Mobile phone bacterial contamination among students and staff at Haramaya University, Eastern Ethiopia

Mobile phones are used by most of the global population, particularly by college and university students and healthcare professionals. Despite their benefits, potential health risks associated with mobile-phone contamination may be overlooked. Therefore, this study aimed to determine bacterial contamination, associated factors, and antimicrobial susceptibility patterns of bacterial isolates from mobile phones among students and employees of Haramaya University College of Health and Medical Sciences, Harar, Eastern Ethiopia. An institution-based cross-sectional study was conducted among 238 students and employees from July 1 to August 30, 2022. Participants were selected using stratified sampling techniques. A structured questionnaire was used to collect the data. A swab sample was collected from each participant’s mobile phone using a sterilized cotton swab and transported to the laboratory within 2 hours for microbiological investigation. Bacterial isolates were identified using colony morphology, gram staining, and biochemical tests. Antimicrobial susceptibility testing was performed using the Kirby–Bauer disk diffusion method. Bivariable and multivariable logistic regression analyses were used to identify factors associated with bacterial contamination. Bacterial contamination was detected on 89.5% (95% confidence interval [CI]: 87–92) of sampled mobile phones. A total of 235 bacterial isolates were recovered, of which Staphylococcus epidermidis was the predominant isolate (70.6%), followed by Staphylococcus saprophyticus (14.9%) and Staphylococcus aureus (6.4%). Among the bacterial isolates tested for antimicrobial susceptibility, susceptibility was highest to gentamicin and chloramphenicol (94.0% each), followed by clindamycin (83.4%). Resistance was highest to ampicillin (98.7%), kanamycin (88.2%), cefotaxime (71.5%), cefoxitin (54.9%), and ciprofloxacin (52.8%). Overall, 181 (77.02%) isolates were multidrug-resistant, and 25 (10.64%) were extensively drug-resistant. Male sex (adjusted odds ratio [AOR]: 3.92, 95% CI: 1.364–11.282), lack of regular mobile-phone cleaning (AOR: 7.25, 95% CI: 2.161–24.336), and lack of awareness about mobile-phone bacterial contamination (AOR: 4.25, 95% CI: 1.293–13.970) were independently associated with bacterial contamination. This study demonstrated a high level of bacterial contamination of mobile phones among students and employees. S epidermidis was the predominant bacterial isolate. High levels of antimicrobial resistance were observed, particularly to ampicillin, kanamycin, and cefotaxime. The findings support the need to promote regular mobile-phone cleaning and improve awareness of mobile-phone hygiene.