Hospital Water Supply Research Articles

Risk of Potential Invasive Non-Tuberculous Mycobacterial Infection in Major Cardiothoracic Surgeries.

Nontuberculous Mycobacteria (NTM) commonly colonise municipal water supplies and cause healthcare-associated outbreaks. Although the infections are rare, they are associated with high mortality. Aerosolization of NTM from colonised Heater cooler devices causes invasive infections in cardiac surgery patients. These units are widely used in open-chest heart surgery as an essential part of extracorporeal circulation but have been suggested as being a risk for infection. Water disinfection as well as effective engineering-related mitigation strategies should be designed to decrease the burden of NTM in the hospital water supply. Key Words: Nontuberculous Mycobacteria, Heater cooler devices, Endocarditis, Water, Cardiothoracic surgeries.

Fungal contamination of the water distribution system of a tertiary hospital water supply system in a resource-limited setting.

Fungal contamination of hospital water distribution systems has been implicated in outbreaks of healthcare-associated infections. To evaluate the prevalence of fungi in the water distribution system of a tertiary hospital in Nigeria. This was a descriptive cross-sectional study. Swabs and water samples were collected from taps and faucets in the hospital categorized into low (Accidents and Emergency Unit, Children Emergency Unit, Acute Stroke Unit and the 24 in-patient hospital wards) and high-risk (Renal Dialysis Unit, Central Sterile Services Department, Theatres and Intensive Care Units (ICUs)) units based on the vulnerability of patients being managed there. The membrane filtration method for water analysis was used. Where possible, isolates cultured were identified to species level. In total, 105 water and 49 swab samples were collected for analysis. All analysed water samples grew fungi. A total of 289 (high-risk; n = 178; low-risk; n = 111) and 76 fungi isolates were recorded from water and swab samples, respectively, with 31 different species identified. Aspergillus was the most predominant genus with five different species: Aspergillus niger (9.9%), terreus (4.4%), flavus (3.3%), fumigatus (8.8%) and versicolor (2.20%) isolated. Twenty-five and 18 species of fungi were identified in the low and high-risk units, respectively. The labour ward (n = 46; 25.8%) and modular theatre (n = 47; 42.3%) were the most contaminated units. Cladosporium spp. and Paecilomyces spp. were the most frequently isolated fungi in the low and high-risk units, respectively. The dialysis centre (n = 9; 8.1%) and renal transplant theatre (n = 7; 6.31%) had the lowest contamination rates in the high-risk units. Aspergillus niger, Cephalosporium curtipes, Penicillium chrysogenum and Penicillium glabrum were each identified in 4/6 units from which swabs were taken. The facility had no documented protocol for its water safety and quality. Our data reveal a high rate of contamination of hospital water sources by fungi, some of which are known to cause life-threatening infections. For better water treatment and water tank cleaning and disinfection, a standard protocol is advised. Ensuring that the water distribution systems in hospital settings are free of fungal contaminants is important to prevent the possibility of waterborne mycosis outbreaks.

Atypical Mycobacterial Infection in Post Abdomino-Thoracic Trauma: A Case Report

Objective/Background: SSIs remain a significant cause of morbidity and mortality after surgery. One in eight patients develop SSI after exploratory laparotomies making it one of the major factors responsible for post-operative mortality and morbidity. Atypical mycobacteria are responsible for a spectrum of diseases ranging from superficial skin infections to widely disseminated systemic infections. Health care associated infections due to non-tuberculous mycobacteria is on the rise due to contaminated hospital water supplies, solutions, improperly sterilized instruments and devices. Our case is of an atypical mycobacterial infection in a patient with abdomino-thoracic trauma who underwent multiple surgeries. Case presentation: A 24 year old gentleman presented with a penetrating stab injury to the abdomen and left hemi-thorax following an assault. Patient underwent an emergency exploratory laparotomy which revealed a 4 x 4 cm defect in the left hemi-diaphragm, through which the stomach was herniating into the left thoracic cavity. During the 2nd post-operative week, patient developed empyema thorax, for which pigtail drain was placed initially and later thoracotomy with decortication and intercostal drainage were performed. Following discharge after 2 weeks, he presented with fever, body pain and pus discharge from the previously inserted intercostal drain site. Pus obtained was positive for acid fast bacilli and gene expert was negative. Atypical mycobacterial infection was diagnosed based on high index of suspicion and he received treatment for 6 months. Conclusion: This case highlights that identification of atypical mycobacterial infections in post-operative patients require a high index of suspicion. Management requires multi-drug approach and surgical intervention wherever necessary. Even with the existing sterilization techniques and preventive measure, atypical mycobacterial infection cannot be completely eliminated from a hospital set-up and hence must be considered in all nosocomial infections.

