Contamination Of Hospital Environment Research Articles

Aptasensor for the detection of Methicillin resistant Staphylococcus aureus on contaminated surfaces

There is mounting evidence that contaminated hospital environment plays a crucial role in the transmission of nosocomial pathogens such as MRSA. The institution of infection control protocols is predicated on the early laboratory detection of the pathogen from relevant samples.Processing of environmental samples for the presence of bacterial contaminants in the clinical environment is poorly standardized when compared with analysis of clinical samples. The various laboratory methods available for processing environmental samples are difficult to standardized and most require a long turnaround time before results are available.In this study, we present a report of the performance of a novel pathogen aptasensor swab designed to qualitatively and quantitatively detect MRSA, on contaminated non-absorbable surfaces. The visual detection limit of the MRSA aptasensor swab was less than 100 CFU/ml and theoretically using a standard curve, was 2 CFU/ml. A relatively short turnaround time of 5 min was established for the assay while the linear range of quantitation was 102–105 CFU/ml. Engineered aptasensor targets MRSA selectively and binds to none of the other tested bacterial pathogen, on a multi-contaminated surface. This novel detection tool was easy to use and relatively cheap to produce.

Hospital environmental contamination and colonization of hospitalized peripartum women and neonates with antimicrobial resistance genes

Background: Contamination of the hospital environment with pathogens carrying antimicrobial resistance (AMR) genes may contribute to transmission. Inadequate environmental cleaning and poor hand hygiene compliance may transfer AMR pathogens resulting in colonization and/or infection. Methods and materials: A cross-sectional study was conducted in the obstetric and neonatal wards at Tygerberg Hospital in Cape Town, South Africa between February and December 2016. To establish the density of hospital environmental contamination, we sampled 378 high- and low-touch surfaces for the presence of the following resistance genes: CTX-M15, NDM, OXA-48 and KPC. We screened 180 peripartum women and 92 hospitalized neonates to establish the prevalence of patients’ rectal colonization with bacteria carrying AMR genes. The adequacy of environmental cleaning and hand hygiene compliance rates in the neonatal and obstetric wards was assessed using a validated Infection Control Assessment Tool. Univariate analysis models were built to identify associations between environmental contamination and patients’ colonization. Results: Overall prevalence of environmental contamination with AMR genes was 5.8% (22/378) including 19 (86.4%) samples with CTX-M15 and 3 (13.6%) with OXA-48. Low-touch surfaces had significantly higher levels of contamination with CTX-M15 than high-touch surfaces (8/72 [11.1%] versus 11/306 [3.6%]; p = 0.002). The environmental cleaning score was similar in neonatal (80%) and obstetric (81%) wards; the mean hand hygiene compliance rates were 63% and 50% in neonatal and obstetric wards respectively. Five percent (14/272 patients) had CTX-M15 rectal colonization, with higher rates among neonates than peripartum women (9/92 [9.8%] vs. 5/180 [2.8%]; p = 0.013). CTX-M15 hospital environment contamination was not a predictor of patients’ CTX-M15 colonization status [positive swab versus negative OR = 1.8 (95% CI 0.2–22), p = 0.6. Conclusion: Levels of hospital environmental contamination with AMR genes were low (5.8%), and did not support a link between hospital contamination and maternal colonization with CTX-M15.

A Nosocomial Cluster of Roseomonas mucosa Bacteremia Possibly Linked to Contaminated Hospital Environment

