Effectiveness of chlorhexidine in preventing infections among patients undergoing cardiac surgeries: a meta-analysis and systematic review.

BACKGROUND: Although several meta-analyses reported the impact of chlorhexidine (CHX) use in patients undergoing various types of surgery, no meta-analysis summarized the overall effectiveness of CHX specifically for cardiac surgery. This meta-analysis aimed to examine the impact of CHX on infections after cardiac surgery compared with other cleansers or antiseptics. METHODS: PubMed, Embase, and the Cochrane Library were searched from inception up to October 2020 for potentially eligible studies: (1) population: patients who underwent cardiac surgery; (2) intervention or exposure: any type of CHX use in the treatment or exposed group; (3) outcome: number of patients with infections; (4) comparison: placebo or other antiseptic agents; (5) English. The primary outcome was surgical site infection (SSI). RESULTS: Fourteen studies were included, with 8235 and 6901 patients in the CHX and control groups. CHX was not protective against SSI (OR = 0.77, 95% CI: 0.57-1.04, P = 0.090). CHX was protective for superficial wound infection (OR = 0.42, 95% CI: 0.26-0.70, P = 0.001), but not with deep wound infection (P = 0.509). CHX was not protective against urinary tract of infection (P = 0.415) but was protective for bloodstream infection (OR = 0.36, 95% CI: 0.16-0.80, P = 0.012), nosocomial infections (OR = 0.55, 95% CI: 0.44-0.69, P < 0.001), and pneumonia (OR = 0.26, 95% CI: 0.11-0.61, P = 0.002). CONCLUSIONS: In patients undergoing cardiac surgery, CHX does not protect against SSI, deep wound infection, and urinary tract infections but might protect against superficial SSI, bloodstream infection, nosocomial infections, and pneumonia.

Setting occupational exposure limits for antimicrobial agents: A case study based on a quaternary ammonium compound-based disinfectant.

Antimicrobial agents have become an essential tool in controlling the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and guidelines on their use have been issued by various public health agencies. Through its Emerging Viral Pathogen Guidance for Antimicrobial Pesticides, the US Environmental Protection Agency has approved numerous surface disinfectant products for use against SARS-CoV-2. Despite their widespread use and range of associated health hazards, the majority of active ingredients in antimicrobial products, such as surface disinfectants, lack established occupational exposure limits (OELs) to assist occupational health professionals in characterizing risks from exposures to these chemicals. Based on established approaches from various organizations, a framework for deriving OELs specific to antimicrobial agents was developed that relies on a weight-of-evidence evaluation of the available data. This framework involves (1) a screening-level toxicological assessment based on a review of the existing literature and recommendations, (2) identification of the critical adverse effect(s) and dose-response relationship(s), (3) identification of alternative health-based exposure limits (HBELs), (4) derivation of potential OELs based on identified points of departure and uncertainty factors and/or modification of existing alternative HBELs, and (5) selection of an appropriate OEL. To demonstrate the use of this framework, a case study is described for selection of an OEL for a disinfectant product containing quaternary ammonium compounds (quats). Three potential OELs were derived for this product based on irritation toxicity data, developmental and reproductive toxicity (DART) data, and modification of an existing HBEL. The final selected OEL for the quats-containing product was 0.1 mg/m3, derived from modification of an existing HBEL. This value represented the lowest resulting value of the three approaches, and thus, was considered protective of irritation and potential DART.

Assessing regulatory violations of disinfection by-products in water distribution networks using a non-compliance potential index.