Microbial profile and antibiotic resistance pattern of water supply in a tertiary care hospital of Uttarakhand.

In healthcare settings, hospital water and water-related devices can act as a reservoir for waterborne infections. Potable water, sinks, faucet aerators, showers, tub immersion, toilets, dialysis water, water baths, eyewash stations, and dental-unit water stations have all been linked to nosocomial outbreaks. This study aimed to determine the microbial profile and pattern of antibiotic resistance in the water supply of a tertiary care hospital in Uttarakhand. This is a 1-year prospective study which was carried out by the Department of Microbiology and Immunology at Sri Mahant Indersh Hospital (SMIH), Dehradun. A total of 154 water samples were collected from the AC outlets, ventilators in the Intensive care unit (ICUs), Operation theatre (OTs), and High dependency unit (HDUs), scrub stations, pantry, and blood bank, patient's bathroom, private ward, septic ward, labour room, transplant unit, laboratory, scope rinse water, the dialysis unit and tank throughout the hospital, including tap water (pre and post flush [25%]), tap swabs (24%), drinking water (9%), AC outlets (13%), and other areas (3%). 30 of the 154 (19.5%) water samples tested were culture-positive. The most contaminated water samples were tap swabs (27%, n = 8/30). A total of nine organisms were isolated, of which the most predominant was Pseudomonas aeruginosa (40%; 12/30), followed by Legionella pneumophila (13%; 4/30), Acinetobacter baumanii (10%; 3/30), Klebsiella pneumoniae (10%; 3/30), Escherichia coli (7%; 2/30), Enterococcus faecalis (7%; 2/30), Aspergillus flavus (7%; 2/30), Stenotrophomonas (3%; 1/30), and Fusarium spp. (3%; 1/30). Gram-negative bacilli and non-lactose fermenting (GNB and NLF) showed a high rate of contamination, 53.3% (n = 16/30). P. aeruginosa showed resistance to gentamicin and amikacin (42%), imipenem (50%), levofloxacin (58%), and colistin (25%), while Acinetobacter baumanii showed resistance to gentamicin and amikacin (67%), minocycline (63%), and levofloxacin, imipenem and colistin (33%). The study's findings show that a variety of microorganisms are contaminating hospital water supplies and can be a source of hospital-acquired infections. A suitable and robust surveillance program for hospital water supplies, as well as strict adherence to infection control practices, is strongly advised.

Sphingobacterium multivorum Meningitis in an Immunocompetent Patient with Pituitary Macroadenoma Apoplexy: A Case Report and Review of the Literature

Sphingobacterium multivorum is a Gram-negative bacterium previously classified as a Flavibacterium. It produces non lactose fermenting colonies and is capable of producing oxidase and catalase enzymes. It is found ubiquitously in the environment and has been isolated from food, plants, soil, and aquatic environments, including hospital water supplies. Only a few cases of clinical infections caused by Sphingobacterium multivorum have been reported. Most cases of infection have been demonstrated in immunosuppressed patients. This case report presents the case of a 23-year-old immunocompetent woman with pituitary macroadenoma haemorrhage who developed Sphingobacterium meningitis following neurosurgery and subsequently died from cardiac arrest.

Misidentification as Pseudomonas aeruginosa in hospital water supply samples

Drinking water in hospitals is often tested for Pseudomonas aeruginosa because of its virulence potential. This article describes a case where, based on EN ISO 16266, seven of 11 (64%) samples taken simultaneously from the drinking water system at a single hospital tested positive for P.aeruginosa. This resulted in extensive investigations and interventions, and a number of measures were implemented. However, supplementary analyses with more discriminatory power (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, 16S-rRNA sequencing) ruled out P.aeruginosa completely. The authors wish to raise awareness of this problem, and suggest that diagnostic uncertainty of results obtained by EN ISO 16266 should be indicated on laboratory reports. Wrongly assuming the presence of P.aeruginosa in hospital water supply systems can lead to unnecessary control measures, as analytical uncertainty massively influences the health risk assessment and the remediation measures initiated in medical environments.

