Mobile phones and computer keyboards: unlikely reservoirs of multidrug-resistant organisms in the tertiary intensive care unit

Bacterial contamination of healthcare workers' mobile phones in Africa: a systematic review and meta-analysis

BACKGROUND

Mobile phones are potential reservoirs for pathogens and sources of healthcare-associated infections. More microbes can be found on a mobile phone than on a man's lavatory seat, the sole of a shoe, or a door handle. When examining patients, frequent handling of mobile phones can spread bacteria. Nevertheless, evidence of bacterial contamination of mobile phones used by healthcare workers in Africa was inconclusive. Thus, this meta-analysis and systematic review was conducted to estimate the pooled prevalence of bacterial contamination of mobile phones used by healthcare workers and the most frequent bacterial isolates in Africa.

METHODS

We systematically retrieved relevant studies using PubMed/MEDLINE, POPLINE, HINARI, Science Direct, Cochrane Library databases, and Google Scholar from July 1, 2023 to August 08, 2023. We included observational studies that reported the prevalence of bacterial contamination of mobile phones among healthcare workers. The DerSimonian-random Laird's effect model was used to calculate effect estimates for the pooled prevalence of bacterial contamination in mobile phones and a 95% confidence interval (CI).

RESULTS

Among 4544 retrieved studies, 26 eligible articles with a total sample size of 2,887 study participants were included in the meta-analysis. The pooled prevalence of mobile phone bacterial contamination among healthcare workers was 84.5% (95% CI 81.7, 87.4%; I2 = 97.9%, p value < 0.001). The most dominant type of bacteria isolated in this review was coagulase-negative staphylococci (CONS) which accounted for 44.0% of the pooled contamination rate of mobile phones used by healthcare workers, followed by Staphylococcus aureus (31.3%), and Escherichia coli (10.7%).

CONCLUSIONS

In this review, the contamination of mobile phones used by HCWs with various bacterial isolates was shown to be considerable. The most prevalent bacteria isolates were coagulase-negative staphylococci, Staphylococcus aurous, and Escherichia coli. The prevalence of bacterial contamination in mobile phones varies by country and sub-region. Hence, healthcare planners and policymakers should establish norms to manage healthcare workers' hand hygiene and disinfection after using mobile phones.

Using adenosine triphosphate bioluminescence level monitoring to identify bacterial reservoirs during two consecutive Enterococcus faecium and Staphylococcus capitis nosocomial infection outbreaks at a neonatal intensive care unit

INTRODUCTION

This study aimed to assess the role of adenosine triphosphate (ATP) bioluminescence level monitoring for identifying reservoirs of the outbreak pathogen during two consecutive outbreaks caused by Enterococcus faecium and Staphylococcus capitis at a neonatal intensive care unit (NICU). The secondary aim was to evaluate the long-term sustainability of the infection control measures employed one year after the final intervention measures.

METHODS

Two outbreaks occurred during a 53-day period in two disconnected subunits, A and B, that share the same attending physicians. ATP bioluminescence level monitoring, environmental cultures, and hand cultures from healthcare workers (HCW) in the NICU were performed. Pulsed-field gel electrophoresis (PFGE) typing was carried out to investigate the phylogenetic relatedness of the isolated strains.

RESULTS

Four cases of E. faecium sepsis (patients A-8, A-7, A-9, B-8) and three cases of S. capitis sepsis (patients A-16, A-2, B-8) were diagnosed in six preterm infants over a span of 53 days. ATP levels remained high on keyboard 1 of the main station (2076 relative light unit [RLU]/100 cm2) and the keyboard of bed A-9 (4886 RLU/100 cm2). By guidance with the ATP results, environmental cultures showed that E. faecium isolated from the patients and from the main station's keyboard 1 were genotypically indistinguishable. Two different S. capitis strains caused sepsis in three patients. A total 77.8% (n = 7/9) of S. capitis cultured from HCW's hands were genotypically indistinguishable to the strains isolated from A-2 and A-16. The remaining 22.2% (n = 2/9) were genotypically indistinguishable to patient B-8. Three interventions to decrease the risk of bacterial transmission were applied, with the final intervention including a switch of all keyboards and mice in NICU-A and B to disinfectable ones. Post-intervention prospective monitoring up to one year showed a decrease in blood culture positivity (P = 0.0019) and catheter-related blood stream infection rate (P = 0.016) before and after intervention.

CONCLUSION

ATP monitoring is an effective tool in identifying difficult to disinfect areas in NICUs. Non-medical devices may serve as reservoirs of pathogens causing nosocomial outbreaks, and HCWs' hands contribute to bacterial transmission in NICUs.

