Environmental contamination and hospital-acquired infection: factors that are easily overlooked

Reservoirs of Nosocomial Pathogens in Intensive Care Units: A Systematic Review

Background

Nosocomial pathogens are known to exacerbate morbidity and mortality in contemporary critical healthcare. Hospital fomites, which include inanimate surfaces, have been identified as "breeding grounds" for pathogens that cause nosocomial infections. This systematic review aimed to deliver incisive insights on nosocomial pathogens in intensive care units (ICUs) and the role of fomites as potential reservoirs for their transmission.

Method

An extensive exploration of electronic databases, including PubMed and Scopus, from 1990 to 2023, was carried out between 25th and 29th May 2023, per standard PRISMA guidelines. Information were extracted from articles that reported on fomites in the ICU. Studies that did not quantitatively report the fomite contamination, and those that exclusively took samples from patients in the ICU were excluded from the analysis.

Results

About 40% of the total samples collected on fomites from all the studies yielded microbial growth, with species of Staphylococcus being the most predominant. Other prevalent microbes were Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Candida spp., Enterococcus sp., and Enterobacter sp. The neonatal intensive care unit (NICU) had the highest proportion of contaminated fomites. Among known fomites, the sphygmomanometer exhibited a 100% detection rate of nosocomial pathogens. This included E. aerogenes, Staphylococcus aureus, coagulase-negative Staphylococci (CoNS), E. coli, and K. pneumoniae. Multidrug-resistant (MDR) bacteria, such as methicillin-resistant S. aureus (MRSA), vancomycin-resistant Enterococci (VRE), extended-spectrum beta-lactamase (ESBL)-producing E. coli, and MDR Pseudomonas aeruginosa were commonly isolated on fomites in the ICUs.

Conclusion

Many fomites that are readily used in patient care in the ICU harbour nosocomial pathogens. The most common fomite appeared to be mobile phones, sphygmomanometers, and stethoscopes, with Staphylococcus being the most common contaminant. Consequently, the need for rigorous disinfection and sterilization protocols on fomites in the ICU cannot be overemphasized. Additionally, heightened awareness on the subject among health professionals is crucial to mitigating the risk and burden of nosocomial infections caused by drug-resistant bacteria.

Patient Satisfaction With the Health Care Services of a Government-Financed Health Protection Scheme in Bangladesh: Cross-Sectional Study

BACKGROUND

Since 2016, the government of Bangladesh has been piloting a health protection scheme known as Shasthyo Surokhsha Karmasuchi (SSK), which specifically targets households living below the poverty line. This noncontributory scheme provides enrolled households access to inpatient health care services for 78 disease groups. Understanding patients' experiences with health care utilization from the pilot SSK scheme is important for enhancing the quality of health care service delivery during the national-level scale-up of the scheme.

OBJECTIVE

We aimed to evaluate patient satisfaction with the health care services provided under the pilot health protection scheme in Bangladesh.

METHODS

A cross-sectional survey was conducted with the users of the SSK scheme from August to November 2019. Patients who had spent a minimum of 2 nights at health care facilities were selected for face-to-face exit interviews. During these interviews, we collected information on patients' socioeconomic characteristics, care-seeking experiences, and level of satisfaction with various aspects of health care service delivery. To measure satisfaction, we employed a 5-point Likert scale (very satisfied, 5; satisfied, 4; neither satisfied nor dissatisfied, 3; dissatisfied, 2; very dissatisfied, 1). Descriptive statistics, statistical inferential tests (t-test and 1-way ANOVA), and linear regression analyses were performed.

RESULTS

We found that 55.1% (241/438) of users were either very satisfied or satisfied with the health care services of the SSK scheme. The most satisfactory indicators were related to privacy maintained during diagnostic tests (mean 3.91, SD 0.64), physicians' behaviors (mean 3.86, SD 0.77), services provided at the registration booth (mean 3.86, SD 0.62), confidentiality maintained regarding diseases (mean 3.78, SD 0.72), and nurses' behaviors (mean 3.60, SD 0.83). Poor satisfaction was identified in the interaction of patients with providers about illness-related information (mean 2.14, SD 1.40), availability of drinking water (mean 1.46, SD 0.76), cleanliness of toilets (mean 2.85, SD 1.04), and cleanliness of the waiting room (mean 2.92, SD 1.09). Patient satisfaction significantly decreased by 0.20 points for registration times of 16-30 minutes and by 0.32 points for registration times of >30 minutes compared with registration times of ≤15 minutes. Similarly, patient satisfaction significantly decreased with an increase in the waiting time to obtain services. However, the satisfaction of users significantly increased if they received a complete course of medicines and all prescribed diagnostic services.

CONCLUSIONS

More than half of the users were satisfied with the services provided under the SSK scheme. However, there is scope for improving user satisfaction. To improve the satisfaction level, the SSK scheme implementation authorities should pay attention to reducing the registration time and waiting time to obtain services and improving the availability of drugs and prescribed diagnostic services. The authorities should also ensure the supply of drinking water and enhance the cleanliness of the facility.

A multi-center cross-sectional study of Chinese Herbal Medicine-Drug adverse reactions using active surveillance in Singapore's Traditional Chinese Medicine clinics

BACKGROUND

This study aimed to investigate the rates and causality of patient-reported adverse events (AEs) associated with concomitant Chinese Herbal Medicine (CHM) and Western Medicine prescription drug (WMPD) consumption through active surveillance in Singapore's Traditional Chinese Medicine (TCM) clinics.

METHODS

A cross-sectional study was conducted at five TCM clinics across Singapore from 8th May till 8th July 2023. Patients were screened to determine rates of CHM and WMPD consumption, and then interviewed if an AE was reported. An expert committee assessed the AE reports to determine causality. Along with descriptive statistics, odds ratios were calculated to determine AE occurrence likelihoods for patients who consumed both CHM and WMPD compared to CHM consumption alone.

RESULTS

1028 patients were screened and 62.65% of them reported concurrent CHM-WMPD consumption. Patients who consumed CHM and WMPD were 3.65 times more likely to experience an AE as compared to CHM consumption alone. 18 AE reports were adjudicated, with most AEs deemed unlikely due to CHM consumption.

CONCLUSIONS

A large proportion of patients consumed CHM and WMPD concurrently, thus increasing their risk of experiencing AEs compared to those consuming CHM only. Active surveillance is applicable for detecting AEs, collecting data for causality assessment, and analysis.