Background: The genus Roseomonas, containing pink-pigmented glucose nonfermentative bacteria, has been associated with various primary and nosocomial human infections; however, to our knowledge, its nosocomial transmission has never been reported in the literature. Here, we report a nosocomial cluster of Roseomonas mucosa bacteremia. Methods: Two cases of R. mucosa bacteremia in 2018 are described. Clinical and epidemiological investigations were undertaken. Environmental surfaces prone to water contamination in the patient wards were sampled and cultured. The sampled surfaces included sinks, faucets, toilets, sewage, showerheads, refrigerators, exhaust vents, and washing machines. The 2 clinical isolates and all environmental isolates that showed growth of pink colonies were identified using matrix-assisted laser desorption/ionization time of flight mass spectrometry and 16S rRNA gene sequencing. Pulse-field gel electrophoresis (PFGE) was performed and fingerprinting software was used to analyze the DNA restriction patterns and determine their similarity. Results: Two patients who developed R. mucosa bacteremia had received care from the same treatment team. The patients were on different wards but had overlapping hospital stays. In addition to the treatment team, no other shared exposure was identified. Moreover, 126 environmental surfaces were sampled, of which 7 samples grew pink colonies. The 9 isolates from the patients and the environmental samples were examined using 16S rRNA gene sequencing. Overall, 7 isolates, including isolates from both patients, were identified as R. mucosa, and the other 2 isolates were identified as Roseomonas gilardii subsp. rosea (Fig. 1). With 80% similarity as a cutoff, PFGE analysis revealed that the R. mucosa isolates from 2 patients’ blood cultures and 3 environmental isolates (a washing machine in the ward, a sink in the shared washroom, and a sink in the patient room) belonged to the same clone (Fig. 2). Conclusions: The hospital water environment was contaminated with R. mucosa, and the same clone caused bacteremia in 2 separate patients, suggesting nosocomial transmission of R. mucosa possibly linked to contaminated water, environment, and/or patient care.Funding: NoneDisclosures: None

Environmental contamination of SARS-CoV-2 in healthcare premises

ObjectivesA large number of healthcare workers (HCWs) were infected by SARS-CoV-2 during the ongoing outbreak of COVID-19 in Wuhan, China. Hospitals are significant epicenters for the human-to-human transmission of the SARS-CoV-2 for HCWs, patients, and visitors. No data has been reported on the details of hospital environmental contamination status in the epicenter of Wuhan. MethodsWe collected 626 surface swabs within the Zhongnan Medical Center in Wuhan in the mist of the COVID-19 outbreak between February 7 - February 27, 2020. Dacron swabs were aseptically collected from the surfaces of 13 hospital function zones, five major objects, and three major PPE. The SARS-CoV-2 RNAs were detected by reverse transcription-PCR. ResultsThe most contaminated zones were the intensive care unit specialized for taking care of novel coronavirus pneumonia (NCP) (31.9%), Obstetric Isolation Ward specialized for pregnant women with NCP (28.1%), and Isolation Ward for NCP (19.6%). We classified the 13 zones into four contamination levels. The most contaminated objects were self-service printers (20.0%), desktop/keyboard (16.8%), and doorknob (16.0%). Both hand sanitizer dispensers (20.3%) and gloves (15.4%) were the most contaminated PPE. ConclusionOur findings emphasize the urgent need to ensure adequate environmental cleaning, strengthen infection prevention training, and improve infection prevention among HCWs during the outbreak of COVID-19.

Role of Clostridioides difficile in hospital environment and healthcare workers

Clostridioides difficile infection (CDI) was traditionally considered to be transmitted within healthcare environment, from other patients or healthcare workers (HCW). Recently, this idea has been challenged. Our objective was to determine the extent of C. difficile contamination in hospital environment with a simplified method for C. difficile recovery. Environmental samples were taken from rooms of patients positive for CDI (Case) and negative for toxigenic C. difficile (Control). Environmental sampling was performed at the time a fecal sample was taken for CDI diagnosis, 48 h after, and 10 days after. HCW hands were also sampled.A total of 476 environmental samples were collected, 246 samples from “Case” rooms and 230 from “Control”. Overall, 15.34% of environmental samples were positive for toxigenic C. difficile (TCD), 20.72% of “Case” rooms samples and 9.57% of the samples from “Control” rooms (p = 0.001). When samples from “Case” rooms were analyzed by sampling time, at diagnosis 52.94% were positive, 38.46% were positive at 48 h after symptom resolution and 23.07% were positive after course of treatment. Overall, the most contaminated site corresponded to the bathroom tap, followed by the toilet. We recovered TCD from alcohol-based dispensers and from 4.2% of HCW hands.We found a high proportion of surfaces contaminated with TCD, as well as hand colonization. Notably, even after isolation measures were terminated, there was still TCD contamination.

