Susceptibility of HPV16 and 18 to high level disinfectants indicated for semi-critical ultrasound probes

Recommendations for the Cleaning of Endocavity Ultrasound Transducers Between Patients

The COVID-19 pandemic highlighted the importance of infection prevention and control measures for all medical procedures, including ultrasound examinations. As the use of ultrasound increases across more medical modalities, including point-of-care ultrasound, so does the risk of possible transmission from equipment to patients and patients to patients. This is particularly relevant for endocavity transducers, such as trans-vaginal, trans-rectal and trans-oesophageal, which could be contaminated with organisms from blood, mucosal, genital or rectal secretions. This article proports to update the WFUMB 2017 guidelines which focussed on the cleaning and disinfection of trans-vaginal ultrasound transducers between patients.

A review on sterilization methods of environmental decontamination to prevent the coronavirus SARS-CoV-2 (COVID-19 virus): A new challenge towards eco-friendly solutions

In recent years, the COVID-19 pandemic is currently wreaking havoc on the planet. SARS-CoV-2, the Severe Acute Respiratory Syndrome Coronavirus, is the current term for this outbreak. Reports about this novel coronavirus have been presented since the pandemic's breakout, and they have demonstrated that it transmits rapidly from person to person, primarily by droplets in the air. Findings have illustrated that SARS-CoV-2 can survive on surfaces from hours to days. Therefore, it is essential to find practical solutions to reduce the virus's impact on human health and the environment. This work evaluated common sterilization methods that can decontaminate the environment and items. The goal is that healthcare facilities, disease prevention organizations, and local communities can overcome the new challenge of finding eco-friendly solutions. Further, a foundation of information encompassing various sterilization procedures and highlighting their limits to choose the most appropriate method to stop disease-causing viruses in the new context has been presented. The findings of this crucial investigation contribute to gaining insight into the comprehensive sterilization approaches against the coronavirus for human health protection and sustainable environmental development.

Reprocessing semicritical items: An overview and an update on the shift from HLD to sterilization for endoscopes

BACKGROUND

Semicritical medical devices are defined as items that come into contact with mucous membranes or nonintact skin (e.g., gastrointestinal endoscopes, endocavitary probes). Such medical devices require minimally high-level disinfection.

METHODS

Analyze the methods used to reprocess semicritical medical devices and identify methods and new technologies to reduce the risk of infection.

RESULTS

The reprocessing methods for semicritical medical devices is described as well as a shift from high-level disinfection to sterilization for lumened endoscopes.

CONCLUSIONS

Strict adherence to current guidelines and transition to sterilization for endoscopes is required as more outbreaks have been linked to inadequately disinfected endoscopes and other semicritical items than any other reusable medical devices.

Assessing nonsexual transmission of the human papillomavirus (HPV): Do our current cleaning methods work?

Human papillomavirus (HPV) is thought to be sexually transmitted; however, there have been a few studies investigating a possible iatrogenic source of infection. Therefore, it is important to assess the cleaning methods of reusable medical devices. This study assessed whether cleaning methods of flexible endoscopes in an otolaryngology clinic are effective against HPV. There were 24 patients with a history of head and neck cancer in the study; however, two outliers were excluded. Nine patients were confirmed to have HPV-associated cancer. PCR was used to measure and quantify the viral genomes of samples collected before and after cleaning. After cleaning, few HPV+ samples had endoscopes with less DNA than before cleaning. Additionally, for several patients with non-HPV-associated head and neck cancer, PCR showed more DNA after cleaning than before cleaning, suggesting residual HPV DNA within the cleaning solution. There was no significant difference (p > 0.05) between pre- and post-cleaning in both cohorts. Current cleaning methods of reusable endoscopes may not be effective in completely removing viral DNA.