Inactivating pathogens is essential to eradicate waterborne diseases. However, disinfection forms undesirable disinfection by-products (DBPs) in the presence of natural organic matter. Many regulations and guidelines exist to limit DBP exposure for eliminating possible health impacts such as bladder cancer, reproductive effects, and child development effects. In this paper, an index named non-compliance potential (NCP) index is proposed to evaluate regulatory violations by DBPs. The index can serve to evaluate water quality in distribution networks using the Bayesian Belief Network (BBN). BBN is a graphical model to represent contributing variables and their probabilistic relationships. Total trihalomethanes (TTHM), haloacetic acids (HAA5), and free residual chlorine (FRC) are selected as the variables to predict the NCP index. A methodology has been proposed to implement the index using either monitored data, empirical model results (e.g., multiple linear regression), and disinfectant kinetics through EPANET simulations. The index's usefulness is demonstrated through two case studies on municipal distribution systems using both full-scale monitoring and modeled data. The proposed approach can be implemented for data-sparse conditions, making it especially useful for smaller municipal drinking water systems.

Reducing viral contamination from finger pads: handwashing is more effective than alcohol-based hand disinfectants.

BACKGROUND: Hand hygiene is important for interrupting transmission of viruses through hands. Effectiveness of alcohol-based hand disinfectant has been shown for bacteria but their effectiveness in reducing transmission of viruses is ambiguous. AIM: To test efficacy of alcohol hand disinfectant against human enteric and respiratory viruses and to compare efficacy of an alcohol-based hand disinfectant and handwashing with soap and water against norovirus. METHODS: Efficacies of a propanol and an ethanol-based hand disinfectant against human enteric and respiratory viruses were tested in carrier tests. Efficacy of an alcohol-based hand disinfectant and handwashing with soap and water against noroviruses GI.4, GII.4, and MNV1 were tested using finger pad tests. FINDINGS: The alcohol-based hand disinfectant reduced the infectivity of rotavirus and influenza A virus completely within 30s whereas poliovirus Sabin 1, adenovirus type 5, parechovirus 1, and MNV1 infectivity were reduced <3 log10 within 3 min. MNV1 infectivity reduction by washing hands with soap and water for 30s (>3.0 ± 0.4 log10) was significantly higher than treating hands with alcohol (2.8 ± 1.5 log10). Washing with soap and water for 30s removed genomic copies of MNV1 (>5 log10), noroviruses GI.4 (>6 log10), and GII.4 (4 log10) completely from all finger pads. Treating hands with propanol-based hand disinfectant showed little or no reduction to complete reduction with mean genomic copy reduction of noroviruses GI.4, GII.4, and MNV1 being >2.6, >3.3, and >1.2 log10 polymerase chain reaction units respectively. CONCLUSIONS: Washing hands with soap and water is better than using alcohol-based hand disinfectants in removing noroviruses from hands.

Risk-assessment-based approach to patients exposed to endoscopes contaminated with Pseudomonas spp.

Patients exposed to bronchoscopes contaminated with Pseudomonas aeruginosa are at increased risk of pseudomonal infection. The optimal methods for management and mitigation of risk following exposure are controversial. This article describes a two-phase risk assessment following pseudomonal contamination of a family of 75 endoscopes, detected through routine surveillance and attributed to one endoscope washer-disinfector. An initial risk assessment identified 18 endoscopes as high risk, based on the presence of lumens used for irrigation or biopsy. Exposure was communicated to the patients' clinical teams and a further clinical risk assessment of the exposed patients was performed. No patients developed complications due to pseudomonal infection.

Predicting the disinfection efficiency range in chlorine contact tanks through a CFD-based approach.

In this study three-dimensional computational fluid dynamics (CFD) models, incorporating appropriately selected kinetic models, were developed to simulate the processes of chlorine decay, pathogen inactivation and the formation of potentially carcinogenic by-products in disinfection contact tanks (CTs). Currently, the performance of CT facilities largely relies on Hydraulic Efficiency Indicators (HEIs), extracted from experimentally derived Residence Time Distribution (RTD) curves. This approach has more recently been aided with the application of CFD models, which can be calibrated to predict accurately RTDs, enabling the assessment of disinfection facilities prior to their construction. However, as long as it depends on HEIs, the CT design process does not directly take into consideration the disinfection biochemistry which needs to be optimized. The main objective of this study is to address this issue by refining the modelling practices to simulate some reactive processes of interest, while acknowledging the uneven contact time stemming from the RTD curves. Initially, the hydraulic performances of seven CT design variations were reviewed through available experimental and computational data. In turn, the same design configurations were tested using numerical modelling techniques, featuring kinetic models that enable the quantification of disinfection operational parameters. Results highlight that the optimization of the hydrodynamic conditions facilitates a more uniform disinfectant contact time, which correspond to greater levels of pathogen inactivation and a more controlled by-product accumulation.

