Investigation of a cluster of rapidly growing mycobacteria infections associated with joint replacement surgery in a Kentucky hospital, 2013-2014 with 8-year follow-up

BACKGROUND

We describe the investigation of a nosocomial outbreak of rapidly growing mycobacteria (RGM) infections and the results of mitigation efforts after 8 years.

METHODS

A cluster of RGM cases in a Kentucky hospital in 2013 prompted an investigation into RGM surgical site infections following joint replacement surgery. A case-control study was conducted to identify risk factors.

RESULTS

Eight cases were identified, 5 caused by M. wolinskyi and 3 by M. goodii. The case-control study showed the presence of a particular nurse in the operating room was significantly associated with infection. Environmental sampling at the nurse's home identified an outdoor hot tub as the likely source of M. wolinskyi, confirmed by pulsed-field gel electrophoresis and whole genome sequencing. The hot tub reservoir was eliminated, and hospital policies were revised to correct infection control lapses. No new cases of RGM infections have been identified as of 2021.

DISCUSSION

Breaches in infection control practices at multiple levels may have led to a chain of infection from a nurse's hot tub to surgical sites via indirect person-to-person transmission from a colonized health care worker (HCW).

CONCLUSIONS

The multifactorial nature of the outbreak's cause highlights the importance of overlapping or redundant layers of protection preventing patient harm. Future investigations of RGM outbreaks should consider the potential role of colonized HCWs as a transmission vector.

A cross-case analyses of laboratory professionals-patients interaction for patients accessing laboratory services at University of Cape Coast hospital and Ewim Polyclinic in the Cape Coast Metropolis, Ghana

Background

There is scarcity of data on experiences of patients who access laboratory services during hospital visits in sub-Saharan Africa. This study sought to evaluate the depth of laboratory professionals-patient interactions during pre- and post-sampling period at two hospitals in Ghana.

Methods

This study used real time observations of patient-laboratory staff interactions to collect first-hand data. Additionally, two separate sets of semi-structured questionnaires were used to collect data on the experiences of patients and laboratory professionals. Data were entered into Microsoft Excel and analysed using SPSS version 25.

Results

Inadequate laboratory space is a major factor limiting adequacy of patients-laboratory professionals’ interactions. Overall, even though the laboratory professionals (93.3%) overwhelmingly agreed to the need to inform patients about the turnaround time of the respective laboratory testing, this was not routinely done. Irrespective of patients’ educational attainment, patients were poorly informed about their respective laboratory tests. Although both patients and laboratory professionals (60.0% vs 63.6% respectively) indicated that the test requester has responsibility to inform patients about their laboratory testing, only 29.1% of patients indicated having received such explanations. Furthermore, although 28.1% of patients indicated knowing the specifics of their respective test requisition, only 15% could correctly identify their requested laboratory testing.

Conclusion

There is the need for standard operating protocols to standardize practitioner-patient interaction at the two facilities. Moreover, there is the need for laboratory staff-test requester engagement to clearly delineate who has what responsibilities regarding informing patients about laboratory testing.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-06560-8.

Aerosol generating procedures in trauma and orthopaedics in the era of the Covid-19 pandemic; What do we know?

Purpose

COVID-19 pandemic has created havoc all over the globe and spared no one regardless of status, gender, location and ethnicity. There were questions raised if trauma and orthopaedic (T&O) procedures actually generated aerosols? The need for a review of literature highlighting the nature and impact of aerosol generation within T&O surgery was noted.

Methods

A comprehensive online search was performed for all published articles in the English language, evaluating AGPs in T&O surgery and the relevant personal protection equipment used.

Results

The search strategy populated 43 studies. Six studies were identified as duplicates. The shortlisted 37 studies were screened and nine studies were included in the review. An additional four studies were included from the bibliography review.

Conclusion

Most orthopaedic procedures are high-risk aerosol generating procedures (AGPs). Conventional surgical masks do not offer protection against high-risk AGPs. In the current era of COVID-19 pandemic, there is a significant risk to the transmission of infection to the theatre staff. For protection against airborne transmission, appropriate masks should be used. These need proper fitting and sizing to ensure full protection when used.