Infection Transmission Associated With Contaminated Ultrasound Probes: A Systematic Review

A systematic review of seven studies on infections related to contaminated ultrasound probes showed that the infections were related to a failure in the decontamination process of ultrasound devices used on immature skin of neonates in an intensive care unit and transesophageal echocardiography probes. Six of the studies involved outbreaks in patients who underwent transesophageal echocardiography either during or after surgery or as a part of treatment for a nonsurgical cardiac condition. The evidence shows links between the infection outbreaks and environmental contamination, lack of standardized ultrasound probe disinfection processes, inadequate storage, and lack of monitoring of probe integrity. When personnel addressed the deficiencies (eg, improving the disinfection process, cleaning the probes immediately after use, inspecting the probes for defects), the infections ceased. Personnel involved with the reprocessing of ultrasound probes should clean, disinfect, inspect, and store ultrasound probes in a manner that maintains device integrity and prevents contamination.

Inactivation of Polyomavirus SV40 as Surrogate for Human Papillomaviruses by Chemical Disinfectants

Human papillomaviruses (HPV) are non-enveloped DNA viruses infecting cutaneous and mucosal squamous epithelia. Sexually transmitted HPV-types that are carcinogenic to humans such as HPV16 can induce cervical and other anogenital cancers. Virus transmission through fomites such as inadequately disinfected gynecological equipment is a further potential transmission route. Since HPV cannot be easily grown in cell culture, polyomavirus SV40 has been used as a surrogate virus when testing the virucidal activity of chemical disinfectants. So far, studies that have compared the virucidal activity of different disinfectants against HPV and SV40 are lacking. Here, we evaluated the susceptibility of HPV16 pseudovirus and SV40 to seven active biocidal substances using quantitative suspension tests. Ethanol, glutaraldehyde (GTA), dodecyldipropylentriamin (DPTA), and ortho-phthalaldehydes (OPA) were able to reduce the infectivity of HPV16 pseudovirus >99.99% after 5 min. In contrast, isopropanol, peracetic acid (PAA), and quaternary ammonium compounds with alkylamines (QAC) only led to a slight or no reduction in infectivity. Concerning SV40, only GTA (60 min contact time), PAA, and OPA had virus-inactivating effects. In conclusion, the virucidal activity of three out of seven disinfectants tested was different for HPV16 pseudovirus and SV40. In this study, SV40 was shown to be a reliable surrogate virus for HPV when testing isopropanol-, GTA-, QAC-, and OPA-based disinfectants.

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.

Streamlining Disease Risk Analysis for Wildlife Using the Shark Bay Bandicoot as a Model

Disease risk analysis (DRA) is a process for identifying significant disease risks and proposing measures to mitigate those risks. Although numerous methodologies for DRA exist, the IUCN Disease Risk Analysis Manual Jakob-Hoff et al. (World Organisation for Animal Health, Paris, pp 160, 2014) remains the gold standard for wild animal translocations. In some cases, however, constraints of time or resources demand compromises on the ideal methodology, and a cost-benefit assessment is required to determine the best approach. We propose a methodology modified from Jakob-Hoff et al. (World Organisation for Animal Health, Paris, pp 160, 2014) and Sainsbury and Vaughan-Higgins (Conserv Biol 26:442-452, 2012), using translocations of the Shark Bay bandicoot (SBB) (Perameles bougainville) as an example. In this study, 44 hazards were identified and described for Peramelidae species. We used hazard prioritization and "scoping" to develop a shortlist of hazards for detailed risk assessment, which excluded 35 of these hazards from further assessment. This approach enabled timely, efficient and cost-effective completion of the DRA while maintaining transparent evaluation of all disease risks. We developed a disease risk management strategy for SBB based on structured, evidence-based analysis of current information and established biosecurity practices and disease screening recommendations for future translocations. Our approach demonstrates a practical process for DRA and risk mitigation, which delivered management outcomes despite limited resources, variable knowledge of disease epidemiology and uncertain translocation pathways for the target species. Limitations are acknowledged, and further research will aim to objectively test this methodology compared to other available methods.

Dynamics of papillomavirus in vivo disease formation & susceptibility to high-level disinfection-Implications for transmission in clinical settings

BACKGROUND

High-level disinfection protects tens-of-millions of patients from the transmission of viruses on reusable medical devices. The efficacy of high-level disinfectants for preventing human papillomavirus (HPV) transmission has been called into question by recent publications, which if true, would have significant public health implications.