A nosocomial cluster of Roseomonas mucosa bacteremia possibly linked to contaminated hospital environment

Roseomonas, a genus of pink-pigmented glucose non-fermentative bacteria, has been associated with various primary and hospital-acquired human infections; however, to our knowledge, its nosocomial transmission has never been reported. Clinical and epidemiological investigations were carried out after two cases of R. mucosa bacteremia occurred in our hospital in 2018. Environmental samples were taken of environmental surfaces prone to water contamination in the wards and cultured. The two clinical isolates and all environmental isolates that showed growth of pink colonies were identified using matrix-assisted laser desorption/ionization time of flight mass spectrometry and 16S rRNA gene sequencing. Pulse-field gel electrophoresis (PFGE) was performed and fingerprinting software was used to analyze the DNA restriction patterns and determine their similarity. Two patients who developed R. mucosa bacteremia had received care from the same treatment team. Of 126 environmental samples, five showed growth of R. mucosa. Using 80% similarity as the cut-off, PFGE analysis revealed that the isolates from the two patients’ blood cultures and three environmental isolates belonged to the same clone. The hospital water environment was contaminated with the same clone of R. mucosa that caused bacteremia in the two patients, suggesting nosocomial transmission linked to contaminated environment. Increased vigilance is needed to monitor the emergence of Roseomonas in healthcare settings.

Identification and characterization of methicillin-resistant Staphylococcus spp. isolated from surfaces near patients in an intensive care unit of a hospital in southeastern Brazil.

INTRODUCTION: Contaminated hospital environments contribute to the transmission of microorganisms associated with healthcare. Contaminated surfaces handled by patients or healthcare professionals are a source of microorganism transmission by hand. Methicillin-resistant Staphylococcus bacteria are among the main agents responsible for increasing healthcare-associated infections in Brazil and worldwide. METHODS: The objective of this study was to screen and characterize methicillin-resistant Staphylococcus spp. on surfaces near patients in an intensive care unit. Microbiological samples, collected from ten beds in an intensive care unit with five sampling sites, were inoculated into a methicillin-resistant Staphylococcus aureus chromogenic medium. MALDI-TOF and PCR analyses were used to identify the bacteria. Antimicrobial susceptibility was determined using the disk diffusion test. The presence of the mecA gene was investigated using PCR. RESULTS: We observed that 44 out of the 50 sampling sites presented grown isolates in the methicillin-resistant Staphylococcus aureus medium. The incidence of isolated microorganisms on the right side rail, left side rail, tables, infusion pump keypad, and cardiac monitor were 18.8 %, 36.7 %, 10.9 %, 2.4 %, and 31 %, respectively. The 42 isolates included in this study were identified as coagulase-negative Staphylococcus. All of these microorganisms were multidrug-resistant and mecA gene-positive. CONCLUSIONS: This study identified the presence of methicillin-resistant coagulase-negative Staphylococcus on the beds of an intensive care unit, providing evidence for the necessity of assertive actions to decrease the risk of healthcare-associated infections at the site.

Risk Factors and Microbiological Control of Soils, Surfaces and Medical-technical Equipment at the Abomey-Calavi / So-Ava University Hospital Center, Benin

Aims: The aim of our work was, on the one hand, to evaluate the risk factors for infectious contamination in hospital environments and, on the other hand, to carry out a microbiological control of surfaces at the Abomey-Calavi / So-Ava hospital in Benin.
 Methodology: The risk factors were evaluated using structured interviews based on the questionnaire. Fifty-five health care workers were surveyed and the questionnaire focused on: i) knowledge of care-associated infections and risk factors, ii) services most affected by care-associated infections and iii) origin of care-associated infections. For the microbial quality control of medical surfaces and materials, samples were collected by the dry swab method and the microbial isolation was carried out on Chapman and EMB agar plates. The biochemical analyses were carried out for the confirmations.
 Results: Out of 55 respondents, the 93% think that bacterial germs are often involved in care-associated infections. In addition, 80% of respondents believe that the healthcare environment may be the source of care-associated infections. Regarding the microbiological quality of the surfaces, out of 96 samples collected, 77% were contaminated with Staphylococcus spp and 30% with Enterobacteria. Concerning units’ contamination, the highest prevalence was observed in paediatrics with 92% of samples contaminated with Staphylococcus spp followed by the operating theatre (87%).
 Conclusion: It is clear from our work that hygiene managers must carry out preventive and corrective actions for the respect of the principles of hygiene. It would also be important to conduct regular microbiological monitoring of surfaces to identify any contamination.