Isolation of nontuberculous mycobacteria species from different water sources: a study of six hospitals in Tehran, Iran

PurposeNontuberculous mycobacteria (NTM) are ubiquitous bacteria that are naturally resistant to disinfectants and antibiotics and can colonize systems for supplying drinking water. Therefore, this study aimed to evaluate the prevalence of NTM in the drinking water of six hospitals in Tehran, Iran.MethodsTotally, 198 water samples were collected. Each water sample was filtered via a membrane filter with a pore size of 0.45 µm and then decontaminated by 0.005% cetylpyridinium chloride. The membrane filters were incubated on two Lowenstein-Jensen media at 25 °C and 37 °C for 8 weeks. The positive cultures were identified with phenotypic tests, and then NTM species were detected according to the hsp65, rpoB, and 16S rDNA genes. Drug susceptibility testing (DST) was also carried out.ResultsOverall, 76 (40.4%) of the isolates were slowly growing mycobacteria (SGM) and 112 (59.6%) of the ones were rapidly growing mycobacteria (RGM). The most common NTM were Mycobacterium aurum, M. gordonae, M. phocaicum, M. mucogenicum, M. kansasii, M. simiae, M. gadium, M. lentiflavum, M. fortuitum, and M. porcinum. Among these 188 samples, NTM ranged from 1 to > 300 colony-forming unit (CFU) /500 mL, with a median of 182 CFU/500 mL. In the infectious department of all hospitals, the amount of CFU was higher than in other parts of the hospitals. The DST findings in this study indicated the diversity of resistance to different drugs. Among RGM, M. mucogenicum was the most susceptible isolate; however, M. fortuitum showed a different resistance pattern. Also, among SGM isolates, M. kansasii and M. simiae, the diversity of DST indicated.ConclusionsThe current study showed NTM strains could be an important component of hospital water supplies and a possible source of nosocomial infections according to the CFU reported in this study. The obtained findings also help clarify the dynamics of NTM variety and distribution in the water systems of hospitals in the research area.

An Efficient No-Shutdown Pipe-Fixing Freezing Design for Water Management System in Hospitals during COVID-19: A Case Study

Ensuring the uninterrupted flow of the complex piped water distribution networks to combat the COVID-19 pandemic in Taiwan’s hospitals has become a priority. The process involved in the no-shutdown pipe fixing freezing method depends on the water supply system design and the conditions of the environment. Before carrying out repair works onsite, two experiments were undertaken to estimate the liquid nitrogen supply rate and make sure of its adequacy in relation to the fixing system’s heat transfer performance. Using an iron exhaust pipe and galvanized steel inlet pipe with jacket for a 50-mm-diameter water pipe, temperature variations and timelapse were recorded and analyzed. The results showed that the frost length on the water pipe surface at either side of the jacket was 1.2–1.8 times of the pipe diameter. The ice length (~45 cm) was longer than the jacket (~34 cm), and the water pressure at the jacket inlet side was 1 kg/cm2 greater than at the exit. Injecting the right amount of liquid nitrogen into the inlet and at a proper speed between 0.7 and 0.8 kg/min will ensure a safe and smooth completion of the ice plug formation process. The design and processes have been used successfully in hospital water supply system fixing works.

Investigation of two cases of Mycobacterium chelonae infection in haemato-oncology patients using whole-genome sequencing and a potential link to the hospital water supply

Haemato-oncology patients are at increased risk of infection from atypical mycobacteria such as Mycobacterium chelonae which are commonly found in both domestic and hospital water systems. To describe the investigation and control measures following two patient cases of M.chelonae and positive water samples in the study hospital. Water testing was undertaken from outlets, storage tanks and mains supply. Whole-genome sequencing (WGS) was used to compare patient and positive water samples. The subsequent infection control measures implemented are described. The WGS results showed two main populations of M.chelonae within the group of sampled isolates. The results showed that the patient strains were unrelated to each other, but that the isolate from one patient was closely related to environmental samples from water outlets, supporting nosocomial acquisition. WGS was used to investigate two patient cases of M.chelonae and positive water samples from a hospital water supply. Relevant control measures and the potential for chemical dosing of water systems to enhance proliferation of atypical mycobacteria are discussed.