Contamination by Antibiotic-Resistant Bacteria on Cell Phones of Vendors in a Peruvian Market

Background and Objectives. Multiple studies have evaluated the presence of bacterial contamination on cell phones in clinical settings; however, the presence and transmission of antibiotic-resistant bacteria on cell phones in the community have not been adequately elucidated. Material and Methods. A cross-sectional study was carried out to determine the presence of bacteria resistant to antibiotics on the cell phones of vendors in a Peruvian market and the associated factors. A sample of 127 vendors was obtained through stratified probabilistic sampling using a data collection form validated by experts. Cell phone samples were cultured using a standard technique, and antibiotic sensitivity was determined using the Kirby–Bauer technique. Chi-squared and Mann-Whitney U tests were used to determine factors associated with resistance in cell phone cultures. Results. Among the cell phones, 92.1% showed bacterial growth, predominantly Gram-positive bacteria (coagulase-negative staphylococci and Staphylococcus aureus), and 17% of the cultures showed resistance to at least three antibiotics evaluated. Two strains fell into the category of methicillin-resistant S. aureus, and three strains of E. coli had resistance to carbapenems. Conclusions. A short distance between customers and vendors, lack of a cell phone case, and having a cell phone with touchscreen are factors associated with antibiotic-resistant bacteria on cell phones.

Smartphones as an Ecological Niche of Microorganisms: Microbial Activities, Assembly, and Opportunistic Pathogens

Smartphone usage and contact frequency are unprecedentedly high in this era, and they affect humans mentally and physically. However, the characteristics of the microorganisms associated with smartphones and smartphone hygiene habits remain unclear. In this study, using various culture-independent techniques, including high-throughput sequencing, real-time quantitative PCR (RT-qPCR), the ATP bioluminescence system, and electron microscopy, we investigated the structure, assembly, quantity, and dynamic metabolic activity of the bacterial community on smartphone surfaces and the user's dominant and nondominant hands. We found that smartphone microbiotas are more similar to the nondominant hand microbiotas than the dominant hand microbiotas and show significantly decreased phylogenetic diversity and stronger deterministic processes than the hand microbiota. Significant interindividual microbiota differences were observed, contributing to an average owner identification accuracy of 70.6% using smartphone microbiota. Furthermore, it is estimated that approximately 1.75 × 106 bacteria (2.24 × 104/cm2) exist on the touchscreen of a single smartphone, and microbial activities remain stable for at least 48 h. Scanning electron microscopy detected large fragments harboring microorganisms, suggesting that smartphone microbiotas live on the secreta or other substances, e.g., human cell debris and food debris. Fortunately, simple smartphone cleaning/hygiene could significantly reduce the bacterial load. Taken together, our results demonstrate that smartphone surfaces not only are a reservoir of microbes but also provide an ecological niche in which microbiotas, particularly opportunistic pathogens, can survive, be active, and even grow. IMPORTANCE Currently, people spend an average of 4.2 h per day on their smartphones. Due to the COVID-19 pandemic, this figure may still be increasing. The high frequency of smartphone usage may allow microbes, particularly pathogens, to attach to-and even survive on-phone surfaces, potentially causing adverse effects on humans. We employed various culture-independent techniques in this study to evaluate the microbiological features and hygiene of smartphones, including community assembly, bacterial load, and activity. Our data showed that deterministic processes drive smartphone microbiota assembly and that approximately 1.75 × 106 bacteria exist on a single smartphone touchscreen, with activities being stable for at least 48 h. Fortunately, simple smartphone cleaning/hygiene could significantly reduce the bacterial load. This work expands our understanding of the microbial ecology of smartphone surfaces and might facilitate the development of electronic device cleaning/hygiene guidelines to support public health.

Approaches for characterizing and tracking hospital-associated multidrug-resistant bacteria

Hospital-associated infections are a major concern for global public health. Infections with antibiotic-resistant pathogens can cause empiric treatment failure, and for infections with multidrug-resistant bacteria which can overcome antibiotics of "last resort" there exists no alternative treatments. Despite extensive sanitization protocols, the hospital environment is a potent reservoir and vector of antibiotic-resistant organisms. Pathogens can persist on hospital surfaces and plumbing for months to years, acquire new antibiotic resistance genes by horizontal gene transfer, and initiate outbreaks of hospital-associated infections by spreading to patients via healthcare workers and visitors. Advancements in next-generation sequencing of bacterial genomes and metagenomes have expanded our ability to (1) identify species and track distinct strains, (2) comprehensively profile antibiotic resistance genes, and (3) resolve the mobile elements that facilitate intra- and intercellular gene transfer. This information can, in turn, be used to characterize the population dynamics of hospital-associated microbiota, track outbreaks to their environmental reservoirs, and inform future interventions. This review provides a detailed overview of the approaches and bioinformatic tools available to study isolates and metagenomes of hospital-associated bacteria, and their multi-layered networks of transmission.

