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.

Compliance with hand sanitizer quality during the SARS-CoV-2 pandemic: Assessing the impurities in an ethanol plant.

Using alcohol-based disinfectants is an effective method for preventing the spread of COVID-19. However, non-traditional manufacturers of alcohol-based disinfectants, such as ethanol plants, need to undergo additional treatment to curb their impurities to limits set by the Food and Drug Association (FDA) to produce alcohol-based disinfectants. To transform them to disinfectant-grade alcohol, 17 process streams in a dry-mill ethanol plant were analyzed to determine the quality parameters for acetaldehyde, acetal, propanol, methanol, and water, including chemical oxygen demand, total suspended solids, and nutrients. Results suggest that the process stream generated by the distillation column requires further treatment because the acetaldehyde and acetal concentrations are significantly higher than the impurity limit set by the FDA. The addition of a second distillation column could be a potential method for addressing impurities and it will have minimal influence on hazardous air pollutant generation and water use.

Evaluating the Virucidal Activity of Disinfectants According to European Union Standards.

The disinfection of surfaces in medical facilities is an important element of infection control, including the control of viral infections such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Preparations used for surface disinfection are typically characterized via their activity against test organisms (i.e., viruses, bacteria and fungi) in the laboratory. Typically, these methods use a suspension of the test organism to assess the bactericidal, fungicidal or virucidal activity of a given preparation. However, such suspension methods do not fully imitate real-life conditions. To address this issue, carrier methods have been developed, in which microorganisms are applied to the surface of a carrier (e.g., stainless steel, glass and polyvinyl chloride (PVC)) and then dried. Such methods more accurately reflect the applications in real-life clinical practice. This article summarizes the available methods for assessing the virucidal activity of chemical disinfectants for use in medical facilities based on the current European standards, including the activity against coronaviruses.

The European tiered approach for virucidal efficacy testing - rationale for rapidly selecting disinfectants against emerging and re-emerging viral diseases.

When facing an emerging virus outbreak such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a quick reaction time is key to control the spread. It takes time to develop antivirals and vaccines, and implement vaccination campaigns. Therefore, preventive measures such as rapid isolation of cases and identification and early quarantine of cases' close contacts-as well as masks, physical distancing, hand hygiene, surface disinfection and air control-are crucial to reduce the risk of transmission. In this context, disinfectants and antiseptics with proven efficacy against the outbreak virus should be used. However, biocidal formulations are quite complex and may include auxiliary substances such as surfactants or emollients in addition to active substances. In order to evaluate disinfectants' efficacy objectively, meaningful efficacy data are needed. Therefore, the European Committee for Standardisation technical committee 216 'Chemical disinfectants and antiseptics' Working Group 1 (medical area) has developed standards for efficacy testing. The European tiered approach grades the virucidal efficacy in three levels, with corresponding marker test viruses. In the case of SARS-CoV-2, disinfectants with proven activity against vaccinia virus, the marker virus for the European claim 'active against enveloped viruses', should be used to ensure effective hygiene procedures to control the pandemic.

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.

Efficacies of the original and modified World Health Organization-recommended hand-rub formulations.

The World Health Organization (WHO) hand-rub formulations have been in use around the world for at least the past 10 years. The advent of coronavirus disease 2019 (COVID-19) has further enhanced their use. We reviewed published efficacy data for the original and modified formulations. Only efficacy data according to the European Norms (EN) were found. The bactericidal efficacy of the original formulations was, under practical conditions, partly insufficient (EN 1500, only effective in 60 s; EN 12791, efficacy too low in 5 min). The first modification with higher alcohol concentrations improves their efficacy as hygienic hand rub (effective in 30 s). The second (0.725% glycerol) and third (0.5% glycerol) modification improves their efficacy for surgical hand preparation (effective in 5 and 3 min). The original and second modified formulations were tested and demonstrate activity against enveloped viruses including severe acute resiratory syndrome coronavirus 2 (SARS-CoV-2) in 30 s. The ethanol-based formulation is also active against some non-enveloped test viruses in 60 s (suspension tests, EN 14476). In-vivo data on the formulations would provide a more reliable result on the virucidal efficacy on contaminated hands but are currently not available. Nevertheless, the most recent modifications should be adopted for use in healthcare.

Potential methanol toxicity and the importance of using a standardised alcohol-based hand rub formulation in the era of COVID-19.