Radiation and ethylene oxide terminal sterilization experiences with drug eluting stent products.

Radiation and ethylene oxide terminal sterilization are the two most frequently used processes in the medical device industry to render product within the final sterile barrier package free from viable microorganisms. They are efficacious, safe, and efficient approaches to the manufacture of sterile product. Terminal sterilization is routinely applied to a wide variety of commodity healthcare products (drapes, gowns, etc.) and implantable medical devices (bare metal stents, heart valves, vessel closure devices, etc.) along with products used during implantation procedures (catheters, guidewires, etc.). Terminal sterilization is also routinely used for processing combination products where devices, drugs, and/or biologics are combined on a single product. High patient safety, robust standards, routine process controls, and low-cost manufacturing are appealing aspects of terminal sterilization. As the field of combination products continues to expand and evolve, opportunity exists to expand the application of terminal sterilization to new combination products. Material compatibility challenges must be overcome to realize these opportunities. This article introduces the reader to terminal sterilization concepts, technologies, and the related standards that span different industries (pharmaceutical, medical device, biopharmaceuticals, etc.) and provides guidance on the application of these technologies. Guidance and examples of the application of terminal sterilization are discussed using experiences with drug eluting stents and bioresorbable vascular restoration devices. The examples provide insight into selecting the sterilization method, developing the process around it, and finally qualifying/validating the product in preparation for regulatory approval and commercialization. Future activities, including new sterilization technologies, are briefly discussed.

[New guidelines for investigating and evaluating the virucidal activity of disinfectants].

The diversity of viruses that cause human infectious diseases and problems in culturing some of them, such as hepatitis A, B, and C viruses and HIV, necessitate a search for test viruses that are closely resistant to disinfectants. The early methodical documents and the new one "Guidelines for Investigating and Evaluating the Virucidal Activity of Disinfectants" (MY 3.5.2431-08) include poliovirus (vaccine strain) as one of the test viruses. Adenovirus and thermoresistant parvovirus are additionally incorporated in order to harmonize with EN 14476. At least a 4-log10 reduction in test virus titers is taken as a criterion for virucidal activity. The suspension method is recommended for investigations of virucidal activity. The M. P. Chumakov Institute of Poliomyelitis and Viral Encephalitides has proposed human hepatitis A virus to choose disinfectants that are effective for decontamination in hepatitis A and recommended a surrogate virus, namely duck hepatitis B virus, to determine the activity of disinfectants against human hepatitis B (according to the U. S. Environmental Protection Agency's guidelines). The list of test viruses contains human hepatitis C virus recommended by the D. I. Ivanovsky Research Institute of Virology. Along with the virus, the list also includes bovine viral diarrhea virus that is surrogate for human hepatitis C virus (according to the guidelines of the Society for Control of Viral Diseases and the Robert Koch-Institute, Germany). The optimal time for various objects to be decontaminated is specified when the efficacy of disinfectants is studied.

Norma técnia y guía para el uso de antisépticos, desinfectantes e higiene de manos / Technical standards and guidance for the use of antiseptics, disinfectants and hand hygiene

El Ministerio de Salud presenta el documento Guía Norma Técnia y Guía para el uso de Antisépticos, Desinfectantes e Higiene de Manos el cual es un instrumento útil para el personal de salud que labora en establecimientos proveedores de servicios de salud. Brinda información sobre diferentes aspectos y procesos que deben realizarse en dichos establecimientos para la prevención de infecciones nosocomiales, promoviendo el uso adecuado de materiales, equipos y otros insumos necesarios para garantizar el proceso de atención. También define estándares e indicadores de calidad para el monitoreo y seguimiento sobre el uso racional y correcto de los antisépticos y desinfectantes; así como la higiene de la manos, incorporando la descripción de métodos de desinfección, antisepsia y esterilización, iniciando asi un cambio de cultura para mejorar las prácticas en baneficio de los usuarios y promover el manejo eficiente de los recursos disponibles...

