Bacterial contamination of disinfectants: prevalence and students’ compliance with infection control practices




biofilm-derived, saliva ejector


Contaminated disinfectants have been occasional vehicles of healthcare associated infections. To determine the presence and level of bacterial contamination of disinfectants used to decontaminate suction devices and to assess the extent to which students comply with infection control practices. A two-part cross-sectional descriptive study consisting of microbiological testing of disinfectants and a questionnaire based observation of students Unannounced observation of students disinfecting suction devices were recorded using a questionnaire. The process involved collecting a prepared disinfectant from a storage bin using a kitchen measuring jug. Specimens of disinfectants and swabs of jugs were collected for aerobic culture. Data pertaining to compliance with infection control practices was gathered. Only 33.6% of the students were observed unannounced. An overwhelming majority (84.9%) of students disinfected suction devices; 52% cleaned and disinfected the external surface of suction hoses and the spittoon bowl; 18.6% allowed the disinfectant to remain in the system long enough, and 14% advised their patients not to close their lips around the suction device. The majority of disinfectant samples (56.3%) as well jugs (55.6%) were contaminated with bacteria. Bacterial contamination of disinfectants was common in addition to poor compliance with infection control practices.


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Author Biography

SR Mthethwa, Sefako Makgatho Health Sciences University, Ga-Rankuwa, South Africa


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How to Cite

Madzivani, N., Mthethwa, S., & Sekati, E. (2024). Bacterial contamination of disinfectants: prevalence and students’ compliance with infection control practices. South African Dental Journal, 79(01), 11–16.