were resistant against benzylpenicillin, while no resistance was observed against tigecycline.