[Hygienic standards of chemicals for water sterilization in the swimming pools].

The authors proposed a concept of making the hygienic standards for water disinfectants in the swimming pools, by substantiating their allowable residual concentrations (ARC), as well as criteria for evaluating the effectiveness and safety of swimming pool water disinfectants: a ratio of ARC to the optimum bactericidal concentration (if the ratio is less than 1; the agent is not recommended for use); a ratio of the maximum noneffective concentration of a local irritant action to the optimal bactericidal concentration of a disinfectant (if the ratio is < or =5; the agent is not permitted for use); a specific activity (agents that can cause allergenic and carcinogenic effects, as well as a mutagenic effect revealed on mammals or man are not permitted for use); the content of impurities in the disinfectant (when the agent is used in the dose equivalent to 3-5 optimal bactericidal concentrations; the water levels of impurities should be not more than 0.5 of the maximum permissible concentration. In accordance with the proposed procedure, ARC of BioPAH (polyhexamethyleneguanidine hydrochloride) has been estimated to be 5 mg/l. However, the agent may not be permitted for use in the swimming pools as it contains hazardous impurities.

Assessment of disinfectants cleaning against bacterial biofilm of house hold water tanks.

UNLABELLED: The purpose of this study was to compare the efficacy, in terms of bacterial biofilm penetration and killing, of some chemical disinfectants against E. coli and P. aeruginosa. This study was undertaken to examine the efficacy of some disinfectants including sodium hypochlorite, povidine and tryad detergent against E. coli biofilms and the efficacy of sodium hypochlorite and tryad detergents against P. aeruginosa. Two species biofilm of E. coli and P. aeruginosa were grown by flowing a dilute tryptic soy broth medium over an inclined cement, polyethylene, fiberglass and galvanized steel slides, 2.25 x 2.25 cm2 for 15 days. Biofilm formation was evaluated by scanning electron microscopy (SEM) and standard plate counts procedures through selective media for both E. coli and P. aeruginosa. In addition, some disinfectants were selected through disk diffusion susceptibility test. The disinfectants which gave higher zone of inhibitions, were applied to remove of E. coli and P. aeruginosa biofilms from cement, fiberglass, polyethylene and galvanized steel slide surfaces. Results showed that all disinfectants tested gave high inhibition of biofilm adhesion to tank surfaces with some being significant. CONCLUSION: polyethylene and galvanized steel are strongly recommended as alternative drinking house holds water tanks in Saudi Arabia. The choice of disinfectants or cleaning agents along with optimum concentrations and the time of action is very important when destroying microbes. It is also important that resistance of microbes to some disinfectants and cleaning agents is take into consideration when planning the cleaning process.

Evaluation of two methods of determining the efficacies of two alcohol-based hand rubs for surgical hand antisepsis.