Molecular epidemiology of toxigenic Clostridioides difficile isolates from hospitalized patients and the hospital environment in Dhaka, Bangladesh

Epidemiology of Clostridioides difficile (syn. Clostridium difficile) infection (CDI) in Bangladesh is poorly understood. This study assessed the epidemiology of CDI in hospitalized patients and hospital environmental contamination of toxigenic C. difficile at two large urban Bangladesh hospitals. This 12-month prospective observational cohort study collected stool samples from adults with diarrhea and recent antimicrobial exposure during 2017. Environmental samples were collected by swabbing surfaces of hospital common areas. Samples underwent toxigenic culture. C. difficile isolates were tested for toxins A and B and PCR-ribotyped. Of 208 stool samples, 18 (8.7%) were positive for toxigenic C. difficile. Of 400 environmental samples, 45 (11%) were positive for toxigenic C. difficile. Ribotypes present in ≥10% of stool isolates were 017 (38%), 053–163 (13%), and a novel ribotype (FP435 [13%]). Common ribotypes in environmental isolates were 017 (22%), 053–163 (11%), 106 (24%). This is the first report describing current epidemiology of CDI in at risk hospitalized adult patients in Bangladesh.

Fighting AMR in the Healthcare Environment: Microbiome-Based Sanitation Approaches and Monitoring Tools.

Healthcare-associated infections (HAIs) affect up to 15% of all hospitalized patients, representing a global concern. Major causes include the persistent microbial contamination of hospital environment, and the growing antimicrobial-resistance (AMR) of HAI-associated microbes. The hospital environment represents in fact a reservoir of potential pathogens, continuously spread by healthcare personnel, visiting persons and hospitalized patients. The control of contamination has been so far addressed by the use of chemical-based sanitation procedures, which however have limitations, as testified by the persistence of contamination itself and by the growing AMR of hospital microbes. Here we review the results collected by a microbial-based sanitation system, inspired by the microbiome balance principles, in obtaining more effective control of microbial contamination and AMR. Whatever the sanitation system used, an important aspect of controlling AMR and HAIs relates to the ability to check any variation of a microbial population rapidly and effectively, thus effective monitoring procedures are also described.

471. Prevalence and Characteristics of Clostridioides difficile Infection in Bangladesh

BackgroundThe estimated prevalence of Clostridioides difficile infection (CDI) in several South Asian countries is 10.5%, similar to that in North America and Europe. However, the epidemiology of CDI in Bangladesh is unknown. We aimed to assess the prevalence of CDI and assess hospital environmental contamination of toxigenic C. difficile in Bangladesh.MethodsThis was a prospective observational cohort study at two large tertiary care centers in Dhaka, Bangladesh, conducted from January 2017 to December 2017. Stool samples were collected from hospitalized adults with diarrhea (≥3 loose stools in a 24-hour period) and antimicrobial exposure within the past 30 days. Hospital environmental samples were collected by swabbing surfaces of common areas in the hospital. All samples underwent toxigenic culture. C. difficile isolates were tested for toxins A and B and PCR-ribotyped.ResultsOf 204 stool samples collected, 16 (7.8%) were positive for toxigenic C. difficile. Patients with CDI shared a room with significantly more patients (Table 1). Of 392 environmental samples, 48 (12.2%) were positive for toxigenic C. difficile, which was more common in patient care vs. nonpatient care areas (14.4% vs. 7.8%, P = 0.057). Twelve clinical stool isolates and 42 environmental isolates were ribotyped. Ribotypes identified in stool isolates were F017 (50%), FP053-163 (17%), FP435 (17%), F106 (8%), and F014-020 (8%). With the exception of FP435, these were also the most common ribotypes in environmental isolates: F017 (24%), FP053-163 (12%), F106 (26%), and F014-020 (10%).ConclusionFor the first time, we report the prevalence of CDI and ribotypes in at risk patients in Bangladesh. Rates and ribotypes are similar to other resource-rich or resource-limited countries.Table 1: Demographic Data for All Stool SamplesVariableNo toxigenic C. difficile (n = 188)Toxigenic C. difficile (n = 16) P Female sex, n (%)77 (41)9 (56)0.234Age, years, median (IQR)46 (32–58)39 (25–53)0.212Hospital A, n (%)149 (79)13 (81)>0.99Length of prior hospital stay, days, median (IQR)13 (7–23)14 (8–32)0.798Duration of previous antibiotics, days, median (IQR)10 (7–17)12 (6–20)0.687Number of patients in the same room, median (IQR)13 (7–19)19 (14–20)0.009Disclosures K. W. Garey, Merck & Co.: Grant Investigator, Grant recipient.