Evidence of Long-Distance Aerial Convection of Variola Virus and Implications for Disease Control

Two distinct phenomena of airborne transmission of variola virus (smallpox) were described in the pre-eradication era-direct respiratory transmission, and a unique phenomenon of transmission over greater distances, referred to as "aerial convection". We conducted an analysis of data obtained from a systematic review following the PRISMA criteria, on the long-distance transmission of smallpox. Of 8179 studies screened, 22 studies of 17 outbreaks were identified-12 had conclusive evidence of aerial convection and five had partially conclusive evidence. Aerial convection was first documented in 1881 in England, when smallpox incidence had waned substantially following mass vaccination, making unusual transmissions noticeable. National policy at the time stipulated spatial separation of smallpox hospitals from other buildings and communities. The evidence supports the transmission of smallpox through aerial convection at distances ranging from 0.5 to 1 mile, and one instance of 15 km related to bioweapons testing. Other explanations are also possible, such as missed chains of transmission, fomites or secondary aerosolization from contaminated material such as bedding. The window of observation of aerial convection was within the 100 years prior to eradication. Aerial convection appears unique to the variola virus and is not considered in current hospital infection control protocols. Understanding potential aerial convection of variola should be an important consideration in planning for smallpox treatment facilities and protecting potential contacts and surrounding communities.

Indoor air quality-induced respiratory symptoms of a hospital staff in Iran

The ambient air of hospitals contains a wide range of biological and chemical pollutants. Exposure to these indoor pollutants can be hazardous to the health of hospital staff. This study aims to evaluate the factors affecting indoor air quality and their effect on the respiratory health of staff members in a busy Iranian hospital. We surveyed 226 hospital staff as a case group and 222 office staff as a control group. All the subjects were asked to fill in a standard respiratory questionnaire. Pulmonary function parameters were simultaneously measured via a spirometry test. Environmental measurements of bio-aerosols, particulate matter, and volatile organic compounds in the hospital and offices were conducted. T-tests, chi-square tests, and multivariable logistic regressions were used to analyze the data. The concentration of selected air pollutants measured in the hospital wards was more than those in the administrative wards. Parameters of pulmonary functions were not statistically significant (p > 0.05) between the two groups. However, respiratory symptoms such as coughs, phlegm, phlegmatic coughs, and wheezing were more prevalent among the hospital staff. Laboratory staff members were more at risk of respiratory symptoms compared to other occupational groups in the hospital. The prevalence of sputum among nurses was significant, and the odds ratio for the presence of phlegm among nurses was 4.61 times greater than office staff (p = 0.002). The accumulation of indoor pollutants in the hospital environment revealed the failure of hospital ventilation systems. Hence, the design and implementation of an improved ventilation system in the studied hospital is recommended.

[Evaluation of the quality of air in a surgical center of a hospital in the south of Brazil]

Objective The aim of this study was to evaluate the quality of air in surgical centre rooms of a hospital in the South of Brazil. Methods An evaluation of the parameters of comfortability (temperature, luminosity, concentration of carbon dioxide and relative humidity), microbiological analysis and chromatographic of the particulate material present in the filters of air conditioners was carried out. Results Regarding the aspects of comfortability, three surgical rooms did not present temperature in accordance to the current legislation, but were found within the ideal patterns in other environmental factors. In the analysis of particulate material, a larger number of fungal bio-aerosols of viscous colonies was obtained than filamentous. Conclusion It was found that the main aspects related to the quality of air in the hospital being studied are being accomplished; however there is a need of modifying building aspects in the surgical rooms in order to reduce the possibility of contamination by air and decrease the concentration of carbon dioxide in the environment.

High fungal spore burden with predominance of Aspergillus in hospital air of a tertiary care hospital in Chandigarh

The prevalence of fungal spores in the hospital air is essential to understand the hospital-acquired fungal infections. Air conditioners (ACs) used in hospitals may either reduce spores in air or be colonised by fungi and aid in its dissemination. The present study was conducted to assess the fungal spore burden in AC and non-AC areas. We found a high fungal spore count in air irrespective of whether the area was AC or non-AC. The most predominant species isolated were Aspergillus flavus and Aspergillus fumigatus. Such high concentrations of pathogenic fungi in air may predispose individuals to develop disease.