Metabarcoding approach to identify bacterial community profiling related to nosocomial infection and bacterial trafficking-routes in hospital environments

Nosocomial infections (NIs) appear in patients under medical care in the hospital. The surveillance of the bacterial communities employing high-resolution 16S rRNA profiling, known as metabarcoding, represents a reliable method to establish factors that may influence the composition of the bacterial population during NIs. The present study aimed to utilize high-resolution 16S rRNA profiling to identify high bacterial diversity by analyzing 11 inside and 10 outside environments from the General Hospital of Ribeirão Preto Medical School, Brazil. Our results identified a high bacterial diversity, and among these, the most abundant bacterial genera linked to NIs were Cutibacterium, Streptococcus, Staphylococcus, and Corynebacterium. A Acinetobacter was detected in cafeterias, bus stops, and adult and pediatric intensive care units (ICUs). Data suggest an association between transport and alimentation areas proximal to the hospital ICU environment. Interestingly, the correlation and clusterization analysis showed the potential of the external areas to directly influence the ICU pediatric department microbial community, including the outpatient's clinic, visitor halls, patient reception, and the closest cafeterias. Our results demonstrate that high-resolution 16S rRNA profiling is a robust and reliable tool for bacterial genomic surveillance. In addition, the metabarcoding approach might help elaborate decontamination policies, and consequently reduce NIs.

Assessment of indoor air quality and their inter-association in hospitals of northern India-a cross-sectional study

This study was commenced to evaluate the indoor and outdoor air quality concentrations of PM_2.5, sub-micron particles (PM_>2.5, PM_1.0-2.5, PM_{0.50 -1.0}, PM_0.25-0.50, and PM_<0.25), heavy metals, and microbial contaminants along with their identification in three different hospitals of Lucknow City. The study was conducted from February 2022 to April 2022 in hospitals situated in the commercial, residential, and industrial belts of the city. The indoor concentration trend of particulate matter as observed during the study suggested that most of the highest concentrations belonged to the hospital situated in an industrial area. The highest obtained indoor and outdoor concentrations for PM_1.0-2.5, PM_0.50-1.0, PM_0.25-0.50, and PM_<0.25 are 40.44 µg/m³, 56.08 µg/m³, 67.20 µg/m³, 74.50 µg/m³, 61.9 µg/m³, 79.3 µg/m³, 82.0 µg/m³, and 93.9 µg/m³, respectively, which belonged to hospital C situated in the industrial belt. However, for PM_>2.5, the highest indoor concentration obtained belonged to hospital B, i.e., 30.7 µg/m³, which is situated in the residential belt of the city. Regarding PM_2.5, the highest indoor and outdoor concentrations obtained are 149.41 µg/m³ and 227.45 µg/m³, which were recorded at hospital A and hospital C, respectively. The present study also observed that a high bacterial load of 1389.21 CFU/m³ is recorded in hospital B, and the fungi load was highest in hospital C with 786.34 CFU/m³. Henceforth, the present study offers thorough information on the various air pollutants in a crucial indoor setting, which will further aid the researchers in the field to identify and mitigate the same more precisely.

Human microbiome and microbiota identification for preventing and controlling healthcare-associated infections: A systematic review

Objective

This systematic review describes the role of the human microbiome and microbiota in healthcare-associated infections (HAIs). Studies on the microbiota of patients, healthcare environment (HE), medical equipment, or healthcare workers (HCW) and how it could be transmitted among the different subjects will be described in order to define alarming risk factors for HAIs spreading and to identify strategies for HAIs control or prevention.

Methods

This review was performed in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. After retrieval in databases, identification, and screening of available records, 36 published studies were considered eligible and included in the review.

Results

A multifaceted approach is required and the analyses of the many factors related to human microbiota, which can influence HAIs onset, could be of paramount importance in their prevention and control. In this review, we will focus mainly on the localization, transmission, and prevention of ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) bacteria and Clostridium difficile which are the most common pathogens causing HAIs.

Conclusions

Healthcare workers' microbiota, patient's microbiota, environmental and medical equipment microbiota, ecosystem characteristics, ways of transmission, cleaning strategies, and the microbial resistome should be taken into account for future studies on more effective preventive and therapeutic strategies against HAIs.

Temporal variation in bacterial community profile on patients' bedsheets in a primary healthcare unit

Fabrics serve as fomites in spreading nosocomial infections. As a patient is in close contact with bedsheets, it is important to assess the seasonal variation in bacterial diversity on these in healthcare units. The study was conducted to characterise the bacterial diversity on patients' bedsheets across 7 months in a primary healthcare unit. Polyester-cotton blend fabric was stitched on bedsheets, and temporal dynamics of bacterial communities was assessed from May to November 2019. qPCR and amplicon sequencing of 16S rRNA gene was performed for profiling of bacterial community. Results revealed the dominance of Bacillota followed by Pseudomonadota, and Actinomycetota. A seasonal variation was observed in the bacterial load, with maximum values in June. This indicates the impact of environmental conditions on bacterial abundance and composition on fabrics in healthcare unit. The presence of priority pathogens on the patient bedsheets is a human health concern reiterating the need for season-specific laundering protocol.

A Systematic Literature Review of Indoor Air Disinfection Techniques for Airborne Bacterial Respiratory Pathogens

Interrupting the transmission of airborne (<≈5 µm) respiratory pathogens indoors is not a new challenge, but it has attracted unprecedented interest due to the COVID-19 pandemic during 2020–2021. However, bacterial respiratory pathogens with known or potential airborne transmission account for an appreciable proportion of the communicable disease burden globally. We aimed to systematically review quantitative, laboratory-based studies of air disinfection techniques for airborne respiratory bacteria. Three databases (PubMed, Web of Science, Scopus) were searched, following PRISMA guidelines. A total of 9596 articles were identified, of which 517 were assessed in detail and of which 26 met the inclusion and quality assessment criteria. Seven air disinfection techniques, including UV-C light, filtration, and face masks, among others, were applied to 13 different bacterial pathogens. More than 80% of studies suggested that air disinfection techniques were more effective at inactivating or killing bacteria than the comparator or baseline condition. However, it was not possible to compare these techniques because of methodological heterogeneity and the relatively small number of the studies. Laboratory studies are useful for demonstrating proof-of-concept and performance under controlled conditions. However, the generalisability of their findings to person-to-person transmission in real-world settings is unclear for most of the pathogens and techniques we assessed.

Indoor Air Quality in Healthcare Units—A Systematic Literature Review Focusing Recent Research

The adequate assessment and management of indoor air quality in healthcare facilities is of utmost importance for patient safety and occupational health purposes. This study aims to identify the recent trends of research on the topic through a systematic literature review following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) methodology. A total of 171 articles published in the period 2015–2020 were selected and analyzed. Results show that there is a worldwide growing research interest in this subject, dispersed in a wide variety of scientific journals. A textometric analysis using the IRaMuTeQ software revealed four clusters of topics in the sampled articles: physicochemical pollutants, design and management of infrastructures, environmental control measures, and microbiological contamination. The studies focus mainly on hospital facilities, but there is also research interest in primary care centers and dental clinics. The majority of the analyzed articles (85%) report experimental data, with the most frequently measured parameters being related to environmental quality (temperature and relative humidity), microbiological load, CO2 and particulate matter. Non-compliance with the WHO guidelines for indoor air quality is frequently reported. This study provides an overview of the recent literature on this topic, identifying promising lines of research to improve indoor air quality in healthcare facilities.