Contamination of microbial pathogens and their antimicrobial pattern in operating theatres of peri-urban eastern Uganda: a cross-sectional study

BackgroundMicrobial contamination of hospital environment, especially in operating theatres (OT) and other specialized units has greatly contributed to continuous and multiple exposure to nosocomial infections by patients and the public.We purposed to assess microbial contamination of operating theatres and antibacterial sensitivity pattern of bacteria isolated from theatres of Mbale Regional Referral Hospital, Eastern Uganda.MethodsWe employed a laboratory based cross-sectional study design. Swabbing of different surfaces and settle plate establishment in 4 various operating theatres was carried out. A total of 109 samples were collected, 31 air samples and 78 swabs from four operating theatres. Samples were collected in the mornings after disinfection prior to start of daily operations. Antibacterial sensitivity testing of isolated bacterial pathogens was performed by Kirby Bauer disc diffusion method following standard operating procedure. Colony counts for the settle plates were carried out using a colony counter.ResultsAll the four theatres had their mean colony counts exceeding the acceptable limit of 5 cfu/dm2/h. Gynaecology theatre had up to 261 cfu/dm2/h and Ophthalmology operating theatre had approximately 43 cfu/dm2/h. A total of 14 different organisms were isolated with Pseudomonas spp. [23.9%]; Bacillus spp. [17.5%] and Aspergillus spp. [15.8%] being the most common contaminants respectively. Other isolates included Enterococcus spp., Rhizopus spp. and Coagulate Negative Staphylococcus isolates especially from settle plates. Most bacterial isolates showed considerable resistance to antibacterial agents. Pseudomonas spp. was resistant to chloramphenicol (53.6%) and cotrimoxazole (57.1%). Most of the bacterial pathogens were sensitive to imipenem [83.3%].ConclusionsThere is moderate contamination of operating theatres of Mbale Regional Referral Hospital. Common organisms were Pseudomonas, Bacillus, and Aspergillus spps. Resistance was observed against chloramphenicol and cotrimoxazole. More caution is necessary to carefully disinfect the operating theatres at Regional referral settings and similar tertiary health care centres with more emphasis on obstetrics and gynecology theatres. Diagnosis and care of patients at such clinical settings should consider the possibility of antibiotic resistance.

Risk factors for veterinary hospital environmental contamination with Salmonella enterica.

Healthcare-associated infections in veterinary hospitals are commonly attributed to Salmonella enterica, particularly in large animal facilities, and are characteristically associated with widespread environmental contamination. The objective of this study was to investigate factors influencing the likelihood of identifying environmental contamination of a veterinary hospital with S. enterica, while exploring different analytic methods to model complex factors that may influence this ecology. Environmental surveillance samples were collected in a large veterinary hospital as part of a long-term infection control programme. Data were collected retrospectively from the electronic medical records database. Many easily measured variables were complex in nature (i.e., they represented variance that is unmeasured or unidentified as a specific factor) necessitating the use of alternative analytic methods (variable cluster and principal components analyses) to provide perspective regarding the complex data structure and latent factors that may be contributing to this ecology. Subsequently, multivariable logistic regression was performed using generalised estimating equations. Results suggest the probability of detecting Salmonella in the environment increased as demand on personnel increased (e.g., in a busy hospital). Veterinary personnel need to remain vigilant in implementing practices that we believe empirically will mitigate risk for widespread environmental contamination and sustained transmission among patients (i.e., rigorous hygiene for personnel and the environment).

Wastewater and urine treatment by UVC-based advanced oxidation processes: Implications from the interactions of bacteria, viruses, and chemical contaminants

To mitigate the risk of environmental contamination by microorganisms and chemical pollutants, on-site hospital wastewater and urine treatments have been recently assessed as countermeasures. In this study, we evaluated the use of advanced oxidation processes (AOPs) as a post-biological treatment method against enteric microorganism surrogates (Escherichia coli and MS2 bacteriophage) in ultrapure water (MQ) and synthetic matrices (wastewater and urine). UVC, UVC/H2O2, and UV/Fenton methods have been evaluated in terms of disinfection kinetics, in the presence and absence of Iohexol, an iodinated contrast medium. The occurrence of MS2 or E. coli notably decreased the antagonist microorganism inactivation kinetics (i.e., E. coli or MS2, respectively), whereas the addition of H2O2 always improved the disinfection performance by 20–60%. When Iohexol was present, inactivation was considerably delayed in wastewater and urine, but not in MQ, which indicated a synergistic inactivation of E. coli and MS2 with Iohexol, up to instant inactivation. Despite the abrupt effects of Iohexol on disinfection, the re-growth/survival dynamics during 3–5 days after disinfection of wastewater and urine revealed high risk of bacterial re-growth, even from low leftover counts (10 CFU/mL) but not viral re-population. Finally, simulation of hospital wastewater treatment was conducted by treating actual primary and secondary wastewater, as well as fresh urine, spiked with Iohexol. This study achieved rapid bacterial and viral inactivation, even in the presence of high amounts of Iohexol, as found in hospital effluents. Our results indicate that these methods could be applied to highly contaminated hospital environments after proper optimization of exposure time, added H2O2, and Fe amounts.