Relationship between hand hygiene behavior and Staphylococcus aureus colonization on cell phones of nurses in the intensive care unit

Background

Healthcare-Associated Infections (HAIs) are infections that often occur in hospitals with Staphylococcus aureus as the primary cause. Staphylococcus aureus is usually found on nurses' hands and easily transferred by contact. Cell phones can be a convenient medium for transmitting bacteria. Accordingly, hand washing is one of the effective ways to prevent the transmission of Staphylococcus aureus.

Objective

This study aimed to determine the relationship between hand hygiene behavior and the colonization of Staphylococcus aureus on cell phones of nurses in the intensive care unit of the academic hospital.

Methods

This was an observational study with a cross-sectional design conducted from December 2019 to January 2020. The observations of hand hygiene behaviors were performed on 37 nurses selected using total sampling. Colonization of bacteria on each nurses' cell phone was calculated by swabbing the cell phones' surface. Colony counting was done using the total plate count method. Spearman Rank test and Mann Whitney test were used for data analysis.

Results

The nurses' hand hygiene behavior was 46.06%. Staphylococcus aureus colonization was found on 18.2% of the nurses' cell phones. However, there was no significant relationship between the nurses' hand hygiene behavior and the colonization of Staphylococcus aureus on their cell phones.

Conclusion

The hand hygiene behavior of nurses was still low, and there was evidence of Staphylococcus aureus colonization on their cell phones. As there was no relationship between the nurses' hand hygiene behavior with the colonization of Staphylococcus aureus on the cell phones, further research is needed to determine if there is an increase or decrease in colonization before and after regular observations.

Mobile phones represent a pathway for microbial transmission: A scoping review

BACKGROUND

Mobile phones have become an integral part of modern society. As possible breeding grounds for microbial organisms, these constitute a potential global public health risk for microbial transmission.

OBJECTIVE

Scoping review of literature examining microbial's presence on mobile phones in both health care (HC) and community settings.

METHODS

A search (PubMed&GoogleScholar) was conducted from January 2005-December 2019 to identify English language studies. Studies were included if samples from mobile phones were tested for bacteria, fungi, and/or viruses; and if the sampling was carried out in any HC setting, and/or within the general community. Any other studies exploring mobile phones that did not identify specific microorganisms were excluded.

RESULTS

A total of 56 studies were included (from 24 countries). Most studies identified the presence of bacteria (54/56), while 16 studies reported the presence of fungi. One study focused solely on RNA viruses. Staphylococcus aureus, and Coagulase-Negative Staphylococci were the most numerous identified organisms present on mobile phones. These two species and Escherichia coli were present in over a third of studies both in HC and community samples. Methicillin-resistant S. aureus, Acinetobacter sp., and Bacillus sp. were present in over a third of the studies in HC settings.

CONCLUSIONS

While this scoping review of literature regarding microbial identification on mobile phones in HC and community settings did not directly address the issue of SARS-CoV-2 responsible for COVID-19, this work exposes the possible role of mobile phones as a 'Trojan horse' contributing to the transmission of microbial infections in epidemics and pandemics.

Mobile phones as fomites for potential pathogens in hospitals: microbiome analysis reveals hidden contaminants

BACKGROUND

Smartphones used in clinical settings harbour potentially pathogenic bacteria, and this may pose an infection risk. Previous studies have relied on culture-based methods.

AIM

To characterize the quantity and diversity of microbial contamination of hospital staff smartphones using culture-dependent and culture-independent methods; to determine the prevalence of antibiotic-resistant potential pathogens; to compare microbial communities of hospital staff and control group phones.

METHODS

Smartphones of 250 hospital staff and 191 control group participants were swabbed. The antibiotic resistance profile of Staphylococcus aureus and Enterococcus isolates was determined. Swabs were pooled into groups according to the hospital area staff worked in, and DNA was extracted. The microbial community of the phone was characterized using an Illumina MiSeq metabarcoding pipeline.

