Radiology imaging equipment and accessories as possible Fomites of Nosocomial pathogens

Abstract

Background: Hospital-acquired infections (HAIs) known as nosocomial infections are a major challenge within the health-care environment. Although investment and time are continually spent on the eradication of HAIs, the problem still exists. The European Centre for Disease Prevention and Control (2015) reported that annually, 4,100,000 patients in Europe acquire additional diseases during their stay in the hospital resulting in 14,700 deaths. Nosocomial infections therefore contribute to the imbalance between resources for the management of hospitals. This is a particular challenge in developing countries like those in Sub-Saharan Africa, of which Ghana is part and, where very limited resources are available for the high volume of patient output. Radiology is a high technology service department that provides imaging to numerous inpatients and outpatients on a continuous basis. This means that items in the radiology department may serve as possible reservoirs for the transmission of nosocomial pathogens from one individual to another. Where Radiology resides within a health-care system that is unable to give adequate attention to the spread of nosocomial infections or even to proper infection control measures, HAIs becomes a real possibility. Aims: The aim of this study was to determine whether radiology imaging equipment and accessories for general radiography are possible fomites of nosocomial pathogens. The study also aimed at investigating the effectiveness of the disinfectant chemical agents (chlorine bleach/sodium hypochlorite and methylated spirits) used for cleaning surfaces at the research site. Furthermore, the study aimed to observe the cleaning procedures and practises by radiographers in general radiography. Methodology: The design of this research included an observational and an experimental phase. The study was conducted in the radiology department of a Teaching Hospital (TH) in Ghana. Swabbing, using wet sterile swab sticks was the method for sample collection. This was done on one occasion without cleaning of the selected x-ray equipment and accessories and another occasion after cleaning with the department’s preferred disinfectant chemical agents. The swab samples were then taken to the microbiology laboratory of the University of Ghana for culturing and identification. MacConkey and blood agar media were used to prepare the culture media. The prepared media were put into petri dishes and swab samples were inoculated onto the culture plates. Culture plates were then incubated for 24 hours, at a temperature of 37ºC. At the end of the incubation period, the culture plates were viewed macroscopically under a bright light, to identify any bacterial growth; according to their colony forming characteristics. Seven radiographers (n=7) were observed for a period of one month on the current cleaning procedures and practises in the radiology department. How thoroughly the equipment and accessories were cleaned (how much time spent per item) was recorded. Damp dusting (using cotton wool moistened with methylated spirits or chlorine bleach), cleaning equipment using methylated spirits or chlorine bleach after each contact with body fluid, hands washing after each patient using water and liquid soap, washing of hand randomly after patients (or in between patients) using water and liquid soap, were observed and recorded. Data was captured and analysed using the IBM SPSS Statistics Version 25. Results: The selected radiology imaging equipment and accessories swabbed were found to be contaminated with pathogens. Organisms identified were Staphylococcus aureus, Coagulase-negative staphylococci, Bacillus species(spp.), Shigella spp., Shigella sonnei., Klebsiella spp., Salmonella Paratyphi A, Salmonella Typhi, Providencia rettgeri, Enterobacter spp. and Citrobacter spp. Staphylococcus aureus was the predominate pathogenic isolate identified. A significant number of the Staphylococcus aureus and CoNS isolated was methicillin-resistant. Bacillus spp. was the predominant non-pathogenic isolate identified in the study. Statistically there was no significant difference (p=0.5835) between the total number of occurrences of bacterial isolates in both rooms after decontamination. The observation phase demonstrated that no documented protocol or infection control procedures were available. It was further observed that only one of the seven radiographers washed his/her hands after each patient, but that all radiographers practised hand washing and equipment cleaning when the procedure involved body fluid from patients. Conclusion: The research established that radiologic equipment and accessories were often exposed to pathogens and are therefore possible fomites of nosocomial pathogens. The effectiveness of the cleaning agents (methylated spirits and chlorine bleach) was not adequate. Radiographers partially practised infection control measures. Based on the findings of this study it recommended that a policy and procedure must be prepared and an awareness campaign/training of radiographers conducted. Other cleaning agents must also be investigated in a comparative study to determine the most effective agent (but still affordable within the resource constrained environment).