Microbiological Contamination of the Office Environment in Dental and Medical Practice

The microbiological contamination of the environment in independent healthcare facilities such as dental and general practitioner offices was poorly studied. The aims of this study were to describe qualitatively and quantitatively the bacterial and fungal contamination in these healthcare facilities and to analyze the antibiotic resistance of bacterial pathogens identified. Microbiological samples were taken from the surfaces of waiting, consulting, and sterilization rooms and from the air of waiting room of ten dental and general practitioner offices. Six surface samples were collected in each sampled room using agar contact plates and swabs. Indoor air samples were collected in waiting rooms using a single-stage impactor. Bacteria and fungi were cultured, then counted and identified. Antibiograms were performed to test the antibiotic susceptibility of bacterial pathogens. On the surfaces, median concentrations of bacteria and fungi were 126 (range: 0–1280) and 26 (range: 0–188) CFU/100 cm², respectively. In indoor air, those concentrations were 403 (range: 118–732) and 327 (range: 32–806) CFU/m³, respectively. The main micro-organisms identified were Gram-positive cocci and filamentous fungi, including six ubiquitous genera: Micrococcus, Staphylococcus, Cladosporium, Penicillium, Aspergillus, and Alternaria. Some antibiotic-resistant bacteria were identified in general practitioner offices (penicillin- and erythromycin-resistant Staphylococcus aureus), but none in dental offices. The dental and general practitioner offices present a poor microbiological contamination with rare pathogenic micro-organisms.

Indoor Air Quality in Healthcare and Care Facilities: Chemical Pollutants and Microbiological Contaminants

The indoor air quality of healthcare and care facilities is poorly studied. The aim of this study was to qualitatively and quantitatively describe the chemical pollution and the microbiological contaminations of the indoor environment of these facilities. Methods: A wide range of chemical compounds (39 volatile and 13 semi-volatile organic compounds, carbon dioxide, fine particulate matter) and microorganisms (fungi and bacteria) were studied. Sampling campaigns were conducted in two French cities in summer 2018 and winter 2019 in six private healthcare facilities (general practitioner’s offices, dental offices, pharmacies) and four care facilities (nursing homes). Results: The highest median concentrations of chemical compounds (μg/m3) were measured for alcohols (ethanol: 378.9 and isopropanol: 23.6), ketones (acetone: 18.8), aldehydes (formaldehyde: 11.4 and acetaldehyde: 6.5) and terpenes (limonene: 4.3). The median concentration of PM2.5 was 9.0 µg/m3. The main bacteria of these indoor environments were Staphylococcus, Micrococcus and Bacillus genera, with median bacterial concentrations in the indoor air of 14 cfu/m3. The two major fungal genera were Cladosporium and Penicillium, with median fungal concentrations of 7 cfu/m3. Conclusions: Indoor air in healthcare and care facilities contains a complex mixture of many pollutants found in higher concentrations compared to the indoor air in French hospitals in a previous study.

Virus matrix interference on assessment of virucidal activity of high-touch surfaces designed to prevent hospital-acquired infections

Objectives/purpose

High-touch surfaces are a critical reservoir in the spread of nosocomial infections. Although disinfection and infection control protocols are well developed, they lack the ability to passively reduce the pathogenic load of high-touch surfaces. Copper and its alloys have been suggested as a surface that exhibit continuous biocidal effects. Antimicrobial studies on these surfaces are prevalent, while virucidal studies are not as well explored. The goal of this study was to first determine the virucidal activity of a copper–nickel–zinc alloy and to then examine the effect of soiling and virus preparation on virucidal activity.

Methods

A baculovirus vector was used as an easily quantifiable model of an infectious enveloped animal cell virus. Droplets containing virus were deposited on surfaces and allowed to stay wet using humidity control or were dried onto the surface. Virus was then recovered from the surface and assayed for infectivity. To examine how the composition of the droplet affected the survival of the virus, 3 different soiling conditions were tested. The first two were recommended by the United States Environmental Protection Agency and the third consisted of cell debris resulting from virus amplification.

Results

A copper–nickel–zinc alloy was shown to have strong virucidal effects for an enveloped virus. Copper, nickel, and zinc ions were all shown to leach from the alloy surface and are the likely cause of virucidal activity by this surface. Virucidal activity was achieved under moderate soiling but lost under high soiling generated by routine virus amplification procedures. The surface was able to repeatably inactivate dried virus droplets under moderate soiling conditions, but unable to do so for virus droplets kept wet using high humidity.

Conclusion

Ion leaching was associated with virucidal activity in both wet and dried virus conditions. Soiling protected the virus by quenching metal ions, and not by inhibiting leaching. The composition of the solution containing virus plays a critical role in evaluating the virucidal activity of surfaces and surface coatings.

Ventilation-Associated Particulate Matter Is a Potential Reservoir of Multidrug-Resistant Organisms in Health Facilities

Most healthcare-associated infections (HCAIs) develop due to the colonisation of patients and healthcare workers by multidrug-resistant organisms (MDRO). Here, we investigated whether the particulate matter from the ventilation systems (Vent-PM) of health facilities can harbour MDRO and other microbes, thereby acting as a potential reservoir of HCAIs. Dust samples collected in the ventilation grilles and adjacent air ducts underwent a detailed analysis of physicochemical properties and biodiversity. All Vent-PM samples included ultrafine PM capable of reaching the alveoli. Strikingly, >70% of Vent-PM samples were contaminated, mostly by viruses (>15%) or multidrug-resistant and biofilm-producing bacterial strains (60% and 48% of all bacteria-contaminated specimens, respectively). Total viable count at 1 m from the ventilation grilles was significantly increased after opening doors and windows, indicating an association between air flow and bacterial contamination. Both chemical and microbial compositions of Vent-PM considerably differed across surgical vs. non-surgical and intensive vs. elective care units and between health facilities located in coal and chemical districts. Reduced diversity among MDRO and increased prevalence ratio in multidrug-resistant to the total Enterococcus spp. in Vent-PM testified to the evolving antibiotic resistance. In conclusion, we suggest Vent-PM as a previously underestimated reservoir of HCAI-causing pathogens in the hospital environment.