The extent of environmental and body contamination through aerosols by hydro-surgical debridement in the lumbar spine

INTRODUCTION

Surgical site infections occur in 1-6% of spinal surgeries. Effective treatment includes early diagnosis, parenteral antibiotics and early surgical debridement of the wound surface.

MATERIALS AND METHODS

On a human cadaver, we executed a complete hydro-surgery debridement including a full surgical setup such as draping. The irrigation fluid was artificially contaminated with Staphylococcus aureus (ATCC 6538). Surveillance cultures were used to detect environmental and body contamination of the surgical team.

RESULTS

For both test setups, environmental contamination was observed in an area of 6 × 8 m. Both test setups caused contamination of all personnel present during the procedure and of the whole operating theatre. However, the concentration of contamination for the surgical staff and the environment was lower when an additional disposable draping device was used.

CONCLUSIONS

The study showed that during hydro-surgery debridement, contaminated aerosols spread over the whole surgical room and contaminate the theatre and all personnel.

Nosocomial infection and its molecular mechanisms of antibiotic resistance

Nosocomial infection is a kind of infection, which is spread in various hospital environments, and leads to many serious diseases (e.g. pneumonia, urinary tract infection, gastroenteritis, and puerperal fever), and causes higher mortality than community-acquired infection. Bacteria are predominant among all the nosocomial infection-associated pathogens, thus a large number of antibiotics, such as aminoglycosides, penicillins, cephalosporins, and carbapenems, are adopted in clinical treatment. However, in recent years antibiotic resistance quickly spreads worldwide and causes a critical threat to public health. The predominant bacteria include Methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Acinetobacter baumannii. In these bacteria, resistance emerged from antibiotic resistant genes and many of those can be exchanged between bacteria. With technical advances, molecular mechanisms of resistance have been gradually unveiled. In this review, recent advances in knowledge about mechanisms by which (i) bacteria hydrolyze antibiotics (e.g. extended spectrum β-lactamases, (ii) AmpC β-lactamases, carbapenemases), (iii) avoid antibiotic targeting (e.g. mutated vanA and mecA genes), (iv) prevent antibiotic permeation (e.g. porin deficiency), or (v) excrete intracellular antibiotics (e.g. active efflux pump) are summarized.

A chemical free, nanotechnology-based method for airborne bacterial inactivation using engineered water nanostructures

Airborne pathogens are associated with the spread of infectious diseases and increased morbidity and mortality. Herein we present an emerging chemical free, nanotechnology-based method for airborne pathogen inactivation. This technique is based on transforming atmospheric water vapor into Engineered Water Nano-Structures (EWNS) via electrospray. The generated EWNS possess a unique set of physical, chemical, morphological and biological properties. Their average size is 25 nm and they contain reactive oxygen species (ROS) such as hydroxyl and superoxide radicals. In addition, EWNS are highly electrically charged (10 electrons per particle on average). A link between their electric charge and the reduction of their evaporation rate was illustrated resulting in an extended lifetime (over an hour) at room conditions. Furthermore, it was clearly demonstrated that the EWNS have the ability to interact with and inactivate airborne bacteria. Finally, inhaled EWNS were found to have minimal toxicological effects, as illustrated in an acute in-vivo inhalation study using a mouse model. In conclusion, this novel, chemical free, nanotechnology-based method has the potential to be used in the battle against airborne infectious diseases.

Aerobiology and its role in the transmission of infectious diseases

Aerobiology plays a fundamental role in the transmission of infectious diseases. As infectious disease and infection control practitioners continue employing contemporary techniques (e.g., computational fluid dynamics to study particle flow, polymerase chain reaction methodologies to quantify particle concentrations in various settings, and epidemiology to track the spread of disease), the central variables affecting the airborne transmission of pathogens are becoming better known. This paper reviews many of these aerobiological variables (e.g., particle size, particle type, the duration that particles can remain airborne, the distance that particles can travel, and meteorological and environmental factors), as well as the common origins of these infectious particles. We then review several real-world settings with known difficulties controlling the airborne transmission of infectious particles (e.g., office buildings, healthcare facilities, and commercial airplanes), while detailing the respective measures each of these industries is undertaking in its effort to ameliorate the transmission of airborne infectious diseases.

