Can diagnostic ultrasound scanners be a potential vector of opportunistic bacterial infection?

Abstract

Ultrasound examinations are recognised as being safe. The greatest epidemiological threat during the performance of examination is the transfer of pathogenic and opportunistic microorganisms between patients and from personnel to patients. Colonization of the skin with opportunistic bacteria of immunocompromised and high risk patients may lead to infection following an ultrasound scan. Aim: To identify and evaluate the strains of bacteria occurring on ultrasound equipment subjected to unexpected control performed by a local infectious diseases control team. We assumed that transducers, gel holders and gel bottles can be contaminated with normal human skin microflora. The remaining tested parts of the ultrasound equipment could possibly be contaminated with normal human skin microflora and other pathogens. Material and methods: The swabs were taken from ultrasound scanners located in various hospital settings, from out-patient based radiology scanning rooms to operating theatre, and cultured. Results: Among all isolated 23% strains were classified as environmental microflora; 8% as strains related to patient's skin contamination; and 13 % strains constituted pathogenic Gram-negative rods.. The remaining strains were classified as opportunistic flora 38%. High prevalence of opportunistic bacteria cultured in our study lead to the modification of the ultrasound cleaning procedures in both institutions and recommendation of the use of antibacterial wipes to clean all parts of ultrasound equipment in contact with patients' skin and examiners. Conclusions: Contamination not only affects parts of diagnostic equipment placed in direct contact with the patient, but also, those surfaces that only medical personnel have had contact with.

Minimizing cross transmission of SARS-CoV-2 in obstetric ultrasound during COVID-19 pandemic

“…During the pandemic of COVID-19, attention must be paid at collecting clinical and epidemiological indicators, i.e., respiratory symptoms, fever, recent travel history to area with serious outbreak, or contact with confirmed cases [33]. Patient under investigation (PUI) is defined as a suspected case on the basis of the followings; [1] pneumonia of unknown origin, or [2] fever (≥37.5°C) and/or respiratory symptoms, or [3] epidemiological correlation with the domestic mass outbreak or contact with a confirmed case of COVID-19 and exhibiting fever and/or respiratory symptoms within 14 days. Infection can be confirmed within 90 min by nasopharyngeal swab for detection of viralspecific RNA with real-time reverse transcription polymerase chain reaction (RT-PCR) [34].…”

“…The central air conditioning is generally closed vented, and without High Efficiency Particulate Air (HEPA) filtration to arrest very fine particle. There are repeated handling of transducers, machine console, keyboards, touch screens, trackballs, and recording devices [3,4]. Basic knowledge of infection prevention measures is usually lacking among ultrasound providers [5].…”

DEGUM Recommendations on Infection Prevention in Ultrasound and Endoscopic Ultrasound

“…Ganz überwiegend fanden sich in den anderen Fällen Koagulase-negative Staphylokokken [28]. Aus Australien wird über Kontaminationen von 60 % aller Schallköpfe nach abdominellen Untersuchungen berichtet [29], aus Polen von 42 -100 % der im Routinebetrieb untersuchten Schallköpfe [30]. Eine aktuelle, europäisch-amerikanische Untersuchung fand Schallköpfe tendenziell stärker mikrobiell kontaminiert als öffentliche Toiletten und Haltestangen in Bussen [31].…”

How do healthcare workers in diagnostic imaging minimise risks but maximise performance during the COVID‐19 pandemic?

“…The ultrasound examination involves close contact with a patient, and in the context of COVID‐19, disinfection of the ultrasound probe and machine is crucial, along with appropriate PPE to prevent infection transmission. Previous studies revealed that high‐touch surfaces of the ultrasound machine have a high prevalence of microorganisms 24,25 and hence may be a vector in the transmission of SARS‐CoV‐2. Furthermore, survey and interview‐based studies have highlighted that ultrasound practitioners have a gap in knowledge of basic infection prevention and control (IPC) measures and standardisation is required 26,27 .…”