Investigation of Legionella Pneumophila bacteria in hospital water supply systems

Investigation of Legionella Pneumophila bacteria in hospital water supply systems

The contamination of hospital water supply systems by <i>Legionella pneumophila</i>

The risk of severe infectious complications associated with provision of medical care continues to be a pressing issue in modern surgery. Legionella pneumophila, characterized by its wide distribution in water supply systems and is highly active in film formation, represents a dangerous/important cause of hospital-acquired pneumonia. Patients requiring immunosuppression, including organ transplant recipients, are in the special risk group. Prevention of hospital-acquired legionellosis in patients at risk is essential due to severe clinical manifestations and high mortality. Objective: to summarize the practical experience in detecting contamination of water supply systems by Legionella pneumophila strains in multidisciplinary hospitals in Moscow. Materials and methods. Isolation of Legionella pneumophila strains from water and biofilms of water supply systems in multidisciplinary hospitals in Moscow and serotyping of this pathogen using bacteriological, molecular genetic and enzyme immunoassay methods. Results. Legionella pneumophila content in water reached high levels. The peculiarities of Legionella pneumophila contamination of hot water supply systems included formation of stable biofilms, in which other hospital-acquired pathogens were also identified. The share of Legionella pneumophila «SG 1», which causes up to 80% legionellosis cases in the world, was 13% in the water of the hospitals surveyed. The most effective measures for prevention of legionellosis are actions aimed at ensuring water biosecurity. Conclusion. There are potential risks of disease in the surgical wards of hospitals providing medical care, including in immunocompromised patients. Due to potential risks, prevention of hospital-acquired legionellosis is a necessary component of ensuring the safety of treatment for immunosuppressed patients.

Legionella spp. in Polish hospitals in 2009–2013 and 2014–2016: An epidemiological analysis

Summary Introduction Bacteria of the genus Legionella cause Legionnaires’ disease (atypical pneumonia, often with a severe clinical course) and Pontiac fever (self-limiting infection with flu-like symptoms). Legionella spp. are commonly found in natural aquatic environments and artificial water distribution systems. Material & Methods An epidemiological analysis of Legionella spp. in hospital water supply systems was based on the results obtained from Sanitary-Epidemiological Stations of Poland. The materials for this study were hot water samples collected from 346 hospitals in 2009–2013 and from 221 hospitals in 2014–2016. Results Between 2014 and 2016, there was a decrease in the percentage of the number of water samples in Group A (<100 CFU/100 ml). In other groups: B (>100 CFU/100 ml), C (>1000 CFU/100 ml), D (>10 000 CFU/100 ml) was observed an increase in the percentage of the number of water samples, which was a negative phenomenon. The mean number of L. pneumophila colonies in analyzed periods 2009–2013 and 2014–2016 were different. In 2009–2013, the most virulent L. pneumophila serogroup 1 (SG 1) was detected in 3 hospitals (0.9%), and L. pneumophila SG 2-14 were isolated in 20 (5.5%). Between 2014 and 2016, L. pneumophila SG 1 and L. pneumophila SG 2-14 were found in 5 hospitals (2.2%) and 18 hospitals (8.1%), respectively. Disscusion In this study a comparative epidemiological analysis was performed on the prevalence of L. pneumophila in hospital water supply systems in Poland in the following two periods: 2009 –2013 and 2014–2016. The study demonstrated that the water supply systems of Polish hospitals were colonized by L. pneumophila at different levels. However, between 2014 and 2016 an upward trend was observed in comparison with 2009–2013.