Collection of biological and non-biological particles by new and used filters made from glass and electrostatically charged synthetic fibers

Synthetic filters made from fibers carrying electrostatic charges and fiberglass filters that do not carry electrostatic charges are both utilized commonly in heating, ventilating, and air-conditioning (HVAC) systems. The pressure drop and efficiency of a bank of fiberglass filters and a bank of electrostatically charged synthetic filters were measured repeatedly for 13 weeks in operating HVAC systems at a hospital. Additionally, the efficiency with which new and used fiberglass and synthetic filters collected culturable biological particles was measured in a test apparatus. Pressure drop measurements adjusted to equivalent flows indicated that the synthetic filters operated with a pressure drop less than half that of the fiberglass filters throughout the test. When measured using total ambient particles, synthetic filter efficiency decreased during the test period for all particle diameters. For particles 0.7-1.0 mum in diameter, efficiency decreased from 92% to 44%. It is hypothesized that this reduction in collection efficiency may be due to charge shielding. Efficiency did not change significantly for the fiberglass filters during the test period. However, when measured using culturable biological particles in the ambient air, efficiency was essentially the same for new filters and filters used for 13 weeks in the hospital for both the synthetic and fiberglass filters. It is hypothesized that the lack of efficiency reduction for culturable particles may be due to their having higher charge than non-biological particles, allowing them to overcome the effects of charge shielding. The type of particles requiring capture may be an important consideration when comparing the relative performance of electrostatically charged synthetic and fiberglass filters.

PRACTICAL IMPLICATIONS

Electrostatically charged synthetic filters with high initial efficiency can frequently replace traditional fiberglass filters with lower efficiency in HVAC systems because properly designed synthetic filters offer less resistance to air flow. Although the efficiency of charged synthetic filters at collecting non-biological particles declined substantially with use, the efficiency of these filters at collecting biological particles remained steady. These findings suggest that the merits of electrostatically charged synthetic HVAC filters relative to fiberglass filters may be more pronounced if collection of biological particles is of primary concern.

Environmental monitoring in stem cell banks

The processing of stem cell lines for application in human therapy requires a physical environment in which air quality (i.e., the number of airborne particles) is controlled to minimize risk of contamination. The processing facility should be constructed and operated to minimise the introduction, generation and retention of particles and microorganisms. A formal program of environmental monitoring should be maintained in each stem cell bank to specify and assess key factors and their influence on the microbiological quality of the process and product. This program should assure the manipulation of cells involved in the derivation of stem cell lines and their culture under established limits for airborne particles and for microbial contamination of the air and surfaces. Environmental monitoring should also address the regulatory requirements in the countries in which the cells will be used. The monitoring programme will depend on local conditions in each processing centre or cell bank. Each centre will need to evaluate its specific needs and establish appropriate monitoring procedures which should not become intrusive to the extent that they might compromise the quality of the cell banks or products.

Environmental and body contamination through aerosols produced by high-speed cutters in lumbar spine surgery

STUDY DESIGN

A cadaver study to evaluate contamination in the operating room through the use of a high-speed bone cutter.

OBJECTIVES

To determine the grade of contamination of animate and inanimate objects through an aerosol intraoperatively, produced by a high-speed cutter during lumbar laminectomy.

SUMMARY OF BACKGROUND

In spinal surgery, high-speed cutters are used that produce an aerosol consisting of a mixture of irrigation solution, blood, and tissue debris. Such aerosols can be contaminated with potential pathogens. The surgical personnel and the environment are therefore exposed to a contamination risk.

METHODS

Laminectomies at three points (L2-L4) were performed on a human cadaver using a high-speed cutting device. The aerosol produced by the irrigation solution was contaminated with Staphylococcus aureus ATCC 12600. To detect the contamination of the environment and of the surgical team, surveillance cultures were used.