FINDINGS

Almost all (99.2%) of hospital staff smartphones were contaminated with potential pathogens, and bacterial colony forming units (CFUs) were significantly higher on hospital phones than in the control group. Meticillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) were only detected on hospital mobile phones. Metabarcoding revealed a far greater abundance of Gram-negative contaminants, and much greater diversity, than culture-based methods. Bacillus spp. were significantly more abundant in the hospital group.

CONCLUSION

This study reinforces the need to consider infection-control policies to mitigate the potential risks associated with the increased use of smartphones in clinical environments, and highlights the limitations of culture-based methods for environmental swabbing.

Blue Light Disinfection in Hospital Infection Control: Advantages, Drawbacks, and Pitfalls

Hospital acquired infections (HAIs) are a serious problem that potentially affects millions of patients whenever in contact with hospital settings. Worsening the panorama is the emergence of antimicrobial resistance by most microorganisms implicated in HAIs. Therefore, the improvement of the actual surveillance methods and the discovery of alternative approaches with novel modes of action is vital to overcome the threats created by the emergence of such resistances. Light therapy modalities represent a viable and effective alternative to the conventional antimicrobial treatment and can be preponderant in the control of HAIs, even against multidrug resistant organisms (MDROs). This review will initially focus on the actual state of HAIs and MDROs and which methods are currently available to fight them, which is followed by the exploration of antimicrobial photodynamic therapy (aPDT) and antimicrobial blue light therapy (aBLT) as alternative approaches to control microorganisms involved in HAIs. The advantages and drawbacks of BLT relatively to aPDT and conventional antimicrobial drugs as well as its potential applications to destroy microorganisms in the healthcare setting will also be discussed.

Tracking Staphylococcus aureus in the intensive care unit using whole-genome sequencing

BACKGROUND

Staphylococcus aureus remains an important bacterial pathogen worldwide. This study utilized known staphylococcal epidemiology to track S. aureus between different ecological reservoirs in one 10-bed intensive care unit (ICU).

METHODS

Selected hand-touch surfaces, staff hands and air were screened systematically 10 times during 10 months, with patients screened throughout the study. S. aureus isolates were subjected to spa typing and epidemiological analyses, followed by whole-genome sequencing to provide single nucleotide polymorphism (SNP) data.

RESULTS

Multiple transmission pathways between patients and reservoirs were investigated. There were 34 transmission events, of which 29 were highly related (<25 SNPs) and five were possibly related (<50 SNPs). Twenty (59%) transmission events occurred between colonized patients and their own body sites (i.e. autogenous spread); four (12%) were associated with cross-transmission between patients; four (12%) occurred between patients and hand-touch sites (bedrails and intravenous pump); four (12%) linked airborne S. aureus with staff hands and bedrail; and two (6%) linked bed tables, bedrail and cardiac monitor.

CONCLUSION

Colonized patients are responsible for repeated introduction of new S. aureus into the ICU, whereupon a proportion spread to hand-touch sites in (or near) the patient zone. This short-term reservoir for S. aureus imposes a colonization/infection risk for subsequent patients. More than half of ICU-acquired S. aureus infection originated from the patients' own flora, while staff hands and air were rarely implicated in onward transmission. Control of staphylococcal infection in the ICU is best served by patient screening, systematic cleaning of hand-touch surfaces and continued emphasis on hand hygiene.

Microbiological colonization of healthcare workers' mobile phones in a tertiary-level Italian intensive care unit

BACKGROUND

Careful hand hygiene of healthcare workers is recommended to reduce transmission of pathogenic microorganisms to patients. Mobile phones are commonly used during work shifts and may act as vehicles of pathogens.

OBJECTIVE

To assess the colonizsation rate of intensive care unit healthcare workers' mobile phones before and after work shifts.

METHODS

Prospective observational study conducted in an academic, tertiary-level intensive care unit. Healthcare workers (including doctors, nurses and healthcare assistants) had their mobile phones sampled for microbiology before and after work shifts. Samples were taken with a swab in a standardizsed modality.

RESULTS

Fifty healthcare workers participated in the study (91% of the department staff). One hundred swabs were taken from 50 mobile phones. Forty-three healthcare workers (86%) reported a habitual use of their phones during the work shift. All phones (100%) were positive for bacteria. The most frequently isolated bacteria were Coagulase Negative Staphylococci, Bacillus sp. and Methicillin-resistant Staphylococcus aureus (97%, 56%, 17%, respectively). No patient admitted to the intensive care unit during the study period was positive for bacteria found on healthcare workers' mobile phones. No difference in bacteria types and burden was found between the beginning and the end of work shifts.

CONCLUSION

Healthcare workers' mobile phones are colonized even before the work shift and irrespective of the patients' microbiological flora.