METHODS

Evaluation of the clinical relevance of these published findings required the development of novel methods to quantify and compare: (i) Infectious titres of lab-produced, clinically-sourced, and animal-derived papillomaviruses, (ii) The papillomavirus dose responses in the newly developed in vitro and in vivo models, and the kinetics of in vivo disease formation, and (iii) The efficacy of high-level disinfectants in inactivating papillomaviruses in these systems.

FINDINGS

Clinical virus titres obtained from cervical lesions were comparable to those obtained from tissue (raft-culture) and in vivo models. A mouse tail infection model showed a clear dose-response for disease formation, that papillomaviruses remain stable and infective on fomite surfaces for at least 8 weeks without squames and up to a year with squames, and that there is a 10-fold drop in virus titre with transfer from a fomite surface to a new infection site. Disinfectants such as ortho-phthalaldehyde and hydrogen peroxide, but not ethanol, were highly effective at inactivating multiple HPV types in vitro and in vivo.

INTERPRETATION

Together with comparable results presented in a companion manuscript from an independent laboratory, this work demonstrates that high-level disinfectants inactivate HPV and highlights the need for standardized and well-controlled methods to assess HPV transmission and disinfection.

FUNDING

Advanced Sterilization Products, UK-MRC (MR/S024409/1 and MC-PC-13050) and Addenbrookes Charitable Trust.

Infectious titres of human papillomaviruses (HPVs) in patient lesions, methodological considerations in evaluating HPV infectivity and implications for the efficacy of high-level disinfectants

BACKGROUND

Recent publications from a single research group have suggested that aldehyde-based high-level disinfectants (HLDs), such as ortho-phthalaldehyde (OPA), are not effective at inactivating HPVs and that therefore, patients may be at risk of HPV infection from medical devices. These results could have significant public health consequences and therefore necessitated evaluation of their reproducibility and clinical relevance.

METHODS

We developed methods and used standardised controls to: (1) quantify the infectious levels of clinically-sourced HPVs from patient lesions and compare them to laboratory-derived HPVs, (2) evaluate experimental factors that should be controlled to ensure consistent and reproducible infectivity measurements of different HPV genotypes, and (3) determine the efficacy of select HLDs.

FINDINGS

A novel focus forming unit (FFU) infectivity assay demonstrated that exfoliates from patient anogenital lesions and respiratory papillomas yielded infectious HPV burdens up to 2.7 × 103 FFU; therefore, using 2.2 × 102 to 1.0 × 104 FFU of laboratory-derived HPVs in disinfection assays provides a relevant range for clinical exposures. RNase and neutralising antibody sensitivities were used to ensure valid infectivity measures of tissue-derived and recombinant HPV preparations. HPV infectivity was demonstrated over a dynamic range of 4-5 log10; and disinfection with OPA and hypochlorite was achieved over 3 to >4 log10 with multiple genotypes of tissue-derived and recombinant HPV isolates.

INTERPRETATION

This work, along with a companion publication from an independent lab in this issue, address a major public health question by showing that HPVs are susceptible to HLDs.

FUNDING

Advanced Sterilization Products; US NIH (R01CA207368, U19AI084081, P30CA118100).

Society for Maternal-Fetal Medicine Special Statement: Reducing the risk of transmitting infection by transvaginal ultrasound examination

Recent surveys have shown widespread lapses in the procedures used to reduce the risk of transmitting infection via medical devices. Transvaginal ultrasound examination has the potential to transmit vaginal infections, including human papillomavirus. Areas of particular concern are the use of probe covers with high rates of leakage, disinfectants that are not effective against human papillomavirus, and coupling gel from multiple-use containers. We reviewed these issues, and we recommend 4 steps to reduce the risk of transmitting infection. First, during every transvaginal ultrasound exam, the probe should be covered with a sterile, single-use "viral barrier" cover or a condom. Second, sterile, single-use ultrasound gel packets should be used. Third, after every examination, the probe should be cleaned to remove any visible gel or debris. Finally, after cleaning, the probe should undergo high-level disinfection using an agent with proven efficacy against the human papillomavirus, including hydrogen peroxide, hypochlorite, or peracetic acid. Glutaraldehyde, orthophthalaldehyde, phenols, and isopropyl alcohol have virtually no efficacy against the human papillomavirus.