RESULTS

By air sampling, staphylococci were detected in the operating room at an extension of 5 by 7 m. The surgical team showed extensive face and body contamination with S. aureus. Despite protection by a barrier drape, similar contamination was observed on both the cadaver's head and the anesthesiologist.

CONCLUSIONS

The use of high-speed cutters in spinal surgery produces an aerosol that can be contaminated with blood-borne pathogens from infected patients. This aerosol is spread over the whole surgical room and contaminates the room and all personnel present. It is therefore critical to ensure that effective infection control measures are performed, not only by the surgeons but by everyone present in the operating room. The room itself must be sufficiently disinfected after such procedures.

Contamination risk of the surgical team through ROBODOC's high-speed cutter

During cutting of the femoral cavity in the ROBODOC procedure, an aerosol cloud of irrigation fluid, blood, and tissue debris was seen. This cloud potentially is contaminated with bacterial and viral vectors, which is an infection risk for the surgical team. A flat and a ball cutter were tested in four standard situations macroscopically with a colored solution. In a second experiment, the cutter was exposed to a fluid contaminated with Staphylococcus aureus, and bacterial room contamination was detected using standard cultures. The aerosol cloud was seen in a 6 x 3.6-m area. Extension and concentration varied, depending on the irrigation situation. ROBODOC's high-speed cutter produces an aerosol cloud in an area in which all members of the surgical team are affected. Sufficient protection is necessary for everyone in the operating room.

The index of microbial air contamination

The standard index of microbial air contamination (IMA) for the measurement of microbial air contamination in environments at risk is described. The method quantifies the microbial flow directly related to the contamination of surfaces coming from microbes that reach critical points by falling on to them. The index of microbial air contamination is based on the count of the microbial fallout on to Petri dishes left open to the air according to the 1/1/1 scheme (for 1h, 1m from the floor, at least 1m away from walls or any obstacle). Classes of contamination and maximum acceptable levels have been established. The index of microbial air contamination has been tested in many different places: in hospitals, in food industries, in art galleries, aboard the MIR space station and also in the open air. It has proved to be a reliable and useful tool for monitoring the microbial surface contamination settling from the air in any environment.

Airborne particulates in the OR environment

Intraoperative sampling of airborne particulates is rarely performed in the OR environment because of technical difficulties associated with sampling methodologies and because of the common belief that airborne contamination is infrequently associated with surgical site infections (SSIs). In this study, investigators recovered non-viable (i.e., lint) and viable (i.e., microorganisms) particulates during vascular surgery using a personal cascade impactor sampling device. The predominant nonviable particulates recovered during intraoperative sampling were wood pulp fibers from disposable gowns and drapes. Several potential nosocomial pathogens (e.g., Staphylococcus aureus, Staphylococcus epidermidis) and other drug-resistant isolates frequently were recovered from an area adjacent to the surgical field. The widespread presence of airborne particulates during surgery suggests that further studies are warranted to assess the role these particles may play in the development of SSIs or in dissemination of nosocomial pathogens within the OR and hospital environment.

Epidemiology of nosocomial fungal infections

This paper briefly reviews the current knowledge of the epidemiology and modes of transmission of nosocomial fungal infections and some of the therapeutic options for treating these diseases. In the mid-1980s, many institutions reported that fungi were common pathogens in nosocomial infections. Most, if not all, hospitals care for patients at risk for nosocomial fungal infections. The proportion in all nosocomial infections reportedly caused by Candida spp. increased from 2% in 1980 to 5% in 1986 to 1989. Numerous studies have identified common risk factors for acquiring these infections, most of which are very common among hospitalized patients; some factors act primarily by inducing immunosuppression (e.g., corticosteroids, chemotherapy, malnutrition, malignancy, and neutropenia), while others primarily provide a route of infection (e.g., extensive burns, indwelling catheter), and some act in combination. Non-albicans Candida spp., including fluconazole-resistant C. krusei and Torulopsis (C.) glabrata, have become more common pathogens. Newer molecular typing techniques can assist in the determination of a common source of infection caused by several fungal pathogens. Continued epidemiologic and laboratory research is needed to better characterize these pathogens and allow for improved diagnostic and therapeutic strategies.