Antibiotic Susceptibility Patterns of Bacterial Isolates Recovered from Used Manual Toothbrushes

• Asraa Faraj Mohammed

  Department of Microbiology, Faculty of Dentistry, University of Benghazi, Benghazi, Libya

  Author

• Mohamed M Bumadian

  Department of Botany, Faculty of Science, Benghazi University, Benghazi, Libya

  Author

• Fatema Salih Khalifa

  Medical laboratory, Nephrology Center at Alhwari Hospital, Benghazi, Libya

  Author

• Asmaa Elramli

  College of Science, Technology Gaminas, Department of Biomedical Science, Gaminas, Libya

  Author

• Kerlous Samy Hanna Ibrahim

  Faculty of Pharmacy, Libyan University of Modern Sciences and Technology, Benghazi, Libya

  Author

Used manual toothbrushes may harbor bacteria originating from the oral cavity and surrounding environment during routine use. This study aimed to investigate bacterial contamination of used manual toothbrushes after one month of regular use, identify the recovered bacterial isolates, and determine their antibiotic susceptibility patterns. A cross-sectional, laboratory-based study was conducted in Benghazi, Libya, from January 2021 to June 2022. One hundred participants aged 18–55 years used new manual toothbrushes for one month before the toothbrushes were collected and examined microbiologically. Bacterial culture, identification, and antibiotic susceptibility testing were performed using standard microbiological procedures and the Kirby Bauer disk diffusion method. Bacterial growth was detected on 73% of the examined toothbrushes, while 27% showed no bacterial growth. Gram-positive bacteria accounted for 60.3% of all examined toothbrushes, whereas Gram-negative bacteria accounted for 39.7%. Among the recovered bacterial isolates, Staphylococcus epidermidis was the most frequently identified organism, accounting for 20 isolates (27.4%), followed by Streptococcus viridans with 17 isolates (23.3%). Other recovered isolates included Klebsiella spp. (9 isolates, 12.3 %), Escherichia coli (8 isolates, 11 %), Staphylococcus aureus (7 isolates, 9.6 %), Pseudomonas spp. (6 isolates, 8.2 %), Acinetobacter spp. (4 isolates, 5.5 %), and Proteus spp. (2 isolates, 2.7 %). The highest susceptibility rates were observed for ciprofloxacin (63%) and ceftriaxone (53%), while the highest resistance rates were observed for cefoxitin (65%) and ceftazidime (57%). These findings demonstrate the bacterial isolates recovered from used manual toothbrushes exhibit variable antibiotic susceptibility patterns, highlighting the importance of characterizing their susceptibility profiles and promoting appropriate toothbrush hygiene, storage, regular replacement

1. Asraa Faraj Mohammed, Department of Microbiology, Faculty of Dentistry, University of Benghazi, Benghazi, Libya

   Department of Microbiology, Faculty of Dentistry, University of Benghazi, Benghazi, Libya

2. Mohamed M Bumadian, Department of Botany, Faculty of Science, Benghazi University, Benghazi, Libya

   Department of Botany, Faculty of Science, Benghazi University, Benghazi, Libya

3. Fatema Salih Khalifa, Medical laboratory, Nephrology Center at Alhwari Hospital, Benghazi, Libya

   Medical laboratory, Nephrology Center at Alhwari Hospital, Benghazi, Libya

4. Asmaa Elramli, College of Science, Technology Gaminas, Department of Biomedical Science, Gaminas, Libya

   College of Science, Technology Gaminas, Department of Biomedical Science, Gaminas, Libya

5. Kerlous Samy Hanna Ibrahim, Faculty of Pharmacy, Libyan University of Modern Sciences and Technology, Benghazi, Libya

   Faculty of Pharmacy, Libyan University of Modern Sciences and Technology, Benghazi, Libya

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