A comparative carbon footprint analysis of disposable and reusable vaginal specula

BACKGROUND

Healthcare systems in the United States have increasingly turned toward the use of disposable medical equipment in an attempt to save time, lower costs, and reduce the transmission of infections. However, the use of disposable instruments is associated with increased solid waste production and may have negative impacts on the environment, such as increased greenhouse gas emissions.

OBJECTIVE

The purpose of this study was to inform this discussion; we applied life cycle assessment methods to evaluate the carbon footprints of 3 vaginal specula: a single-use acrylic model and 2 reusable stainless steel models.

STUDY DESIGN

The functional unit of the study was defined as the completion of 20 gynecologic examinations by either type of speculum. The greenhouse gas emissions (eg, carbon dioxide, methane, nitrous oxide) across all life cycle stages, which includes material production and manufacturing, transportation, use and reprocessing, and end-of-life, were analyzed with the use of SimaPro life cycle assessment software and converted into carbon dioxide equivalents.

RESULTS

The reusable stainless steel grade 304 speculum was found to have a lesser carbon footprint over multiple model scenarios (different reprocessing techniques, autoclave loading/efficiency, and number of uses) than either the reusable stainless steel grade 316 or the disposable acrylic specula. The material production and manufacturing phase contributed most heavily to the total life cycle carbon footprint of the acrylic speculum, whereas the use and reprocessing phase contributed most to the carbon footprints of both stainless steel specula.

CONCLUSION

The use of disposable vaginal specula is associated with increased greenhouse gas equivalents compared with reusable alternatives with no significant difference in clinical utility. These findings can be used to inform decision-making by healthcare systems, because they weigh a wide range of considerations in making final purchase decisions; similar analytic methods can and should be applied to other components of health systems' waste streams.

Design and implementation of the infection prevention program into risk management: Managing high level disinfection and sterilization in the outpatient setting

Reusable, invasive medical devices within the outpatient setting pose a risk for patient harm. Ineffective disinfection of medical devices can potentially lead to transmission of pathogens between patients; and improper handling can lead to patient injury. A risk assessment was conducted, and the results strongly supported the necessity to develop a robust infection prevention program within the risk management department. This exclusive program was a proactive approach to preventing patient exposure within our healthcare system. Designing and integrating an Infection Prevention program into the Risk Management Department presented challenges, especially with the magnitude of devices and lack of standardization throughout our 33 clinics. Key components of the program included: capturing an accurate inventory of devices throughout the system, hiring a sterile processing expert, engaging support from senior leadership, adhering to rigorous auditing processes, and establishing a staff competency training structure. Since the program was launched 2 years ago, outcomes include: identification of high-risk practices with immediate resolution, increase in average clinic compliance to device reprocessing standards from 88% to 99%, elimination of 71% of scope reprocessing and 39% of instrument sterilization by clinic staff with allocation to central sterile processing departments, and development of a staff competency training structure.

Sanitizing agents for virus inactivation and disinfection

Viral epidemics develop from the emergence of new variants of infectious viruses. The lack of effective antiviral treatments for the new viral infections coupled with rapid community spread of the infection often result in major human and financial loss. Viral transmissions can occur via close human-to-human contact or via contacting a contaminated surface. Thus, careful disinfection or sanitization is essential to curtail viral spread. A myriad of disinfectants/sanitizing agents/biocidal agents are available that can inactivate viruses, but their effectiveness is dependent upon many factors such as concentration of agent, reaction time, temperature, and organic load. In this work, we review common commercially available disinfectants agents available on the market and evaluate their effectiveness under various application conditions. In addition, this work also seeks to debunk common myths about viral inactivation and highlight new exciting advances in the development of potential sanitizing agents.