The antimicrobial efficacies of preparations for surgical hand antisepsis can be determined according to a European standard (prEN 12791 [EN]) and a U.S. standard (tentative final monograph for health care antiseptic drug products [TFM]). The U.S. method differs in the product application mode (hands and lower forearms, versus hands only in EN), the number of applications (11 over 5 days, versus a single application in EN), the sampling times (0, 3, and 6 h after application, versus 0 and 3 h in EN), the sampling methods (glove juice versus fingertip sampling in EN), and the outcome requirements (absolute bacterial reduction factor [RF], versus noninferiority to reference treatment in EN). We have studied the efficacies of two hand rubs according to both methods. One hand rub was based on 80% ethanol and applied for 2 min, and the other one was based on 45% propan-2-ol, 30% propan-1-ol, and 0.2% mecetronium etilsulfate and applied for 1.5 min. The ethanol-based hand rub was equally effective as the 3-min reference disinfection of prEN 12791 in both the immediate (RFs, 2.97 +/- 0.89 versus 2.92 +/- 1.03, respectively) and sustained (RFs, 2.20 +/- 1.07 versus 2.47 +/- 1.25, respectively) effects. According to TFM, the immediate effects were 2.99 log10 (day 1), 3.00 log10 (day 2), and 3.43 log10 (day 5), and bacterial counts were still below baseline after 6 h. The propanol-based hand rub was even more effective than the reference disinfection of prEN 12791 in both the immediate (RFs, 2.35 +/- 0.99 versus 1.86 +/- 0.87, respectively) and sustained (RFs, 2.17 +/- 1.00 versus 1.50 +/- 1.26, respectively) effects. According to TFM, the immediate effects were 2.82 log10 (day 1), 3.29 log10 (day 2), and 3.25 log10 (day 5), and bacterial counts were still below baseline after 6 h. Some formulations have been reported to meet the efficacy requirements of one of the methods but not those of the other. That is why we conclude that, despite our results, meeting the efficacy requirements of one test method does not allow the claim that the requirements of the other test method are also met.

Avaliação do efeito imediato e residual do sabão anti-séptico, do PVP-I degermante, do PVP-I tópico e da clorexidina na degermação das mãos / Evaluation of immediate and residual effect of liquid soap, degerming povidine-iodine, topic povodine-iodine and chlorhexidine on handwashing

O objetivo deste trabalho foi avaliar o efeito imediato e residual da água e do sabão bactericida, do PVP-I degermante, do PVP-I tópico e da clorexidina na degermação das mãos de graduandos da Faesa-Vitória, em procedimentos críticos. A coleta microbiológica foi realizada antes da degermação, após a degermação e uma hora após o uso de luvas. Foi possível concluir que: houve diferença significante entre o grupo água e sabão e os demais; a lavagem das mãos com água e sabão não inibiu o crescimento de Staphylococcus sp imediatamente; o PVP-I degermante e o PVP-I tópico e a clorexidina impediram o crescimento de qualquer micro-organismo no ato de seu uso e 1 hora depois

Evaluation of virucidal activity of three commercial disinfectants and formic acid using bovine enterovirus type 1 (ECBO virus), mammalian orthoreovirus type 1 and bovine adenovirus type 1.

A modified version of the test method of the Comité Européen de Normalisation (CEN) was developed using formic acid and three commercial disinfectants to evaluate virucidal activity against three non-enveloped viruses, bovine enterovirus type 1 (ECBO virus), mammalian orthoreovirus type 1 and bovine adenovirus type 1 (BAV 1). Determination of the effects of temperature was carried out at 20 and 10 degrees C. All tests with protein load used bovine serum albumin (BSA) and yeast extract. The investigations were performed in suspension tests and in carrier tests using poplar wood virus carriers. The carrier tests showed that ECBO virus could be inactivated at 20 degrees C with 1% formic acid within a 60 min reaction time. For disinfection of ECBO virus at 10 degrees C within 60 min, a 2% concentration of formic acid was necessary. Formic acid was ineffective against reovirus and bovine adenovirus and cannot be recommended as a reference disinfectant. Inactivation of ECBO virus and adenovirus type 1 using a disinfectant containing aldehydes and alcohols could be achieved, but only at room temperature. The disinfection of reovirus type 1 at room temperature with this product was possible without a protein load. This disinfectant exhibited disinfection ability at 10 degrees C at a concentration of more than 2% or with a longer exposure time. A disinfectant containing aldehydes was effective at room temperature but its effect was reduced in the presence of organic matter. Inactivation at 10 degrees C was found only against adenovirus. The fourth disinfectant, which contained peroxiacetic acid, inactivated all test viruses at a concentration of 0.5% within 15 min independent of temperature and protein load.