OBJECTIVES: Hand sanitisers are urgently needed in the time of COVID-19, and as a result of shortages, some people have resorted to making their own formulations, including the repurposing of distilleries. We wish to highlight the importance of those producing hand sanitisers to avoid methylated spirits containing methanol and to follow WHO recommended formulations. METHODS: We explore and discuss reports of methanol toxicity through ingestion and transdermal absorption. We discuss the WHO formulations and explain the rationale behind the chosen ingredients. SHORT CONCLUSION: We advise those producing hand sanitisers to follow WHO recommended formulations, and advise those producing hand sanitisers using methylated spirits, to avoid formulations which contain methanol.

Hygienic and cosmetic care habits in polish women during COVID-19 pandemic.

BACKGROUND: COVID-19 pandemic influences a lot of aspects of human life. Particularly, hygienic habits are affected. OBJECTIVES: Changes in washing and cosmetic standards during the pandemic toward the past are in the focus of our interest. MATERIAL AND METHODS: The questionnaire study was conducted anonymously in 140 women. The examination concerned pre- and during-pandemic routine hygiene activities such as hands washing, hair washing, bathing, the use of disinfectants, and use of specific type of cosmetics. RESULTS AND DISCUSSION: Compared were data before and during pandemic. Responders declared increased handwashing and taking shower after coming back home and after using local city transportation. We found also that increased use of disinfectants during COVID-19 pandemic. In contrary to that, number of people washing their hair decreased slightly. Work documents that profile of used cosmetics was changed; increasing hand cream use and decreasing in makeup cosmetics. Nearly, half of the respondents declare that they will maintain new habits also after the pandemic has ended.

Bactericidal Activity of Ready-To-Use Alcohol-Based Commercial Wipes According to EN 16615 Carrier Standard.

BACKGROUND: The effectiveness of ready-to-use disinfectant wipes was previously assessed in standardized suspension tests, which were inadequate because they ignored that the wipes are rubbed against a surface. Thus, we assessed the effectiveness of commercially available disinfectant wipes impregnated with an alcoholic solution according to the 16615 standard, which includes a test with mechanical action. METHODS: According to the EN 16615 standard, under clean conditions, four squares (5cm x 5 cm), placed next to one another, were marked on a test surface. Enterococcus hirae, Pseudomonas aeruginosa, and Staphylococcus aureus were inoculated on the leftmost square, and a wipe impregnated with an alcoholic solution was placed to the left of that square. Then, the wipe was pressed with a 2.5 kg weight and moved to the right and back to the left. After contact times of 1, 5, 10, or 15 minutes, we measured the reduction in bacterial load. RESULTS: Alcohol-based ready-to-use commercial wipes did not show sufficient bactericidal activity at the contact times of 1, 5, 10 and 15 minutes. Wipes containing propan-1-ol and a mixture of propan-1-ol and propan-2-ol were active against Pseudomonas aeruginosa at the contact times of 1 minute and 15 minutes. None of the examined wipes were active against Enterococcushirae or Staphylococcusaureus. CONCLUSION: Bactericidal parameters of ready-to-use disinfectant wipes should be determined in surface tests, in addition to suspension tests, because suspension tests do not simulate the conditions under which disinfectant wipes are used in practice.

Variability of residual chlorine in swimming pool water and determination of chlorine consumption for maintaining hygienic safety of bathers with a simple mass balance model.

Trial-and-error chlorination as a conventional practice for swimming pool water disinfection may fail to consistently maintain the pool's residual chlorine within regulatory limits. This study explored the variability of residual chlorine and other common water quality parameters of two sample swimming pools and examined the potential of using a mass balance model for proactive determination of chlorine consumption to better secure the hygienic safety of bathers. A lightly loaded Pool 1 with a normalized bather load of 0.038 bather/m3/day and a heavily loaded Pool 2 with a normalized bather load of 0.36 bather/m3/day showed great variances in residual free and combined chlorine control by trial-and-error methods due to dynamic pool uses. A mass balance model based on chemical and physical chlorine consumption mechanisms was found to be statistically valid using field data obtained from Pool 1. The chlorine consumption per capita coefficient was determined to be 4120 mg/bather. The predictive method based on chlorine demand has a potential to be used as a complementary approach to the existing trial-and-error chlorination practices for swimming pool water disinfection. The research is useful for pool maintenance to proactively determine the required chlorine dosage for compliance of pool regulations.