Bacterial colonization of healthcare workers' mobile phones in the ICU and effectiveness of sanitization

Extra-European studies report high rates of multi-drug resistant bacteria colonization of healthcare workers' mobile phones in intensive care units. We aimed to assess the prevalence of bacterial colonization of healthcare workers' mobile phones in an intensive care unit in France and the effectiveness of a sanitization product. We designed a prospective, monocentric study in a 15-bed intensive care unit within a 300-bed private hospital. Bacterial colonization was assessed on 56 healthcare workers' mobile phones immediately before and 5 min after sanitization of the phones with bactericidal wipes. The mobile phones of 42 administrative staff acted as controls. All mobile phones in both groups were colonized. Healthcare workers' phones had a higher number of different bacterial species per phone (2.45 ± 1.34 vs. 1.81 ± 0.74, p = 0.02). Colonization with pathogens did not differ significantly between healthcare workers' and controls' phones (39.3% vs. 28.6%, p = 0.37). Excluding coagulase negative Staphylococcus, Staphylococcus aureus was the most common pathogen found in both groups (19.6% and 11.9%, p = 0.41). Only one healthcare workers' mobile phone was colonized by methicillin-resistant Staphylococcus aureus, and no other multi-drug resistant bacteria was detected. No covariate was associated with pathogen colonization. After sanitization, 8.9% of mobile phones were sterilized, and colonization with pathogenic bacteria decreased (21.4% vs. 39.3%, p = 0.04) as did the number of CFUs/mL (367 ± 404 vs. 733 ± 356, p < 0.001). Colonization of intensive care unit healthcare workers' and administrative staff's mobile phones was similar. Colonization with pathogens was frequent but colonization with multi-drug resistant bacteria was rare. Disinfecting the phones with bactericidal wipes is not completely effective. Specific sanitization protocols and recommendations regarding the management of healthcare workers' mobile phones in intensive care units should be developed. Additionally, good hand hygiene after touching mobile phones should be kept in mind to prevent cross-infections.

Microbial Exchange via Fomites and Implications for Human Health

PURPOSE OF REVIEW

Fomites are inanimate objects that become colonized with microbes and serve as potential intermediaries for transmission to/from humans. This review summarizes recent literature on fomite contamination and microbial survival in the built environment, transmission between fomites and humans, and implications for human health.

RECENT FINDINGS

Applications of molecular sequencing techniques to analyze microbial samples have increased our understanding of the microbial diversity that exists in the built environment. This growing body of research has established that microbial communities on surfaces include substantial diversity, with considerable dynamics. While many microbial taxa likely die or lay dormant, some organisms survive, including those that are potentially beneficial, benign, or pathogenic. Surface characteristics also influence microbial survival and rates of transfer to and from humans. Recent research has combined experimental data, mechanistic modeling, and epidemiological approaches to shed light on the likely contributors to microbial exchange between fomites and humans and their contributions to adverse (and even potentially beneficial) human health outcomes.

SUMMARY

In addition to concerns for fomite transmission of potential pathogens, new analytical tools have uncovered other microbial matters that can be transmitted indirectly via fomites, including entire microbial communities and antibiotic-resistant bacteria. Mathematical models and epidemiological approaches can provide insight on human health implications. However, both are subject to limitations associated with study design, and there is a need to better understand appropriate input model parameters. Fomites remain an important mechanism of transmission of many microbes, along with direct contact and short- and long-range aerosols.

An Examination of Bacterial Contamination of Models Used in Anatomy Laboratories

Background

Bacterial, viral, and parasitic transmission is a common issue involving items that are used in crowded places and are touched. In this study, it was aimed to identify the types of bacteria on models used in anatomy laboratories and the types of bacteria that contaminate students' hands.

Methods

Swab samples were taken from 30 models used in the laboratory and from the dominant hands of 94 students prior to and after contact with the models and were examined in the microbiology laboratory.

Results

Five types of bacteria were isolated from the anatomy models: coagulase-negative staphylococcus, staphylococcus aureus, bacillus spp., enterococcus spp., and escherichia coli. Coagulase-negative staphylococcus, staphylococcus aureus, and bacillus spp. were isolated from the hands of the students before the contact, and additionally, enterococcus spp. were isolated after the contact. The hands were not found to be contaminated with escherichia coli originating from the models, whereas enterococcus spp. were found to be transmitted to the hands after the contact.

Conclusion

The necessity of washing hands before and after working on the models and the necessity of occasionally disinfecting the models have emerged.