Effect of a Condom Cover on Vaginal Photoplethysmographic Responses

INTRODUCTION

The vaginal photoplethysmograph (VPP) is a reusable intravaginal device often employed in sexual psychophysiology studies to assess changes in vaginal blood flow, an indicator of sexual arousal.

AIM

To test whether placing a disposable cover on the VPP probe impacts the acquired data. A condom cover would reduce risk of disease transmission and likely increase participant comfort but may negatively impact the VPP signal.

METHOD

The genital responses of 25 cisgender women (mean age = 21.3 years, standard deviation = 2.6) were assessed with VPP in a within-subjects design with 2 conditions-with and without a polyisoprene condom cover. Sexual responses were elicited by audiovisual film clips that varied in erotic intensity: nonsexual (nonsexual male-female interaction), low-intensity sexual (nude exercise), and high-intensity sexual (male-female intercourse). Women continuously rated their sexual arousal during stimulus presentations.

MAIN OUTCOME MEASURE

Change in vaginal pulse amplitude and also self-reported sexual arousal.

RESULTS

The magnitude of sexual response to each stimulus category and the overall pattern of results were found to be highly similar in the cover-off and cover-on conditions. The high-intensity sexual stimulus category elicited a greater sexual response than all other categories. The low-intensity sexual category elicited a (small) genital response in only the cover-on condition, although we suspect this is a spurious finding. There was no difference in the average number of edited movement artifacts across conditions.

CLINICAL IMPLICATIONS

Potential benefits of encasing the VPP probe with a protective cover include enhanced participant safety and comfort, especially if assessing genital responses of high-risk or immunocompromised samples. The use of a cover complies with current guidelines for reprocessing semi-critical medical devices (eg, vaginal ultrasound probes) in many regions.

STRENGTHS & LIMITATIONS

Although the idea of a VPP probe cover had been discussed among sexual psychophysiology researchers, this is the first study to empirically test whether a cover could jeopardize VPP data. Potential limitations include the use of a 10-Hz VPP sampling rate and a cover that was not tailored to the size of the VPP probe.

CONCLUSION

Placing a protective cover on the VPP probe did not appear to meaningfully impact sexual arousal or the VPP data. Based on these results and the potential advantages of a protective cover, researchers may wish to integrate the use a condom cover in their experiment protocols and clinical applications. Sawatsky ML, Lalumière ML. Effect of a Condom Cover on Vaginal Photoplethysmographic Responses. J Sex Med 2020; 17:702-715.

The ability of two chlorine dioxide chemistries to inactivate human papillomavirus-contaminated endocavitary ultrasound probes and nasendoscopes

Sexual transmission is the most common pathway for the spread of Human papillomavirus (HPV). However, the potential for iatrogenic HPV infections is also real. Even though cleared by the Food and Drug Administration and recommended by the World Federation for Ultrasound in Medicine and Biology, several disinfectants including glutaraldehyde and o-phthalaldehyde have shown a lack of efficacy for inactivating HPV. Other methods such as ultraviolet C and concentrated hydrogen peroxide have been shown highly effective at inactivating infectious HPV. In this study, two chlorine dioxide systems are also shown to be highly efficacious at inactivating HPV. An important difference in these present studies is that as opposed to testing in suspension or using a carrier, we dried the infectious virus directly onto endocavitary ultrasound probes and nasendoscopes, therefore, validating a more realistic system to demonstrate disinfectant efficacy.

The homeobox transcription factor HOXC13 upregulates human papillomavirus E1 gene expression and contributes to viral genome maintenance

Human papillomavirus (HPV) infects the basal cells of epithelia and maintains its genome stably as episomes. However, the mechanisms of viral genome maintenance are not fully understood. Here, using normal human immortalized keratinocytes (NIKS), we identified the homeobox transcription factor HOXC13 as a critical host factor for retaining the copy number of HPV genomes in the cell. HOXC13 knockdown in NIKS significantly decreased mRNA levels of the E1 gene, which encodes a DNA helicase required for HPV genome replication, accompanied by a reduction of the viral genome copy number. Chromatin immunoprecipitation assays revealed HOXC13 binding to the long control region that regulates E1 expression. These results indicate that HOXC13 plays invaluable roles in maintaining HPV persistent infection through E1 gene upregulation.