Evaluation of the Efficacy of Commercial Disinfectants Against Fusarium oxysporum f. sp. cubense Race 1 and Tropical Race 4 Propagules.

Panama disease caused by Fusarium oxysporum f. sp. cubense has devastated banana production worldwide. This work aimed to determine effective disinfectants against two races of F. oxysporum f. sp. cubense, race 1 and tropical race 4 (TR4), for implementation with on-farm biosecurity procedures against this disease following the outbreak of TR4 in North Queensland in 2015. A total of 32 commercial disinfectants were screened and their activity was assessed after ≤30 s, 5 min, 30 min, and 24 h of contact with an F. oxysporum f. sp. cubense suspension containing 105 chlamydospores/ml without and with soil added (0.05 g/ml). Of the disinfectants tested, the quaternary ammonium compounds containing ≥10% active ingredient were found to be the most effective against both F. oxysporum f. sp. cubense races. These products, when used at a 1:100 dilution, completely inhibited the survival of all F. oxysporum f. sp. cubense propagules across all the contact times regardless of the absence or presence of soil. The bioflavonoid product EvoTech 213 and bleach (10% sodium hypochlorite) used at a 1:10 dilution also eliminated all F. oxysporum f. sp. cubense propagules across all the contact times. None of the detergent-based or miscellaneous products tested were completely effective against both F. oxysporum f. sp. cubense races even used at a 1:10 dilution. Soil decreases the efficacy of disinfectants and therefore must be removed from contaminated items before treatments are applied.

The effectiveness of fishery net dips: Advice for the improvement of biosecurity measures.

Disease poses a major threat to aquaculture and commercial and recreational fisheries globally. Biosecurity measures have been implemented; however, empirical evidence of their efficacy in situ is lacking. Here, we present the results from a study conducted to examine the effectiveness of disinfectant net dips. Samples were collected from disinfectant net dips at 25 recreational fisheries in south-west England and assessed to determine (a) the level of bacterial contamination and (b) the reduction in titre of a target virus (infectious pancreatic necrosis virus, IPNV) following a contact time of 2 and 5 min. In addition, the study examined the reduction in target virus titre following exposure to laboratory prepared Virkon® , representing "clean," "dirty" and "diluted and dirty" conditions, for 2 and 5 min. Bacterial contamination was high in 64% of disinfectant samples, and, 76% of disinfectant samples did not effectively reduce the target virus titre in 2 or 5 min. Virus titre was successfully reduced following exposure to laboratory prepared Virkon® for 2 or 5 min, although dilution and contamination reduced the effectiveness. These results suggest that disinfectant net dips may not be working effectively on a high proportion of fishery sites. We provide recommendations for improving biosecurity.

Regulated and emerging disinfection by-products in recycled waters.

Disinfection is an integral component of water treatment performed daily on large volumes of water worldwide. Chemical disinfection may result in the unintended production of disinfectant by-products (DBPs) due to reactions between disinfectants and natural organic matter present in the source water. Due to their potential toxicity, levels of DBPs have been strictly regulated in drinking waters for many years. With water reuse now becoming more common around the world DBPs are increasingly becoming a concern in recycled waters, where a much larger amount and variety of compounds may be formed due to a higher abundance and diversity of organic material in the source waters. Regulation of DBPs in recycled waters is limited; generally, drinking water regulations are applied in place of specific guidelines for recycled waters. Such regulations are set for only 11, commonly observed, compounds of the 600+ that may, potentially, be found. In this review an overview of current research in this area is provided, the types of compounds that have been observed, methods for their analysis and possible regulation are also discussed. Through this review it is evident that there is a knowledge gap for the occurrence of DBPs in recycled waters, especially when comparing this information to that available for drinking waters. The concentrations of DBPs observed in recycled waters are seen to be higher than those in drinking water, though still within potable threshold limits. It is clear that there is a need for the analysis and understanding of a larger suite of compounds in recycled waters, as these will most likely be the source of future, global renewable water.

Efficacy of "HLE"-a multidrug efflux-pump inhibitor-as a disinfectant against surface bacteria.