Healthcare-acquired infections: prevention strategies.

Healthcare-acquired infections (HAI) impact on patient care and have cost implications for the Australian healthcare system. The management of HAI is exacerbated by rising rates of antimicrobial resistance (AMR). Health-care workers and a contaminated hospital environment are increasingly implicated in the transmission and persistence of multi-resistant organisms (MRO), as well as other pathogens, such as Clostridium difficile. This has resulted in a timely focus on a range of HAI prevention actions. Core components include antimicrobial stewardship, to reduce overuse and ensure evidence-based antimicrobial use; infection prevention strategies, to control MRO - particularly methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus spp. (VRE) and, more recently, multi-resistant Gram-negative bacteria; enhanced institutional investment in hand hygiene; hospital cleaning and disinfection; and the development of prescribing guidelines and standards of care. AMR surveillance and comparisons of prescribing are useful feedback activities once effectively communicated to end users. Successful implementation of these strategies requires cultural shifts at local hospital level and, to tackle the serious threat posed by AMR, greater co-ordination at a national level. HAI prevention needs to be multi-modal, requires broad healthcare collaboration, and the strong support and accountability of all medical staff.

Comparison of 16S ribosomal RNA gene sequence analysis and conventional culture in the environmental survey of a hospital

BackgroundNosocomial infection is one of the most common complications within health care facilities. Certain studies have reported outbreaks resulting from contaminated hospital environments. Although the identification of bacteria in the environment can readily be achieved using culturing methods, these methods detect live bacteria. Sequencing of the 16S ribosomal RNA (16S rRNA) gene is recognized to be effective for bacterial identification. In this study, we surveyed wards where drug-resistant bacteria had been isolated and compared conventional culture methods with 16S rRNA gene sequencing methods.MethodsSamples were collected using sterile swabs from two wards (northern and southern) at Gunma University Hospital contaminated by Acinetobacter sp.. We extracted DNA directly from the swabs. Following extraction, the DNA was amplified using polymerase chain reaction (PCR). The PCR products were cloned using the plasmid vector. The plasmid DNA were sequenced, and identification were performed using database. 16S rRNA gene sequence analyses were compared conventional culture methods.ResultsIn the northern ward, Acinetobacter sp. was detected from only two of 14 samples using the culture method. In contrast, 16S rRNA gene sequencing analysis detected Acinetobacter sp. from seven of 14 samples. Drug-resistant Acinetobacter sp. was isolated from bathrooms of the southern ward and was detected from four of seven samples using the culture method in comparison with six of seven samples by 16S rRNA gene sequencing analysis.ConclusionsMolecular biological analysis showed a higher sensitivity to detect specific bacteria and detected a greater number of species than the culture method. Our results suggest that 16S rRNA gene sequencing analysis is useful to identify range of contamination which were not found in conventional culture method. When a nosocomial outbreak cannot be adequately controlled, molecular biological analysis may serve as a useful tool for environmental surveys in hospitals.

Identificação de Staphylococcus epidermidis em formigas (Hymenoptera: Formicidae) coletadas em uma área de alimentação no município de Guarulhos, São Paulo