Unmanned Aerial Vehicles in Modern Power Systems: Technologies, Use Cases, Outlooks, and Challenges

The electricity network is a very large-scale and widely distributed system that is highly interdependent with other large infrastructure systems (e.g., natural gas, telecommunication, water and wastewater, and transportation). Power grids are being stressed by severe loading conditions caused by the rising electrification of infrastructure (e.g., in creasing the use of electric vehicles) as well as the overall growth in world population and electricity usage. Any prolonged electricity interruptions can have a widespread effect on other systems, including disruptions in Internet and security equipment, traffic and street lights, pumping stations and public transportation, home appliances and tall building elevators, large industrial equipment and hospital devices, water supplies and natural gas delivery networks, and so on.

Ten-Year Retrospective Analysis of Legionella Diffusion in Hospital Water Systems and Its Serogroup Seasonal Variation.

Legionella spp. are ubiquitous aquatic organisms found to be associated with community-acquired pneumoniae (CAP) as well as hospital-acquired pneumonia (HAP). Direct inhalation of aerosols from environmental colonisation is typically the source of infection. The aim of this study was to determine the level of colonisation in hospital water supply systems in order to assess the criticality of the water distribution network and strengthen preventive measures. From 2009 to 2018, 769 water samples were collected and then analysed according to the standard methods indicated in ISO11731-2:2004 and ISO11731:2017 for Legionella detection. The samples were positive in 37.1% cases (n. 285) and negative in 62.9% cases (n. 484). The threshold of 10,000CFU/L was exceeded in 15.1% cases and led to decolonisation as indicated by Italian and European ECDC guidelines. In the autumn-winter period SG1 showed a positivity of 41.2% (n. 40) with a decrease in the spring-summer period with 9.6% (n. 18) of positivity. In contrast, SG2-15 showed a positivity of 30.9% (n. 30) in autumn-winter, which tends to increase to 56.9% (n. 112) in spring-summer (p<0.001). Surprisingly, besides showing a seasonal trend already described previously in the literature, the positivity of our sample was not balanced even for serogroups in the two periods. This could be due to genetic differences and ecological niches to be further investigated that could also have links with the greater pathogenicity of SG1. Environmental microbiological surveillance and risk assessment should be performed more frequently and disinfection must be carried out, especially in health facilities where people are more susceptible to infections.

Pseudo-outbreak of Mycobacterium fortuitum in a hospital bronchoscopy unit

Mycobacterium fortuitum survive in different environmental conditions, biofilm formation and resistance to chlorinated disinfectants makes its isolation frequent in hospital environments, even being involved in outbreaks by contamination of medical equipment such as bronchoscopes. We describe a pseudo-outbreak by M fortuitum isolated in samples from 9 patients who underwent bronchoscopy in the pneumology bronchoscopy unit of the University Hospital Complex of the Canary Islands from December 2016 to March 2017. We proceeded to investigate the pseudo-outbreak with a combination of epidemiologic, environmental, and molecular typing data. The source/reservoir of pseudo-outbreak was the hospital water used by the bronchoscope automatic washing machine (without antibacterial filter), so control measures were taken. Molecular typing was performed on 7 strains from 7 patients, and a sample of water was collected from a tap in the pneumology bronchoscopy unit: all of which had the same pattern. Our study demonstrates the presence of nontuberculous mycobacteria in the hospital water supply, and thus the need to take measures against them because they compromise patients' health. We also suggest the need for hospital water quality guidelines in which methods to control and/or eliminate them are established.

Pseudo-outbreak of Mycobacterium paragordonae in a hospital: possible role of the aerator/rectifier connected to the faucet of the water supply system

Pseudo-outbreaks of non-tuberculous mycobacteria (NTM) in association with the water supply system in hospitals have been previously reported. We found that the frequency of NTM isolation in clinical samples increased after the reconstruction and renovation of a hospital in Japan in 2014. To analyse NTM, their possible relationship with the hospital water supply system, and outcomes of preventive measures. Environmental samples obtained from the water supply in hospital wards were tested for NTM. On obtaining positive results, the bacteria were further analysed using polymerase chain reaction (PCR). The PCR products of NTM showed that most samples tested positive for Mycobacterium paragordonae. Because none of the analysed patients developed any disease due to these bacteria, this event was considered a pseudo-outbreak. Investigation of the water supply system revealed that samples obtained from the recently attached aerators/rectifiers during hospital renovation tested positive for these bacteria. Therefore, measures to remove aerators/rectifiers and prevent patients from drinking tap water in the hospital were introduced. Thereafter, the frequency of NTM-positive samples significantly decreased in the hospital. This study is one of the few reports which reveal the possibility of pseudo-outbreaks of M.paragordonae in hospitals, hence raising the question whether aerators/rectifiers should be used in hospitals at all, because their mesh structure may promote NTM proliferation in supplied water. The importance of surveillance of bacteria derived from the environment, particularly after hospital reconstruction/renovation, is re-emphasized.