We evaluated the efficacy of a new disinfectant product, HLE, to inhibit multiple species of planktonic and biofilm bacterial cultures. The HLE disinfectant comprised of EDTA, lactic acid and hydrogen peroxide, and our data indicated that the disinfectant had effective antimicrobial and anti-biofilm activity even at low concentrations (0.15% to 0.4% HLE, v/v). Furthermore, the HLE disinfectant destabilized biofilm structures eradicated them due to the synergistic effect of EDTA and both antimicrobials (lactic acid and hydrogen peroxide), as revealed by confocal laser scanning microscopy. Additionally, sub-inhibitory concentrations of HLE disinfectant, with EDTA as an efflux pump inhibitor, inhibited the expression of multidrug EfrAB, NorE and MexCD efflux pumps in both planktonic and biofilm cultures. This could provide an alternative way to disinfect surfaces to avoid spreading multi-drug resistant strains in the food chain and the environment by decreasing efflux pump expression and consequently reducing the antibiotic selective pressure caused by systemic antibiotics and disinfectant use.

Preliminary Efficacy Testing of the Disinfectant MicrobeCare XLP for Potential Use in Military Operational Environments.

Introduction: A safe, easy-to-use, permanently bonded antiseptic that does not require post-exposure bioload reduction but maintains effectiveness over time would have far-reaching implications across multiple industries. Health care is one such arena, particularly in austere military settings where resources are at a premium. MicrobeCare XLP (MicrobeCare, Buffalo Grove, IL, USA) is a commercially available spray-on agent that is advertised to covalently bond to surfaces and provide a long-lasting antimicrobial coating inhospitable to >99.99% of surface microorganisms. A pilot study was devised to gather baseline data regarding product efficacy and laboratory parameters before consideration of extended investigations and military utilization. The product manufacturer recommends bioload reductions before product application, following product application, and after each pathogenic exposure. To investigate the product's efficacy in circumstances more closely simulating a military operational setting in which post-pathogenic exposure bioload reduction would not be possible, this step was deliberately excluded from the test sequences. Materials and Methods: Using autoclaved surgical forceps, growth of Staphylococcus aureus and Acinetobacter baumannii was evaluated in a controlled manner under multiple conditions. Test variations included duration of submersion in the MicrobeCare XLP solution and air-drying and a second autoclave sterilization. Control and treated forceps were exposed to a bacterial suspension and air-dried before being submerged in sterile saline and vortex mixed. The saline solution was serially diluted and plated on tryptic soy agar (TSA) II plates. Plates were incubated for 24 h and bacterial colony-forming units (CFU)/mL were counted. Results: Statistical significance was defined according to the American Society for Testing and Materials (ASTM) International passing criteria of 3 Log10 or 99.9% reduction of microorganisms. Additionally, p-values were calculated using two-tailed unpaired two-sample t-tests with unequal variance with a threshold of 0.05. In the S. aureus tests, none of the reduction calculations met the ASTM International passing criteria. In addition, the difference between the means of the colony counts in the MicrobeCare XLP-treated forceps and untreated control forceps was not statistically significant (p-value 0.109). Conversely, in the A. baumannii tests, each of the percent reduction calculations met the ASTM International passing criteria; the difference between the means of the colony counts in the treatment and control groups was statistically significant (p-value 0.008). Conclusion: In these independent tests, MicrobeCare XLP effectively prevented growth of A. baumannii but had unpredictable results suppressing S. aureus. These results may relate to inherent properties of the bacteria or autoclave exposure, although the manufacturer asserts that the coating withstands such degradation. Additional testing could be performed using a broader range of microorganisms and exposure to varying conditions including other sterilization methods.

Investigation of some disinfection chemicals and water quality parameters in swimming pools in the city center and districts of Canakkale, Turkey.

In this study, the variations in concentrations of some disinfection chemicals such as cyanuric acid (CyA), free chlorine (FC), and residual chlorine (RC), which affect human health, were investigated in the water of swimming pools. In addition, quality parameters such as temperature, pH, and total alkalinity (TA) in 44 swimming pools located in the city center and districts of Canakkale, Turkey, were examined in the summer period. While FC and RC amounts were analyzed using tablet tests with N-N-diethyl phenylenediamine (DPD 1) and potassium iodine (DPD 3) using the colorimetric method in the comparator, TA and CyA levels were measured with a photometric method. Temperature and pH were measured using YSI 556 MPS. Levels of CyA, FC, RC, pH, temperature, and TA varied between 0.00 and 725.0 mg L-1 (108.0 ± 111.4 mg L-1), 0.00 and 5.00 mg L-1 (1.60 ± 0.962 mg L-1), 0 and 0.55 mg L-1 (0.087 ± 0.059), 6.40 and 8.20 mg L-1 (7.30 ± 0.038 mg L-1), 22.0 and 32.0 °C (27.6 ± 1.45 °C), and 0.00 and 391.0 mg L-1 (129.3 ± 89.0), respectively. The findings were compared to standard limit values of the Ministry of Health of the Turkish Republic and other countries. Not only maximum concentrations of CyA but also the average concentrations exceeded the standard limit values of different countries in July and August with high tourism activity in Turkey. Although there is no problem in view of average values of other quality parameters, there are some problems in view of the maximum values in pool waters compared to standard limit values.