Forest Saccharomyces paradoxus are robust to seasonal biotic and abiotic changes

Microorganisms are famous for adapting quickly to new environments. However, most evidence for rapid microbial adaptation comes from laboratory experiments or domesticated environments, and it is unclear how rates of adaptation scale from human-influenced environments to the great diversity of wild microorganisms. We examined potential monthly-scale selective pressures in the model forest yeast Saccharomyces paradoxus. Contrary to expectations of seasonal adaptation, the S. paradoxus population was stable over four seasons in the face of abiotic and biotic environmental changes. While the S. paradoxus population was diverse, including 41 unique genotypes among 192 sampled isolates, there was no correlation between S. paradoxus genotypes and seasonal environments. Consistent with observations from other S. paradoxus populations, the forest population was highly clonal and inbred. This lack of recombination, paired with population stability, implies that selection is not acting on the forest S. paradoxus population on a seasonal timescale. Saccharomyces paradoxus may instead have evolved generalism or phenotypic plasticity with regard to seasonal environmental changes long ago. Similarly, while the forest population included diversity among phenotypes related to intraspecific interference competition, there was no evidence for active coevolution among these phenotypes. At least ten percent of the forest S. paradoxus individuals produced "killer toxins," which kill sensitive Saccharomyces cells, but the presence of a toxin-producing isolate did not predict resistance to the toxin among nearby isolates. How forest yeasts acclimate to changing environments remains an open question, and future studies should investigate the physiological responses that allow microbial cells to cope with environmental fluctuations in their native habitats.

Evaluation of the exposure risk of SARS-CoV-2 in different hospital environment

The ongoing coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has imposed a significant impact on social and economic activities. As a high infectious pathogen, the existence of SARS-CoV-2 in public space is very important for its transmission. During the COVID-19 pandemic, hospitals are the main places to deal with the diseases. In this work, we evaluated the exposure risk of SARS-CoV-2 in hospital environment in order to protect healthcare workers (HCWs). Briefly, air and surface samples from 6 different sites of 3 hospitals with different protection levels were collected and tested for the SARS-CoV-2 nucleic acid by reverse transcription real-time fluorescence PCR method during the COVID-19 epidemic. We found that the positive rate of SARS-CoV-2 nucleic acid was 7.7 % in a COVID-19 respiratory investigation wards and 82.6 % in a ICUs with confirmed COVID-19 patients. These results indicated that in some wards of the hospital, such as ICUs occupied by COVID-19 patients, the nucleic acid of SARS-CoV-2 existed in the air and surface, which indicates the potential occupational exposure risk of HCWs. This study has clarified retention of SARS-CoV-2 in different sites of hospital, suggesting that it is necessary to monitor and disinfect the SARS-CoV-2 in hospital environment during COVID-19 pandemic, and will help to prevent the iatrogenic infection and nosocomial transmission of SARS-CoV-2 and to better protect the HCWs.

Impact of HVAC-Systems on the Dispersion of Infectious Aerosols in a Cardiac Intensive Care Unit

At the end of 2019, a variation of a coronavirus, named SARS-CoV-2, has been identified as being responsible for a respiratory illness disease (COVID-19). Since ventilation is an important factor that influences airborne transmission, we proposed to study the impact of heating, ventilation and air-conditioning (HVAC) with a variable air volume (VAV) primary air system, on the dispersion of infectious aerosols, in a cardiac intensive care unit, using a transient simulation with computational fluid dynamics (CFD), based on the finite element method (FEM). We analyzed three scenarios that followed the dispersion of pathogen carrying expiratory droplets particles from coughing, from patients possibly infected with COVID-19, depending on the location of the patients in the intensive care unit. Our study provides the mechanism for spread of infectious aerosols, and possibly of COVID-19 infection, by air conditioning systems and also highlights important recommendations for disease control and optimization of ventilation in intensive care units, by increasing the use of outdoor air and the rate of air change, decreasing the recirculation of air and using high-efficiency particulate air (HEPA) filters. The CFD-FEM simulation approach that was applied in our study could also be extended to other targets, such as public transport, theaters, philharmonics and amphitheaters from educational units.

Infection prevention knowledge, practice, and its associated factors among healthcare providers in primary healthcare unit of Wogdie District, Northeast Ethiopia, 2019: a cross-sectional study

BACKGROUND

Adequate knowledge and safe practice of infection prevention among healthcare providers are vital to prevent nosocomial infections. Thus, this study aimed to assess the level of knowledge and practices of healthcare providers towards infection prevention and its associated factors in the health facilities of Wogdie District, Northern Ethiopia.

METHODS

Institution based cross-sectional study was conducted among 171 healthcare providers who were selected by a simple random sampling technique. Data were collected using interviewer-administered questionnaire. Multivariable logistic regression was performed to identify factors associated with knowledge and practice of infection prevention.

RESULT

About 70.8 and 55.0% of healthcare providers had adequate knowledge and safe practice of infection prevention respectively. Having infection prevention guideline (AOR = 3.65, 95% CI; 1.26, 10.54), taking infection prevention training (AOR = 2.2, 95% CI; 1.01, 4.75), having five years or more work experience (AOR = 1.52:95%CI; 1.13, 4.51), and working in maternity unit (AOR = 1.67:95%CI; 1.38-5.23) were positively associated with adequate knowledge of infection prevention. The odds of safe practice were higher in participants who received infection prevention training (AOR: 2.4; 95% CI; 1.01, 4.75) but lower among healthcare providers who are working in the facility which has no continuous water supply (AOR = 0.48:95% CI; 0.21, 0.83).

CONCLUSION

A significant proportion of healthcare providers had inadequate knowledge and unsafe practice of infection prevention. To improve healthcare worker's knowledge of infection prevention, adequate pre-service as well as on job training should be given.

Control and management of multidrug resistant Acinetobacter baumannii: A review of the evidence and proposal of novel approaches

Hospital-acquired infections are on the rise and are a substantial cause of clinical and financial burden for healthcare systems. While infection control plays a major role in curtailing the spread of outbreak organisms, it is not always successful. One organism of particular concern is Acinetobacter baumannii, due to both its persistence in the hospital setting and its ability to acquire antibiotic resistance. A. baumannii has emerged as a nosocomial pathogen that exhibits high levels of resistance to antibiotics, and remains resilient against traditional cleaning measures with resistance to Colistin increasingly reported. Given the magnitude and costs associated with hospital acquired infections, and the increase in multidrug-resistant organisms, it is worth re-evaluating our current approaches and looking for alternatives or adjuncts to traditional antibiotics therapies. The aims of this review are to look at how this organism is spread within the hospital setting, discuss current treatment modalities, and propose alternative methods of outbreak management.