Transvaginal ultrasound probes are human papillomavirus-free following low-level disinfection: cross-sectional multicenter survey

OBJECTIVES

To assess the frequency of detection of high-risk human papillomavirus (hrHPV) on transvaginal ultrasound (TVS) probes and keyboards and evaluate operator compliance with national recommendations for prevention of cross-infection during TVS.

METHODS

This was a multicenter observational survey involving 46 public and private centers, in the Paris region of France, in which at least five consecutive TVS examinations were performed per day. We audited 676 TVS procedures. We recorded preventive hygiene actions undertaken by the operator at three stages: (1) during TVS; (2) during probe disinfection; and (3) during preparation of the probe for the next TVS. After probe disinfection, we collected one sample from the bare probe and one from the ultrasound keyboard; following probe preparation for the next examination, an additional sample was obtained from the covered probe. The samples were tested for presence of hrHPV DNA using the Cobas® 4800 System.

RESULTS

We did not detect hrHPV DNA in samples collected from uncovered or covered probes (0%; 95% CI, 0.00-0.55%). Keyboard samples were positive for hrHPV in two cases (0.3%; 95% CI, 0.04-1.07%). During TVS, the operator avoided touching the keyboard with a hand that had touched the patient's vulva in 86% of cases and held the probe with a gloved hand in 68%. Before probe disinfection, the operator wore new gloves, or performed hand disinfection in 8% of cases. The probe disinfection technique used was adequate in 87% of cases, not performed at all in 12% and insufficient in 1%. Before preparing the probe for the next scan, the operators disinfected their hands or used new gloves in 81% of cases. The probe cover and the coupling gel used complied with recommendations in 98% and 46% of cases, respectively. Of the seven preventive hygiene actions recommended in national guidelines, all were performed in 2%, three to six in 95% and two in 3% of observations. In four (9%) centers, disinfection was not performed in over half the observations.

CONCLUSIONS

No evidence of hrHPV DNA was found on TVS probes and probe covers following low-level disinfection, despite suboptimal compliance with hygiene guidelines. Routine TVS practice could be made easier and safer with a global approach to probe disinfection and hand hygiene. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Decontamination of Intravaginal Probes Infected by Human Papillomavirus (HPV) Using UV-C Decontamination System

Background: This three-step study evaluated ultraviolet-C (UV-C) efficacy against human papillomavirus (HPV) found on vaginal ultrasound probes. Methods: The first two steps evaluated UV-C disinfection of vaginal ultrasound probes in routine condition. During the first phase, the probe (n = 100) was sampled after a complete cleaning and disinfection protocol, i.e., cleaning with chemically impregnated wipes, followed by UV-C. During the second phase, the probe (n = 47) was sampled after cleaning and UV-C. The final step consisted of applying mixes of HPV on a dedicated, covered probe (n = 15) then sampling the cover, the probe after removal of the cover, after cleaning, and after UV-C. HPV detection was performed using CLART^® HPV2 PCR (Genomica, Madrid, Spain). Results: In the first phase, no probes were found to be positive for both DNA after UV-C. In the second phase, eight probes were found to be positive after cleaning (seven with human DNA and one with HPV) and negative after UV-C. In the final phase, one probe was found to be positive for HPV for each sample except after UV-C. Conclusions: Covers followed by a chemically impregnated wipe are not sufficient to ensure patient safety during vaginal ultrasound examinations. UV-C is effective in routine conditions against contaminations found on vaginal ultrasound probes, especially HPV.

Reprocessing semicritical items: Outbreaks and current issues

Semicritical medical devices are defined as items that come into contact with mucous membranes or nonintact skin (eg, gastrointestinal endoscopes, endocavitary probes). Such medical devices require minimally high-level disinfection. As many of these items are temperature sensitive, low-temperature chemical methods must be used rather than steam sterilization. Strict adherence to current guidelines is required as more outbreaks have been linked to inadequately cleaned or disinfected endoscopes and other semicritical items than any other reusable medical devices.

