Stethoscope as a Vector for Infectious Disease

Bacterial Assessment of Stethoscopes Used by Healthcare Workers at a Tertiary Care Government Hospital in Bharatpur, Nepal

The transmission of healthcare-associated infections (HCAIs) in healthcare settings is a serious challenge in the medical fraternity. Medical devices, such as stethoscopes used by healthcare workers (HCWs), are likely to harbor a considerable number of pathogenic microbes, which may result in the transmission of HCAIs. This study sought to investigate bacterial contamination of stethoscopes used by HCWs at Bharatpur Hospital, Nepal. During the study period of 3 months from December 2019 to February 2020, a total of 87 stethoscopes were examined; bacterial pathogens were isolated and identified by culture and biochemical tests, and their susceptibilities against different antibiotics were determined using standard protocols of the Clinical and Laboratory Standards Institute (CLSI). The disc diffusion method was used primarily to screen for extended-spectrum beta-lactamase (ESBL)- and metallo-beta-lactamase (MBL)-producing isolates, followed by their confirmation using cephalosporin/clavulanate combination discs and the disc potentiation methods, respectively. In addition, molecular detection of blaCTX-M and blaVIM genes was performed using conventional polymerase chain reaction (PCR). Of the 87 stethoscopes examined, more than a quarter (28.7%) were colonized with different pathogenic bacteria. Bacterial contamination of stethoscopes was found to be significantly associated with various factors, such as disinfecting routine, method of disinfection, and department of the hospital (p < 0.05). A higher rate of bacterial contamination was observed on the diaphragm of the stethoscope (12.64%) and among HCWs who overlooked hand hygiene practices (45.45%). The prevalence of methicillin-resistant S. aureus (MRSA) was 44.44%, and approximately half of the Gram-negative isolates (47%) were multidrug resistant (MDR). Imipenem (81.25%) and chloramphenicol (83.33%) were found to be the most effective antibiotics for Gram-negative and Gram-positive bacteria, respectively. Phenotypic screening showed that 43.75% of isolates were ESBL producers, and 18.75% were MBL producers, but blaCTX-M and blaVIM genes were detected in only 31.25% and 6.25% of isolates, respectively. The results of the study call for effective stethoscope disinfection practices along with the judicious use of antibiotics by HCWs in order to minimize cross-contamination, emergence of resistance, and spread of nosocomial infections in clinical settings.

Microbiological Impacts of Decontamination of Stethoscopes and Assessment of Disinfecting Practices among Physicians in Pakistan: A Quality Improvement Survey

The study was conducted to determine bacterial contamination of stethoscopes used by doctors before and after disinfecting with isopropyl alcohol and analyze their practices of disinfecting stethoscopes. Samples from stethoscopes were taken before and after disinfecting with 70% isopropyl alcohol swab with the help of a sterile swab. All swabs were inoculated on Blood and MacConkey agar plates and were examined for growth. Stethoscopes of 78 doctors were sampled which included 45 (58%) males and 33 (42%) females. Before decontamination of diaphragms with isopropyl alcohol, 27 (34.6%) diaphragms had "growth" while 51 (65.4%) had "no growth." After decontamination with isopropyl alcohol, 5 (6.4%) had "growth" while 73 (93.6%) had "no growth." The most common microorganism isolated from stethoscopes' diaphragms was methicillin-resistant Staphylococcus epidermidis (MRSE), that is, 14 out of 78 (17.9%). The survey also evaluated factors associated with contamination of stethoscopes. Most doctors 71(91%) believe that stethoscopes can be a source of infection and 55.1% (N = 43) responded that both diaphragm and bell of stethoscopes can transmit infections. Many doctors (41%, N = 32) reported that "forgetfulness/laziness" was the barrier which they faced regarding stethoscope hygiene followed by "lack of time" (21.8%, N = 17). The contamination rate (66.6%) is highest in those doctors who are using their stethoscopes for 3-5 years. Of them, 30 doctors (38.5%) never decontaminated their stethoscopes among which 17 had growth in their stethoscopes before cleaning with isopropyl alcohol, while three had growth even after decontamination. Most doctors used sanitizer (29.5%) and isopropyl alcohol (25.6%) as cleaning agents.