Cartography of opportunistic pathogens and antibiotic resistance genes in a tertiary hospital environment

Although disinfection is key to infection control, the colonization patterns and resistomes of hospital-environment microbes remain underexplored. We report the first extensive genomic characterization of microbiomes, pathogens and antibiotic resistance cassettes in a tertiary-care hospital, from repeated sampling (up to 1.5 years apart) of 179 sites associated with 45 beds. Deep shotgun metagenomics unveiled distinct ecological niches of microbes and antibiotic resistance genes characterized by biofilm-forming and human-microbiome-influenced environments with corresponding patterns of spatiotemporal divergence. Quasi-metagenomics with nanopore sequencing provided thousands of high-contiguity genomes, phage and plasmid sequences (>60% novel), enabling characterization of resistome and mobilome diversity and dynamic architectures in hospital environments. Phylogenetics identified multidrug-resistant strains as being widely distributed and stably colonizing across sites. Comparisons with clinical isolates indicated that such microbes can persist in hospitals for extended periods (>8 years), to opportunistically infect patients. These findings highlight the importance of characterizing antibiotic resistance reservoirs in hospitals and establish the feasibility of systematic surveys to target resources for preventing infections.

Spatiotemporal characterization of microbial diversity and antibiotic resistance in a tertiary-care hospital reveals broad distribution and persistence of antibiotic-resistant organisms that could cause opportunistic infections in a healthcare setting.

Temporal variations in bacterial community diversity and composition throughout intensive care unit renovations

BACKGROUND

Inanimate surfaces within a hospital serve as a reservoir of microbial life that may colonize patients and ultimately result in healthcare associated infections (HAIs). Critically ill patients in intensive care units (ICUs) are particularly vulnerable to HAIs. Little is known about how the microbiome of the ICU is established or what factors influence its evolution over time. A unique opportunity to bridge the knowledge gap into how the ICU microbiome evolves emerged in our health system, where we were able to characterize microbial communities in an established hospital ICU prior to closing for renovations, during renovations, and then after re-opening.

RESULTS

We collected swab specimens from ICU bedrails, computer keyboards, and sinks longitudinally at each renovation stage, and analyzed the bacterial compositions on these surfaces by 16S rRNA gene sequencing. Specimens collected before ICU closure had the greatest alpha diversity, while specimens collected after the ICU had been closed for over 300 days had the least. We sampled the ICU during the 45 days after re-opening; however, within that time frame, the alpha diversity never reached pre-closure levels. There were clear and significant differences in microbiota compositions at each renovation stage, which was driven by environmental bacteria after closure and human-associated bacteria after re-opening and before closure.

CONCLUSIONS

Overall, we identified significant differences in microbiota diversity and community composition at each renovation stage. These data help to decipher the evolution of the microbiome in the most critical part of the hospital and demonstrate the significant impacts that microbiota from patients and staff have on the evolution of ICU surfaces. Video Abstract.

SARS-CoV-2 RNA detection of hospital isolation wards hygiene monitoring during the Coronavirus Disease 2019 outbreak in a Chinese hospital

OBJECTIVES

The aim of this paper was to monitor the presence of SARS-Cov-2 among hospital environment surfaces, sewage, and personal protective equipment (PPE) of staffs in isolation wards in the First Affiliated Hospital of Zhejiang University, China.

METHODS

Surfaces of objects were routinely wiped with 1000mg/L chlorine containing disinfectant. Air and sewage disinfection was proceeded routinely and strictly. Hospital environmental surfaces and PPE of staffs in isolation wards were sampled using swabs. The sewage from various inlet and outlets were sampled. The respiratory and stool specimens of patients were collected. The respiratory specimens of staffs in the isolation wards were also sampled once a week. Quantitative real-time reverse transcription PCR (qRT-PCR) methods were used to confirm the existence of SARS-Cov-2 RNA. Viral culture was done for the samples positive for SARS-Cov-2 RNA.

RESULTS

During the study period, 33 laboratory-confirmed patients were hospitalized in isolation wards in the hospital. None of SARS-Cov-2 RNA was detected among the 36 objects surface samples and 9 staffs PPE samples in isolation wards. Though the 3 sewage samples from the inlet of preprocessing disinfection pool were positive for SARS-CoV-2 RNA and the sample from the outlet of preprocessing disinfection pool was weakly positive, the sewage sample from the outlet of the last disinfection pool was negative. All of the 5 sewage samples from various points were negative by viral culture of SARS-Cov-2. None of the respiratory specimens of staffs in the isolation wards were positive.

CONCLUSIONS

Though SARS-Cov-2 RNA of the sewage samples were positive from inlets of the sewage disinfection pool and negative from the outlet of the last sewage disinfection pool, no viable virus was detected by culture. The monitoring data in this study suggested that the strict disinfection and hand hygiene could decrease the hospital-associated COVID-19 infection risk of the staffs in isolation wards.

The effect of copper-oxide-treated soft and hard surfaces on the incidence of healthcare-associated infections: a two-phase study

BACKGROUND

Copper-oxide-impregnated linens and hard surfaces within the hospital environment have emerged as a novel technology to reduce environmental contamination and thereby potentially reduce the risk of healthcare-associated infections (HCAIs).

METHODS

This was a two-phase study. Phase 1 was a prospective, cluster-randomized, cross-over clinical trial in which one pod (eight beds) of our general ICU (GICU) utilized copper-oxide-impregnated linens whereas the other pod (eight beds) used standard hospital linens. Phase 2 was a two-year before-after study, following the relocation of three ICUs into a new ICU tower in which all the hard surfaces were treated with copper oxide (in addition to copper-impregnated linens). HCAIs were recorded using the National Healthcare Safety Network definitions.

FINDINGS

A total of 1282 patients were enrolled in phase 1. There was no difference in the rate of HCAI between the patients who received standard compared with copper oxide linen. In phase 2 there was a significant reduction in the number of infections due to Clostridioides difficile (2.4 per 1000 vs 0.7 per 1000 patient-days; incidence rate ratio: 3.3; 95% confidence interval: 1.4-8.7; P = 0.002) but no difference in the rate of central-line-associated bloodstream infections nor of catheter-associated urinary tract infections.

CONCLUSION

Copper-oxide-impregnated linens alone had no effect on the rate of HCAI. Our data suggest that copper-oxide-treated hard surfaces reduced the rate of infections due to C. difficile; however, important confounders cannot be excluded.

Transmission of Vancomycin-Resistant Enterococci in the Hospital Setting: Uncovering the Patient-Environment Interplay

Vancomycin-resistant enterococci (VRE) are relevant nosocomial pathogens with an increasing incidence in the last decades. Their transmission is optimal in the hospital setting, as it offers two potential, large reservoirs that are closely related: susceptible patients and their environment. Here we investigate the role of the hospital environment in the nosocomial transmission of VRE by establishing concrete links between contaminated surfaces and colonized/infected patients in outbreak and non-outbreak settings. Environmental and patient VRE isolates were collected between 2013 and 2019 and analyzed by whole-genome sequencing (WGS), subsequent multilocus sequence typing (MLST), and core genome (cg) MLST. Pairs of isolates differing in <3 alleles were rated as closely related, making a transmission likely. Fifty-three environmental VRE isolates were analyzed. MLST sequence types (ST) ST203 (50.0%), ST192 (21.3%), ST117 (17.3%), ST721 (8.8%), ST80 (2%), and ST1489 (0.7%) were detected, carrying the resistance determinants vanA (72.7%), vanB (24%), or both (3.3%). Of the 53 environmental isolates, 51 were found to form five clusters with genetically related patient isolates (n = 97 isolates). WGS confirms the role of the environment in the transmission dynamics of VRE in both the outbreak and non-outbreak settings, highlighting the importance of prevention and control of VRE spread.

