Disinfection of Ultrasound Transducers Using Non-Sterile Tissue Paper in Some Low-Cost Private Ultrasound Centres in Nigeria – Implications for Nosocomial Infection Management

Abstract

Background/Aims: The incidence of disease outbreaks in clinical settings arising from ultrasound
examinations is well documented, and is a source of worry. The ultrasound transducers and the coupling gel
are potential sources of these infections since they come in direct contact with the patient’s skin. In this
study, we examine the efficacy of the widespread practice of the use of plain non-sterile tissue paper in
some low cost private ultrasound centres in our locality as a method of disinfecting ultrasound transducers
after each use. Its potential impact on nosocomial infection management in clinical practice is also
examined.
Methods: Swab samples from convex ultrasound transducers before and after transabdominal scanning of
three consecutive patients were obtained from 10 different ultrasound centres in urban and rural areas of
Enugu state. Ultrasound coupling gel samples were equally obtained, and all samples cultured for bacteria
growth which was quantified in colony forming units per ml (cfu/ml) and reported in 1000/ml. Paired
sampled t-test was used to check for significance in reduction in bacterial load before and after the
transducer was cleaned.
Results: Nine different bacterial strains were isolated. Staphylococcus aureus and Klebsiella spp had the
highest percentage of occurrence in all centres. Significant bacteria growth was recorded in the morning
before the examination, and plain tissue paper significantly reduced the bacteria load in the ultrasound
transducer.
Conclusion: Even though disinfecting ultrasound transducers with non-sterile plain tissue paper alone is
statistically effective and has the potential to minimize nosocomial infection, it is however not clinically
effective and hence not advised.