[Occupational exposure to glutaraldehyde during its use in chemical disinfection of endoscopes]. / Esposizione occupazionale a glutaraldeide nel corso della disinfezione chimica di endoscopi.

BACKGROUND: To evaluate the air pollution experimentally produced by different solutions of glutaraldehyde due to the activity of chemical disinfection in a flexible endoscopy unit. METHODS: The glutaraldehyde environment concentrations due to the use of 3 solutions (2% solution and its 1:5 and 1:20 dilutions) were measured by liquid chromatography after sampling on specific cartridges and by fotoacoustic method. RESULTS: Only after the use of the most concentrated solution it was possible to detect glutaraldehyde in the environment air, with values between 0.2 and 0.3 mg/m3 and during specific activities such as after shaking the disinfecting solutions. CONCLUSIONS: When the usual preventive recommendations are respected, the use of 1:5 and 1:20 solution of 2% glutaraldehyde products does not produce air concentrations of the aldehyde exceeding the current, even restrictive, limits proposed by industrial hygienists.

Evaluación antimicrobiana de 4 productos derivados del ácido piroleñoso para su posible utilización como desinfectantes / Antimicrobial evaluation of 4 products derived from the pirolegneous acid for their possible use as disinfectants

Se evaluó la efectividad antimicrobiana de 4 productos derivados del ácido piroleñoso (LQ 501-10, LQ 501-20, LQ 502-10 y LQ 502-20), según la metodologia CAME. Los 4 productos tienen buena efectividad antimicrobiana a la concentración del 6 por ciento. El estudio práctico en áreas quirúrgicas mostró una gran reducción de unidades formadoras de colonias después de la desinfección. En el estudio toxicológico se aprecia que los 4 productos son aptos para el uso propuesto. Se recomienda su utilización como desinfectantes de superficie (paredes, pisos, mesetas, etc), además pueden emplearse como limpiador. Los 4 productos formulados se pusieron en práctica y se incluyeron en el Registro de Productos Sanitarios

Comparative evaluation of two surgical scrub preparations in cattle.

One hundred seventeen cattle that had undergone surgery were assigned randomly to two preoperative skin preparation protocols. Group 1 (60 animals) skin preparation was with povidoneiodine soap and isopropyl alcohol, whereas group 2 (57 animals) had skin preparation with chlorhexidine gluconate and isopropyl alcohol. Quantitative microbial culture plates were used to estimate the number of colony forming units (CFUs) before skin preparation (prescrub), after skin preparation (postscrub), after surgery (postoperative), and in room air (environment). A significant decrease in CFU occurred postscrub for both skin preparations (P < .05). Chlorhexidine and alcohol preparation resulted in significantly fewer CFUs (LSMean +/- SE = 2.79 CFU +/- 1.74) and a greater percentage reduction in CFUs (98.64% +/- 2.01) postscrub than providone and alcohol (LSMean +/- SE = 10.27 CFUs +/- 1.51, 93.29% +/- 1.85); (P < .005). Group 2 had a significantly higher frequency of negative cultures postscrub (49.1%) compared with group 1 (18.3%) (P < .001). The number of postoperative CFUs were not significantly different between the two treatment groups. Wound infection frequency for clean surgical procedures was not significantly different between the two skin preparation protocols (group 1 = 9.8%, group 2 = 10.7%), however, infection frequency was significantly higher for surgical procedures with a ventral abdominal approach (5 of 14, 35.7%,) compared with a flank approach (1 of 41, 2.4%) or other approaches (orthopedic procedures) (1 of 16, 6.3%) (P < .05). Both skin preparation protocols were effective and safe in decreasing the skin microflora population of cattle before surgery and although preparation with chlorhexidine gluconate and alcohol resulted in less CFUs immediately postscrub, the frequency of surgical wound infection was similar for both protocols.