Interplay Between Patient Colonization and Environmental Contamination With Vancomycin-Resistant Enterococci and Their Association With Patient Health Outcomes in Postacute Care

Background

The clinical utility of patient and environmental surveillance screening for vancomycin-resistant enterococci (VRE) in the postacute care setting has not been definitively clarified. We assessed the longitudinal relationship between patient colonization and room contamination, and we established their association with unfavorable health outcomes.

Methods

Four hundred sixty-three postacute care patients were followed longitudinally from enrollment to discharge for up to 6 months. Multiple body and environmental sites were sampled at regular intervals to establish correlation between environmental contamination and patient colonization and with longer than expected stay, unplanned hospitalization, and infections adjusting for sex, age, race, Charlson’s comorbidity index, and physical self-maintenance score.

Results

New VRE acquisition was more likely in patients residing in contaminated rooms (multivariable odds ratio [OR] = 3.75; 95% confidence interval [CI], 1.98–7.11) and vice versa (OR = 3.99; 95% CI, 2.16–7.51). New acquisition and new contamination were associated with increased length of stay (OR = 4.36, 95% CI = 1.86–10.2 and OR = 4.61, 95% CI = 1.92–11.0, respectively) and hospitalization (OR = 2.42, 95% CI = 1.39–4.22 and OR = 2.80, 95% CI = 1.52–5.12). New-onset infections were more common with higher VRE burdens (15% in the absence of VRE, 20% when after VRE isolation only on the patient or only in the room, and 29% after VRE isolation in both the patient and the room).

Conclusions

Room contamination with VRE is a risk factor for patient colonization, and both are associated with future adverse health outcomes in our postacute care patients. Further research is warranted to establish whether VRE screening may contribute to better understanding of risk assessment and adverse outcome prevention in postacute care.

Evaluation of bacterial and fungal contamination of kitchens of Birjand University of Medical Sciences

Objective

This study aims to evaluate the total bacterial and fungal count of tools, devices and surfaces of kitchens of the centers affiliated to Birjand University of Medical Sciences. In this study, 200 samples from four kitchens of Birjand University of Medical Sciences were obtained. After the preparation of serial dilutions, samples were cultured in plate count agar (PCA) plates and Sabouraud dextrose agar (SDA). After incubation at 37 and 25 °C for 24–48 and 72–96 h respectively, the microbial and fungal colonies were counted.

Results

The mean bacterial and fungal count of kitchens was 7.7 * 10⁷ and 7.6 * 10⁴, respectively. The highest and lowest levels of bacterial contamination were related to tools/devices and cover of tools/work clothes and the highest and lowest levels of fungal count were related to forks and spoons and the tools and devices of the storage site. The rate of contamination in the kitchens of Birjand University of Medical Sciences was relatively high. Thus, serious, continuous and accurate monitoring of the units, training of people working in all stages of cooking and disinfection the tools and devices are essential for control and prevention of disease transmission.

Indoor Air Quality and Sustainability Management—Case Study in Three Portuguese Healthcare Units

Adequate management of indoor air quality (IAQ) in healthcare units has relevant impacts on sustainability performance due to its effects on patient safety, occupational health and safety, and energy consumptions. This study sought to identify improvement opportunities on IAQ management by collecting and analyzing experimental data of selected parameters in three healthcare units in Portugal: Two general hospitals and one primary healthcare center. Indoor air temperature, relative humidity, CO2, bacteria, and fungi concentrations were measured in summer and winter campaigns in June/July 2017 and in January/March 2018. Results show that the exclusive use of natural ventilation is not adequate when the affluence of users is high, but the analyzed parameters revealed acceptable results under low occupation intensity conditions. Results also show that keeping low indoor air relative humidity has a significant impact in reducing fungi concentration and that there is a significant correlation at the 0.05 level between indoor air CO2 concentration and bacterial loads. Therefore, as opportunities to improve sustainability, IAQ management in healthcare facilities should consider natural ventilation as a complement to mechanical ventilation systems and should focus on adequate control of indoor air relative humidity and CO2 concentration to reduce the risk of airborne infections.

Clients' Experience and Satisfaction of Utilizing Healthcare Services in a Community Based Health Insurance Program in Bangladesh

Background: Community-based health insurance is recognized as a promising tool for health system improvement for low-income people that improves the health status of enrolees and enhances productivity and labor supply. The experience and opinion of the clients who utilized health services through the insurance scheme are important for improving healthcare services, shaping health policies and providing feedback on the quality, availability, and responsiveness of healthcare services. However, studies focusing on clients' satisfaction provided by the health insurance scheme are still limited globally. Objective: To address this knowledge gap, this current study attempted to measure the degree of clients' satisfaction towards healthcare services and insurance scheme, based on their experience of health care which will serve the future reference point to implement potential quality improvement initiatives of community-based health insurance program. Methods: A cross-sectional household survey was conducted within the catchment area of a community-based health insurance pilot program named Labor Association for Social Protection (LASP) during April⁻June 2014 to compare the evaluation of healthcare services provided by LASP scheme. In the descriptive analyses, the characteristics of the study participants were presented regarding frequency and the percentages with 95% confidence interval. Spearman correlation analysis was conducted between the satisfaction score of each indicator and overall satisfaction score; multivariate linear regression analysis was used to identify the factors associated with overall health scheme satisfaction. Results: The overall satisfaction mean score was 4.17 ± 0.04 (95% CI: 4.08⁻4.26) out of 5.00. The most satisfied domains were related to the diagnostic services (4.46 ± 0.98), explanation about the prescribed medicine (4.23 ± 0.81), the surrounding environment of healthcare facility (4.21 ± 0.70) and the behavior of health personnel toward clients (4.18 ± 0.73). Conclusions: Our study observed that the overall satisfaction level towards health services is quite favorable, but satisfaction scores can still be improved. These findings could contribute towards developing and designing the healthcare services packages of community-based health scheme which is in line with the health care financing strategy of Bangladesh as well as the recommendation of the World Health Organization for developing social health insurance as part of path to Universal Health Coverage.