Microbiologic Testing for 503A Sterile-Compounding Pharmacies.

Compounding pharmacists must ensure that the sterile preparations they dispense are free of microbiologic contamination. Working in a cleanroom under controlled conditions (proper differential air pressure, temperature, and humidity; acceptable levels of viable and nonviable airborne particles and surface counts, etc.) and testing the efficacy of cleaning and disinfecting practices via environmental monitoring (viable-air and surface testing, glove-fingertip-thumb testing, etc.) are essential to preparing contamination-free medications. Sterile-compounding pharmacists must understand how to monitor their cleanroom environment and, if they perform testing in house, to interpret the results of simple microbiologic tests (a skill helpful even when tests are outsourced to a contract laboratory). In this article, which pertains to 503A sterile compounding, and is based on the current version of United States Pharmacopeia (USP) Chapter <797>, basic concepts in microbiology and the microbial tests that can be performed and interpreted in house and those that must be outsourced are discussed. Streamlining communication with contract laboratory personnel is reviewed. Requirements for an inhouse microbiology laboratory are presented, and the advantages and disadvantages of inhouse and outsourced testing are examined. A list of suggested reading is provided for easy reference. In a subsequent article, environmental monitoring and analysis will be addressed in detail.

An Increase in Healthcare-Associated Clostridium difficile Infection Associated with Use of a Defective Peracetic Acid-Based Surface Disinfectant.

BACKGROUND We investigated an increase in the incidence of healthcare-associated Clostridium difficile infection (CDI) that occurred following a change from a bleach disinfectant to a peracetic acid-based disinfectant. OBJECTIVE To evaluate the efficacy of the peracetic acid-based disinfectant. DESIGN Laboratory-based product evaluation. METHODS The commercial peracetic acid-based product is activated on site by mixing a small volume of concentrated hydrogen peroxide and peracetic acid present in a "SmartCap" reservoir with the remaining contents of the container. We measured concentrations of peracetic acid in newly activated and in-use product and determined the stability of nonactivated and activated product. We tested the efficacy of the product against C. difficile spores using the American Society for Testing and Materials standard quantitative carrier disk test method. RESULTS Measured concentrations of peracetic acid (50-800 parts per million [ppm]) were significantly lower than the level stated on the product label (1,500 ppm), and similar results were obtained for containers from multiple lot numbers and from another hospital. Product with peracetic acid levels below 600 ppm had significantly reduced activity against C. difficile spores. Peracetic acid concentrations were reduced markedly after storage of either activated or nonactivated product for several weeks. The Environmental Protection Agency confirmed the finding of low disinfectant levels and ordered discontinuation of sale of the product. CONCLUSION Use of a defective peracetic acid-based surface disinfectant may have contributed to an increase in healthcare-associated CDI. Our findings highlight the importance of evaluating the efficacy of liquid disinfectants in healthcare settings. Infect Control Hosp Epidemiol 2017;38:300-305.

Disinfection of aircraft : Appropriate disinfectants and standard operating procedures for highly infectious diseases.

For infectious diseases caused by highly pathogenic agents (e. g., Ebola/Lassa fever virus, SARS-/MERS-CoV, pandemic influenza virus) which have the potential to spread over several continents within only a few days, international Health Protection Authorities have taken appropriate measures to limit the consequences of a possible spread. A crucial point in this context is the disinfection of an aircraft that had a passenger on board who is suspected of being infected with one of the mentioned diseases. Although, basic advice on hygiene and sanitation on board an aircraft is given by the World Health Organization, these guidelines lack details on available and effective substances as well as standardized operating procedures (SOP). The purpose of this paper is to give guidance on the choice of substances that were tested by a laboratory of Lufthansa Technik and found compatible with aircraft components, as well as to describe procedures which ensure a safe and efficient disinfection of civil aircrafts. This guidance and the additional SOPs are made public and are available as mentioned in this paper.