Reviewing the Use of Glutaraldehyde for High-level Disinfection by Sonographers

A review of recent literature has demonstrated that ultrasound transducers may harbor bacteria and viruses that could cause cross-contamination for patients. Reducing the risk of cross-contamination is achieved by high-level disinfection of ultrasound transducers. One of the main types of high-level disinfectants (HLD) used in performing sonography is glutaraldehyde (GA). While GA-based HLDs are cleared in abundance by the FDA and compatible with most transducers, GA has been reported to cause extensive adverse effects and has limited efficacy as a disinfectant. This literature review provides a current set of studies that discuss high-level disinfection of ultrasound transducers, GA use, exposure, and alternatives. This information could be used by practitioners to carefully consider how to effectively clean ultrasound transducers and supporting equipment. Additional guidance is provided on how to potentially minimize GA exposure and suggestions for protecting patients during their imaging examination.

Ultrasound probe use and reprocessing: Results from a national survey among U.S. infection preventionists

BACKGROUND

Improper infection prevention practice associated with ultrasound probe use has been linked to increased infection risk, outbreaks, and death. Although guidelines for reprocessing and use of probes exist, it is unclear how extensively these have been adopted in practice.

METHODS

Infection preventionists from U.S. health care facilities were surveyed (N = 358). The anonymous survey had 31 multiple choice, sliding scale, and text response questions. The survey was developed and deployed and the data were stored in the REDCap system.

RESULTS

A high degree of noncompliance with U.S. guidelines was identified. Surface probes used in invasive procedures were not high-level disinfected or sterilized 15% (intraoperative) to 78% (peripheral line placements) of the time. Of invasive procedures, 5%-47% did not use sterile gel (same procedures, respectively). Of the participants, 20% were aware of instances where an ultrasound probe was used but was not correctly reprocessed. Extensive breaches of infection control guidelines were reported. The rapid expansion in use of ultrasound has brought clinical benefit but may be exposing patients to preventable infection risk.

CONCLUSIONS

Infection preventionists are well placed to act as major drivers of change based on their expertise and experience in the management of infection risk across facilities and health systems. They, along with clinicians responsible for probe use and reprocessing, should review practices relating to ultrasound in their facilities. Where practice does not comply with guidelines, policy and training should be updated to ensure patient safety.

Development of an in vivo infection model to study Mouse papillomavirus-1 (MmuPV1)

Preclinical model systems to study multiple features of the papillomavirus life cycle are extremely valuable tools to aid our understanding of Human Papillomavirus (HPV) biology, disease progression and treatments. Mouse papillomavirus (MmuPV1) is the first ever rodent papillomavirus that can infect the laboratory strain of mice and was discovered recently in 2011. This model is an attractive model to study papillomavirus pathogenesis due to the ubiquitous availability of lab mice and the fact that this mouse species is easily genetically modifiable. Several other groups, including ours, have reported that MmuPV1-induced papillomas are restricted to T-cell deficient immunosuppressed mice. In our lab we showed for the first time that MmuPV1 causes skin cancers in UVB-irradiated immunocompetent animals. In this report we describe in detail the MmuPV1-UV infection model that can be adapted to study MmuPV1 biology in immunocompetent animals.

Infection prevention and control in ultrasound - best practice recommendations from the European Society of Radiology Ultrasound Working Group

OBJECTIVES

The objective of these recommendations is to highlight the importance of infection prevention and control in ultrasound (US), including diagnostic and interventional settings.

METHODS

Review of available publications and discussion within a multidisciplinary group consistent of radiologists and microbiologists, in consultation with European patient and industry representatives.

RECOMMENDATIONS

Good basic hygiene standards are essential. All US equipment must be approved prior to first use, including hand held devices. Any equipment in direct patient contact must be cleaned and disinfected prior to first use and after every examination. Regular deep cleaning of the entire US machine and environment should be undertaken. Faulty transducers should not be used. As outlined in presented flowcharts, low level disinfection is sufficient for standard US on intact skin. For all other minor and major interventional procedures as well as all endo-cavity US, high level disinfection is mandatory. Dedicated transducer covers must be used when transducers are in contact with mucous membranes or body fluids and sterile gel should be used inside and outside covers.