Clothing as a transport vector for airborne particles: Chamber study

Strong evidence suggests that clothing serves as a reservoir of chemical pollutants and particles, including bioaerosols, which may have health significance. However, little is known about the role that clothing may play as a transport vector for inhaled airborne particles. Here, we contribute toward bridging the knowledge gap by conducting experiments to investigate clothing release fraction (CRF), determined as the size-dependent ratio of released to deposited particulate matter in the diameter range 0.5-10 μm. In a fully controlled chamber with low background particle levels, we deployed a programmable robot to reproducibly quantify the size-dependent CRF as a function of motion type and intensity, dust loadings, and activity duration. On average, 0.3%-3% of deposited particles were subsequently released with fabric motion, confirming that clothing can act as a vehicle for transporting airborne particles. The CRF increased with the vigor of movement and with dust loading. Rubbing and shaking the fabric were more effective than fabric stretching in resuspending particles. We also found that most of the release happened quickly after the onset of the resuspension activity. Particle size substantially influenced the CRF, with larger particles exhibiting higher values.

The Role of Environmental Contamination in the Transmission of Nosocomial Pathogens and Healthcare-Associated Infections

PURPOSE OF REVIEW

The aim of this review is to highlight the role of environmental contamination in healthcare-associated infections (HAIs) and to discuss the most commonly implicated nosocomial pathogens.

RECENT FINDINGS

Recent studies suggest that environmental contamination plays a significant role in HAIs and in the unrecognized transmission of nosocomial pathogens during outbreaks, as well as ongoing sporadic transmission. Several pathogens can persist in the environment for extended periods and serve as vehicles of transmission and dissemination in the hospital setting. Cross-transmission of these pathogens can occur via hands of healthcare workers, who become contaminated directly from patient contact or indirectly by touching contaminated environmental surfaces. Less commonly, a patient could become colonized by direct contact with a contaminated environmental surface. This review describes the role of environmental contamination in HAIs and provides context for reinforcing the importance of hand hygiene and environmental decontamination for the prevention and control of HAIs.

Environmental Infection Prevention: Priorities of Patient Safety Collaboration

Although progress has been made in decreasing health care-associated infections (HAI) in intensive care unit (ICU) patients, there has been an increase in HAI caused by drug-resistant pathogens, particularly those that contaminate the environment such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, Pseudomonas spp, Acinetobacter spp, and Clostridium difficile. The ICU environment including sinks and medical equipment has been identified as being at risk for contamination and associated with cross-transmission of pathogens between the health care provider, the environment, and the patient. This article addresses the role of the ICU nurse as a team facilitator collaborating with environmental services, infection preventionists, and others to influence ICU design during preconstruction planning and unit environmental hygiene after construction to promote patient safety and prevent HAI associated with contaminated environments and equipment.

Factors influencing microbial colonies in the air of operating rooms

Background

The operating room (OR) of the hospital is a special unit that requires a relatively clean environment. The microbial concentration of an indoor OR extrinsically influences surgical site infection rates. The aim of this study was to use active sampling methods to assess microbial colony counts in working ORs and to determine the factors affecting air contamination in a tertiary referral medical center.

Methods

This study was conducted in 28 operating rooms located in a 3000-bed medical center in northern Taiwan. The microbiologic air counts were measured using an impactor air sampler from May to August 2015. Information about the procedure-related operative characteristics and surgical environment (environmental- and personnel-related factors) characteristics was collected.

Results

A total of 250 air samples were collected during surgical procedures. The overall mean number of bacterial colonies in the ORs was 78 ± 47 cfu/m³. The mean number of colonies was the highest for transplant surgery (123 ± 60 cfu/m³), followed by pediatric surgery (115 ± 30.3 cfu/m³). A total of 25 samples (10%) contained pathogens; Coagulase-negative staphylococcus (n = 12, 4.8%) was the most common pathogen. After controlling for potentially confounding factors by a multiple regression analysis, the surgical stage had the significantly highest correlation with bacterial counts (r = 0.346, p < 0.001). Otherwise, independent factors influencing bacterial counts were the type of surgery (29.85 cfu/m³, 95% CI 1.28–58.42, p = 0.041), site of procedure (20.19 cfu/m³, 95% CI 8.24–32.14, p = 0.001), number of indoor staff (4.93 cfu/m³, 95% CI 1.47–8.38, p = 0.005), surgical staging (36.5 cfu/m³, 95% CI 24.76–48.25, p < 0.001), and indoor air temperature (9.4 cfu/m³, 95% CI 1.61–17.18, p = 0.018).

Conclusions

Under the well-controlled ventilation system, the mean microbial colony counts obtained by active sampling in different working ORs were low. The number of personnel and their activities critically influence the microbe concentration in the air of the OR. We suggest that ORs doing complex surgeries with more surgical personnel present should increase the frequency of air exchanges. A well-controlled ventilation system and infection control procedures related to environmental and surgical procedures are of paramount importance for reducing microbial colonies in the air.

Sources and dynamics of fluorescent particles in hospitals

Fluorescent particles can be markers of bioaerosols and are therefore relevant to nosocomial infections. To date, little research has focused on fluorescent particles in occupied indoor environments, particularly hospitals. In this study, we aimed to determine the spatial and temporal variation of fluorescent particles in two large hospitals in Brisbane, Australia (one for adults and one for children). We used an Ultraviolet Aerodynamic Particle Sizer (UVAPS) to identify fluorescent particle sources, as well as their contribution to total particle concentrations. We found that the average concentrations of both fluorescent and non-fluorescent particles were higher in the adults' hospital (0.06×10⁶ and 1.20×10⁶  particles/m³ , respectively) than in the children's hospital (0.03×10⁶ and 0.33×10⁶  particles/m³ , respectively) (P<.01). However, the proportion of fluorescent particles was higher in the children's hospital. Based on the concentration results and using activity diaries, we were able to identify sources of particle production within the two hospitals. We demonstrated that particles can be easily generated by a variety of everyday activities, which are potential sources of exposure to pathogens. Future studies to further investigate their role in nosocomial infection are warranted.

Evaluation of bactericidal and anti-biofilm properties of a novel surface-active organosilane biocide against healthcare associated pathogens and Pseudomonas aeruginosa biolfilm

Healthcare acquired infections (HAI) pose a great threat in hospital settings and environmental contamination can be attributed to the spread of these. De-contamination and, significantly, prevention of re-contamination of the environment could help in preventing/reducing this threat. Goldshield (GS5) is a novel organosilane biocide marketed as a single application product with residual biocidal activity. We tested the hypothesis that GS5 could provide longer-term residual antimicrobial activity than existing disinfectants once applied to surfaces. Thus, the residual bactericidal properties of GS5, Actichlor and Distel against repeated challenge with Staphylococcus aureus ATCC43300 were tested, and showed that GS5 alone exhibited longer-term bactericidal activity for up to 6 days on 316I stainless steel surfaces. Having established efficacy against S. aureus, we tested GS5 against common healthcare acquired pathogens, and demonstrated that, on average, a 1 log¹⁰ bactericidal effect was exhibited by GS5 treated surfaces, although biocidal activity varied depending upon the surface type and the species of bacteria. The ability of GS5 to prevent Pseudomonas aeruginosa biofilm formation was measured in standard microtitre plate assays, where it had no significant effect on either biofilm formation or development. Taken together the data suggests that GS5 treatment of surfaces may be a useful means to reducing bacterial contamination in the context of infection control practices.