RESUMO: Com o processo de urbanização, ocorreu aumento da disseminação de doenças veiculadas por artrópodes, sendo os mais comuns as formigas. A presença delas é mais frequente pelo seu tamanho, por sua facilidade de locomoção e por sua forma de vida social. Assim, podem atuar como vetores mecânicos de bactérias endossimbiontes e patogênicas, ocasionando contaminação em alimentos e no ambiente hospitalar. Os objetivos deste artigo foram isolar e identificar bactérias contaminantes dos gêneros Escherichia sp., Staphylococcus sp. e Salmonella sp. em formigas operárias circulantes no entorno de uma lanchonete de intenso fluxo de pessoas. Foram coletados rastros de formigas no período vespertino, amostradas em quatro pontos do pátio no entorno da lanchonete. Após a coleta, as bactérias foram identificadas por cultivo em meio de cultura Caldo Triptona de Soja para enriquecimento e meios específicos. Dos quatro pontos coletados no entorno da lanchonete, dois apresentaram crescimento de Staphylococcus epidermidis. Este estudo identificou a presença de S. epidermidis em formigas operárias em uma lanchonete localizada em uma área de grande circulação de pessoas, indicando que elas podem ser vetores de contaminação em estabelecimentos de comércio de alimentos.

Bifunctional fluorescent benzimidazo[1,2-α]quinolines for Candida spp. biofilm detection and biocidal activity

Biofilms provide an ideal environment for protecting the microbial cells from damage caused by humoral and cellular immune system components, promoting resistance, infections and increasing mortality and morbidity of patients in health facilities. In an attempt to provide an innovative solution for preventing contamination in hospital environments, this study evaluated nine structural complementary fluorescent benzimidazo[1,2-α]quinolines as bifunctional agents that both detect and have biocidal activity against yeast biofilms on stainless steel surfaces. The benzimidazoles' staining capability was determined by a fluorescence microscopy study and spraying the substance on yeast biofilm contaminated stainless steel surfaces. Furthermore, their in vitro human leukocyte cytotoxicity was evaluated with trypan blue and their biocidal activity was determined as the minimum inhibitory concentration against Candida tropicalis, C. albicans and C. parapsilosis strains. Moreover, scanning electron micrographs were recorded to study the biocidal activity. This resulted in the identification of 7, which presents all the desired characteristics (such as solubility) and capabilities (staining and biocide activity against all tested biofilm forming yeast strains) at the same time. As such, benzimidazole 7 has the potential to guarantee the use of disinfected medical and surgical instruments in clinical and surgical procedures, consequently, contributing to an increased safety for patients.

Breath gas concentrations mirror exposure to sevoflurane and isopropyl alcohol in hospital environments in non-occupational conditions

Anaesthetic gases and disinfectants are a primary source of air contamination in hospitals. A highly sensitive sorbent-trap methodology has been used to analyse exhaled breath samples with detection limits in the pptv range, which allows volatile organic compounds (VOCs) to be detected at significantly lower levels (5–6 orders of magnitude below) than the recommended exposure limits by different organizations. Two common VOCs used in hospital environments, isopropyl alcohol (IPA) and sevoflurane, have been evaluated. Forced-expiratory breath samples were obtained from 100 volunteers (24 hospital staff, 45 hospital visitors and 31 external controls).Significant differences for IPA were found between samples from volunteers who had not been in contact with hospital environments (mean value of 8.032 ppbv) and people staying (20.981 ppbv, p = 0.0002) or working (19.457 ppbv, p = 0.000 09) in such an environment. Sevoflurane, an anaesthetic gas routinely used as an inhaled anaesthetic, was detected in all samples from volunteers in the hospital environment but not in volunteers who had not been in recent contact with a hospital environment. The levels of sevoflurane were significantly higher (p = 0.000 24) among staff members (0.522 ppbv) than among visitors to the hospital (0.196 ppbv). We conclude that highly sensitive methods are required to detect anaesthetic gas contamination in hospital environments.

A Lethal Case of Sphingomonas paucimobilis Bacteremia in an Immunocompromised Patient.

Sphingomonas paucimobilis is a yellow-pigmented, glucose nonfermenting, aerobic, Gram negative bacillus of low pathogenicity. This organism was found in the implantation of indwelling catheters, sterile intravenous fluid, or contaminated hospital environment such as tap and distilled water, nebulizer, ventilator, and hemodialysis device. A 55-year-old female was hospitalized for diabetic foot ulcer in the presence of multiple comorbidities: diabetes mellitus, colonic tuberculosis, end-stage renal disease, and indwelling catheters for central venous catheter and hemodialysis. The patient passed away on the 44th day of admission due to septic shock. The organism found on blood culture on the 29th day of admission was multidrug resistant S. paucimobilis. Severe infection and septic shock due to S. paucimobilis have been reported particularly in immunocompromised patients, but there has been only one reported case of death in a premature neonate with septic shock. This is the first reported lethal case of S. paucimobilis bacteremia in an adult patient.