Cluster endophthalmitis due to Stenotrophomonas maltophilia following intravitreal bevacizumab: outcomes of patients from North India

PurposeTo study features, management and outcomes of cluster endophthalmitis following intravitreal bevacizumab (BCZ) injection in North India.MethodsIn this retrospective study, 28 patients (23 men) (mean age of 59.07±13 years) who...

Case report of isolation of Mycobacterium setense from a hospital water supply

Objective: The current study is a report of isolation and identification of Mycobacterium setense from a tap running water in a general surgery ward in a hospital in Isfahan, Iran. Materials and Methods: This bacterium was obtained from a hospital water sample according to the cetylpyridinium chloride 0.005% method on Lowenstein–Jensen slant and characterized to the species level as M. setense using results of phenotypic test and 16S rRNA sequencing. Results: This isolate identified to the species level using the conventional and molecular method as M. setense, this bacterium has highest similarity (100%) with those of M. setense CIP109395 16S rRNA gene sequences. Conclusion: This study can be useful and provide important information for learning about the natural habitats of pathogenic species of nontuberculosis mycobacteria. Furthermore, the molecular tests such as 16S rRNA gene sequencing can be applied for reliable and appropriate identification of mycobacterial species.

Environmental surveillance of Legionella pneumophila in distal water supplies of a hospital for early identification & prevention of hospital-acquired legionellosis.

Background & objectives:Legionella pneumophila, a ubiquitous aquatic organism is found to be associated with the development of the community as well as hospital-acquired pneumonia. Diagnosing Legionella infection is difficult unless supplemented with, diagnostic laboratory testing and established evidence for its presence in the hospital environment. Hence, the present study was undertaken to screen the hospital water supplies for the presence of L. pneumophila to show its presence in the hospital environment further facilitating early diagnosis and prevention of hospital-acquired legionellosis.Methods:Water samples and swabs from the inner side of the same water taps were collected from 30 distal water outlets present in patient care areas of a tertiary care hospital. The filtrate obtained from water samples as well as swabs were inoculated directly and after acid buffer treatment on plain and selective (with polymyxin B, cycloheximide and vancomycin) buffered charcoal yeast extract medium. The colonies grown were identified using standard methods and confirmed for L. pneumophila by latex agglutination test.Results:About 6.66 per cent (2/30) distal water outlets sampled were found to be contaminated with L. pneumophila serotype 2-15. Isolation was better with swabs compared to water samples.Interpretation & conclusions:The study showed the presence of L. pneumophila colonization of hospital water outlets at low levels. Periodic water sampling and active clinical surveillance in positive areas may be done to substantiate the evidence, to confirm or reject its role as a potential nosocomial pathogen in hospital environment.

Waterborne Pseudomonas aeruginosa transmission in a hematology unit?

Pseudomonas aeruginosa is an important nosocomial pathogen that commonly colonizes hospital water supplies, including in taps and sinks. We report the transmission of P. aeruginosa from water to patients in a clinical hematology setting. P. aeruginosa from water samples were compared to clinical isolates from hematology ward patients, via molecular typing (pulsed field gel electrophoresis). P. aeruginosa cultured from blood cultures from 3 patients was indistinguishable from water strains, by molecular typing. Based on infection control inspections, the transmission event was surmised to be due to cleaning of equipment, specifically an infusion therapy procedure tray used to transport intravenous drugs to patients, with water from an outlet colonized by P. aeruginosa. We show the importance of holistic factors, such as disposal of patient waste water, cleaning of tap outlets, and cleaning of medical equipment, in the transmission of P. aeruginosa, and demonstrate that the role of waterborne transmission of this organism in a hematology setting cannot be overlooked. We suggest that appropriate management of water, including both holistic and engineering interventions, is needed to stop transmission of P. aeruginosa from water to patients.