How to reduce the exposure risk of medical staff from SARS-CoV-2 by reducing environmental contamination: Experience from designated hospitals in China

Radiology Department: A Potential Source of Multidrug-Resistant Microorganisms: A Cross-Sectional Study at Tertiary Hospital, Palestine

Introduction

Globally, healthcare facilities face a great challenge in the form of hospital-acquired infections (HAIs). Aside from the morbidity and mortality they cause, these illnesses are also extremely costly. Research on infection transmission in the medical field has been considerable, but not so much in the radiology department.

Aim

This study aims to identify the presence of multidrug-resistant (MDR) microbes on surfaces that are frequently touched in computed tomography (CT), magnetic resonance imaging (MRI), ultrasound (US), plain X-ray examination rooms, and portable radiography that are susceptible to contamination as well as to investigate the potential dangers of contracting MDR organisms to patients and healthcare providers. Materials and Method. In this study, 160 swab samples were collected from the radiology department during May and June 2022. Samples were obtained from 80 predefined surfaces twice within and outside of CT and MRI examination rooms as well as from US and plain X-ray machines and portable X-ray machines. Samples were taken at 7:00 a.m. using cotton swabs following the regular cleaning procedure. Bacterial colony-forming units (CFUs) per square centimeter were calculated after swabbing a 100 cm2 surface.

Results

Nearly all of the surfaces tested had bacterial CFUs. The highest contamination rate was found on keyboards ranging from (1.2-8) CFU/cm2, the sides of patient tables (1.2-20) CFU/cm2, knee coil (2.4-3) CFU/cm2, and patient leg supports (1.2-8) CFU/cm2. A noticeable increase in the contamination was noticed in June compared to May, and this was consistent with the increase in the number of isolated patients in the hospital, the workload in the radiology department, and the number of patients referred to the hospital. In our study, none of the examined sites showed contamination with MDR Gram-negative bacteria such as extended-spectrum beta-lactamases producing Enterobacterales (ESPL) or Carbapenemase-producing Enterobacterales (CPE). On the other hand, methicillin-resistant Staphylococcus (MRS), vancomycin-resistant Staphylococcus (VRS), and vancomycin-resistant Enterococcus (VRE) were detected.

Conclusion

All of the radiology department equipment and sites could be a source of bacterial infection including MDR, so the obligatory and committed disinfection protocol must be revised and implemented in the morning and between patients.

Contamination dynamics of personal protective equipment (PPE) by SARS-CoV-2 RNA in a makeshift hospital with COVID-19 positive occupants

Background

Personal protective equipment (PPE) helps protect healthcare workers (HCWs) from infection and prevents cross-contamination. Knowledge of the contamination dynamics of PPE during the management of COVID-19 patients in a makeshift hospital is limited.

Aim

To describe the rate of SARS-CoV-2 contamination in PPE and to assess the change of contamination at different time points.

Methods

HCWs were followed up for up to 4 hours with hourly collection of swab samples from PPE surfaces in a makeshift COVID-19 hospital setting. Swabs were tested using quantitative reverse transcription polymerase chain reaction (RT-qPCR) for SARS-CoV-2 RNA.

Results

SARS-CoV-2 was detected on 50.9% of the 1620 swabbed samples from 9 different sites of full-body PPE worn by HCWs. The proportion of sites contaminated with SARS-CoV-2 RNA varied from 10.6% to 95.6%. Viral RNA was most frequently detected from the sole of the outer foot cover (95.6%) and least frequently on the face shield (10.6%). The median Ct values among positive samples were 34.20 (IQR, 32.61-35.22) and 34.05 (IQR, 32.20-35.39) for ORF1ab and N genes, respectively. The highest rate of contamination with SARS-CoV-2 RNA for the PPE swab samples was found after 3 hours of use. The positive rate of outer surface of HEPA filters from air supply device was 82.1% during the full capacity period of the makeshift hospital.

Conclusion

A higher rate of contamination was identified at 3 hours after the entrance to the COVID-19 patient care area. Virus-containing aerosols were trapped in the HEPA filter of air supply equipment, representing a potential protective factor against infection to HCWs.