Natural Rubber (NR) Latex Films with Antimicrobial Properties for Stethoscope Diaphragm Covers

Systematic disinfection of the stethoscope diaphragm is required to ensure that it does not act as a vector for cross-transmission of health-related diseases. Thus, an antimicrobial latex film could be used as a cover to inhibit pathogenic bacteria from growing on its surface. The aim of this work is to determine the antimicrobial activity and mechanical properties of antimicrobial natural rubber (NR) latex films with different types of antimicrobial agents (mangosteen peel powder (MPP), zinc oxide nanoparticles (ZnO NP), and povidone-iodine (PVP-I)). The antimicrobial loading was varied from 0.5, to 1.0, and 2.0 phr to monitor the effective inhibition of Gram-negative bacteria and fungi growth. For MPP and PVP-I antimicrobial agents, a loading of 2.0 phr showed good antimicrobial efficacy with the largest zone of inhibition. Simultaneously, ZnO NP demonstrated excellent antimicrobial activity at low concentrations. The addition of antimicrobial agents shows a comparable effect on the mechanical properties of NR latex films. In comparison to control NR latex film (29.41 MPa, 48.49 N/mm), antimicrobial-filled films have significantly greater tensile and tear strengths (MPP (33.84 MPa, 65.21 N/mm), ZnO NP (31.79 MPa, 52.77 N/mm), and PVP-I (33.25 MPa, 50.75 N/mm). In conclusion, the addition of antimicrobial agents, particularly ZnO NP, can be a better choice for NR latex films because they will serve as both an activator and an antimicrobial. In a clinical context, with regard to frequently used medical equipment such as a stethoscope, such an approach offers significant promise to aid infection control.

Impact of alcohol-based hand-rub disinfection on bacterial bioburden on stethoscopes in a real-world clinical setting

In this randomized study, use of alcohol-based hand-rub disinfection significantly reduced bacterial bioburden of stethoscopes in routine clinical use. Prior cleaning of stethoscopes on the study day did not affect baseline contamination rates, which suggests that the efficacy of alcohol disinfection is short-lived and may need to be repeated between patients.

Stethoscope disinfection is rarely done in Ethiopia: What are the associated factors?

Introduction

The stethoscope, which is non-critical medical devices and a symbol of healthcare, is likely to be contaminated by pathogenic microorganisms and can play a contributory role in the transmission of hospital-acquired infection. And regular cleaning of the diaphragm of the stethoscope with a suitable disinfectant is decisive. However, in the resource-constrained setting like many healthcare facilities in Ethiopia healthcare provider’s stethoscope disinfection practice and its associated factors have not been well studied so far. Therefore, this study sought to determine stethoscope disinfection practice and associated factors among the healthcare providers in Addis Ababa, Ethiopia.

Methods

A facility-based cross-sectional study was carried out between April and May 2016. For this study, 576 healthcare providers (physicians, health officers, nurses, midwives, and anesthesiologist) were included from 21 healthcare facilities in Addis Ababa. A pre-tested structured questionnaire was used for data collection. Descriptive statistics were computed. Bivariate and multivariable logistic regression analyses were used to identify factors that were significantly associated with stethoscope disinfection after every use.

Results

A total of 546 healthcare providers participated in this study, for a response rate of 94.7%. Two-fifths, 39.7% (95%CI: 35.9, 44.0%) of healthcare providers disinfecting their stethoscope after every use. And a significant number of participants 34.6% (95%CI: 30.8, 38.5%) never disinfect their stethoscope. Three out of four (76.0%) healthcare providers believe that stethoscope contamination can contribute to the transmission of infections. Safe infection prevention practice (AOR = 3.79, 95%CI: 2.45–5.84), awareness on infection prevention guideline (AOR = 1.93; 95%CI: 1.31, 2.82), and favorable attitude towards infection prevention (AOR = 1.73, 95%CI: 1.02, 2.93) were significantly associated with stethoscope disinfection after every use. The study also found that the odds of stethoscope disinfection were likely to be reduced by 79% among physicians than nurses (AOR = 0.21; 95%CI: 0.09, 0.49).

Conclusions

Only a small proportion of healthcare providers disinfect their stethoscopes after every use. Factors such as safe infection prevention practice, awareness on infection prevention guidelines, and favorable attitude towards infection prevention were the independent predictors of stethoscopes disinfection after every use. Hence, promotion of stethoscope hygiene along with an educational program to enhance disinfection compliance in healthcare facilities may have a positive effect.