Cleanliness in context: reconciling hygiene with a modern microbial perspective

The concept of hygiene is rooted in the relationship between cleanliness and the maintenance of good health. Since the widespread acceptance of the germ theory of disease, hygiene has become increasingly conflated with sterilization. In reviewing studies across the hygiene literature (most often hand hygiene), we found that nearly all studies of hand hygiene utilize bulk reduction in bacterial load as a proxy for reduced transmission of pathogenic organisms. This treatment of hygiene may be insufficient in light of recent microbial ecology research, which has demonstrated that humans have intimate and evolutionarily significant relationships with a diverse assemblage of microorganisms (our microbiota). The human skin is home to a diverse and specific community of microorganisms, which include members that exist across the ecological spectrum from pathogen through commensal to mutualist. Most evidence suggests that the skin microbiota is likely of direct benefit to the host and only rarely exhibits pathogenicity. This complex ecological context suggests that the conception of hygiene as a unilateral reduction or removal of microbes has outlived its usefulness. As such, we suggest the explicit definition of hygiene as "those actions and practices that reduce the spread or transmission of pathogenic microorganisms, and thus reduce the incidence of disease."

The risk of HCV infection among health-care workers and its association with extrahepatic manifestations (Review)

Health care workers (HCWs) are frequently exposed to different biological agents during their activities and are frequently monitored. Among these infectious agents, human hepatitis C (HCV) can infect HCWs. In this review article, the risk of HCV infection among HCWs is discussed along with extrahepatic HCV-related malignancies, such as non‑Hodgkin lymphoma. Accidental contamination, represented by percutaneous and mucocutaneous infections is the main risk factor for such infection. The compliance of the protection procedures, included in the current regulation for HCWs, is the most important issue to reduce the risk of pathogen infections that in turn may produce reduction of infection‑associated malignancies.

A systematic review of waterborne infections from nontuberculous mycobacteria in health care facility water systems

Healthcare-acquired infections are an increasing problem for health care providers and policy makers. Water is an overlooked source of infectious microorganisms in health care facilities. Waterborne nontuberculous mycobacteria (NTM) are ubiquitous, and particularly problematic in health care facility water systems, and cause a variety of diseases. The purpose of this review is to assess health care associated NTM infections from health care facility water systems. We documented susceptible populations, modes of transmission, and the median attack rate (e.g. patients infected per patients exposed). We aimed to identify transmission risk factors and inform evidence-based policies for infection control and prevention. We searched Embase, PubMed, Web of Science and clinicaltrials.gov without date restrictions. English language articles with original data on NTM waterborne infections in health care settings were included. Randomized controlled trials, descriptive studies (case reports, case series), case-control studies, cohort studies, cross-sectional surveys, and quasi-experimental studies on nosocomial waterborne infections were included. Three investigators independently screened titles and abstracts for relevant articles, and one screened full-text articles. Data were extracted by one investigator, and a second confirmed accuracy for 10% of results. We included 22 observational studies. Immunocompromised, post-surgical, and hemodialysis patients were commonly affected populations. A range of exposure routes such as uncovered central venous catheters (CVCs), wound exposure, and contamination during surgical procedures was reported. The median attack rate was 12.1% (interquartile range, 11-27.2). Waterborne NTM infection affects susceptible patients through common, preventable exposure routes. Effective prevention strategies will require both medical and environmental health expertise, and inter-professional cooperation will optimize these efforts.

Longitudinal Metagenomic Analysis of Hospital Air Identifies Clinically Relevant Microbes

We describe the sampling of sixty-three uncultured hospital air samples collected over a six-month period and analysis using shotgun metagenomic sequencing. Our primary goals were to determine the longitudinal metagenomic variability of this environment, identify and characterize genomes of potential pathogens and determine whether they are atypical to the hospital airborne metagenome. Air samples were collected from eight locations which included patient wards, the main lobby and outside. The resulting DNA libraries produced 972 million sequences representing 51 gigabases. Hierarchical clustering of samples by the most abundant 50 microbial orders generated three major nodes which primarily clustered by type of location. Because the indoor locations were longitudinally consistent, episodic relative increases in microbial genomic signatures related to the opportunistic pathogens Aspergillus, Penicillium and Stenotrophomonas were identified as outliers at specific locations. Further analysis of microbial reads specific for Stenotrophomonas maltophilia indicated homology to a sequenced multi-drug resistant clinical strain and we observed broad sequence coverage of resistance genes. We demonstrate that a shotgun metagenomic sequencing approach can be used to characterize the resistance determinants of pathogen genomes that are uncharacteristic for an otherwise consistent hospital air microbial metagenomic profile.

Concentrations and Sources of Airborne Particles in a Neonatal Intensive Care Unit

Premature infants in neonatal intensive care units (NICUs) have underdeveloped immune systems, making them susceptible to adverse health consequences from air pollutant exposure. Little is known about the sources of indoor airborne particles that contribute to the exposure of premature infants in the NICU environment. In this study, we monitored the spatial and temporal variations of airborne particulate matter concentrations along with other indoor environmental parameters and human occupancy. The experiments were conducted over one year in a private-style NICU. The NICU was served by a central heating, ventilation and air-conditioning (HVAC) system equipped with an economizer and a high-efficiency particle filtration system. The following parameters were measured continuously during weekdays with 1-min resolution: particles larger than 0.3 μm resolved into 6 size groups, CO2 level, dry-bulb temperature and relative humidity, and presence or absence of occupants. Altogether, over sixteen periods of a few weeks each, measurements were conducted in rooms occupied with premature infants. In parallel, a second monitoring station was operated in a nearby hallway or at the local nurses' station. The monitoring data suggest a strong link between indoor particle concentrations and human occupancy. Detected particle peaks from occupancy were clearly discernible among larger particles and imperceptible for submicron (0.3-1 μm) particles. The mean indoor particle mass concentrations averaged across the size range 0.3-10 μm during occupied periods was 1.9 μg/m(3), approximately 2.5 times the concentration during unoccupied periods (0.8 μg/m(3)). Contributions of within-room emissions to total PM10 mass in the baby rooms averaged 37-81%. Near-room indoor emissions and outdoor sources contributed 18-59% and 1-5%, respectively. Airborne particle levels in the size range 1-10 μm showed strong dependence on human activities, indicating the importance of indoor-generated particles for infant's exposure to airborne particulate matter in the NICU.