CONCLUSIONS

Good standards of basic hygiene and thorough decontamination of all US equipment as well as appropriate use of US gel and transducer covers are essential to keep patients safe.

MAIN MESSAGES

• Transducers must be cleaned/disinfected before first use and after every examination. • Low level disinfection is sufficient for standard US on intact skin. • High level disinfection is mandatory for endo-cavity US and all interventions. • Dedicated transducer covers must be used for endo-cavity US and all interventions. • Sterile gel should be used for all endo-cavity US and all interventions.

UVC radiation as an effective disinfectant method to inactivate human papillomaviruses

Endocavitary ultrasound probes are part of a commonly used procedure in the clinical arena. The cavities examined, vaginal canal and cervix, anal canal, and oral cavity are all areas commonly infected with the human papillomavirus (HPV), thus making them susceptible to contamination by HPV. It has been demonstrated that these probes can remain contaminated with high-risk HPV even when approved disinfection protocols have been performed. we have previously shown that HPV is resistant to some high-level disinfectant (HLD). In our present study we analyzed efficacy of using high-level ultra-violet C (UVC) radiation against HPV16 and HPV18 using a hard-surface carrier test. Stocks of infectious authentic HPV16 and HPV18 virions were dried onto carriers with a 5% (v/v) protein soil or 4ppm hard water. Efficacy testing were performed with the automated device, Antigermix S1 device (UVC radiation at 253.7nm) and 0.55% OPA in quadruplicate with matched input, neutralization, and cytotoxicity controls. Hypochlorite was included as a positive control for viral deactivation. Infectivity was determined by the abundance (qRT-PCR) of the spliced E1^E4 transcript in infected recipient cells. The automated Antigermix S1 device showed excellent efficacy against HPV16 and HPV18 whereas OPA showed minimal efficacy. While HPV is highly resistant to OPA, high-level UVC radiation offers an effective disinfection practice for ultrasound probes. Our results suggest that healthcare facilities using endocavitary ultrasound probes need to strongly consider disinfection methods that are effective against HPV.

Guidelines for Cleaning Transvaginal Ultrasound Transducers Between Patients

The purpose of this article is to provide guidance regarding the cleaning and disinfection of transvaginal ultrasound probes. These recommendations are also applicable to transrectal probes.

The wide spectrum high biocidal potency of Bioxy formulation when dissolved in water at different concentrations

Traditional surface disinfectants that have long been applied in medicine, animal husbandry, manufacturing and institutions are inconvenient at best and dangerous at worst. Moreover, some of these substances have adverse environmental impacts: for example, quaternary ammonium compounds ("quats") are reproductive toxicants in both fish and mammals. Halogens are corrosive both to metals and living tissues, are highly reactive, can be readily neutralized by metals, and react with organic matter to form toxic, persistent by-products such as dioxins and furans. Aldehydes may be carcinogenic to both human and animals upon repeated exposures, are corrosive, cross-link living tissues and many synthetic materials, and may lose efficacy when pathogens enzymatically adapt to them. Alcohols are flammable and volatile and can be enzymatically degraded by certain bacterial pathogens. Quats are highly irritating to mucous membranes and over time can induce pathogen resistance, especially if they are not alternated with functionally different disinfectants. In contrast, peracetic acid (PAA), a potent oxidizer, liberates hydrogen peroxide (itself a disinfectant), biodegrades to carbon dioxide, water and oxygen, and is at least as efficacious as contact biocides e.g., halogens and aldehydes. Nevertheless, the standard form of liquid PAA is highly corrosive, is neutralized by metals and organic matter, gives off noxious odours and must be stored in vented containers. For the reasons stated above, Bioxy formulations were developed, a series of powder forms of PAA, which are odourless, stable in storage and safe to transport and handle. They generate up to 10% PAA in situ when dissolved in water. A 0.2% aqueous solution of Bioxy (equivalent to 200 ppm PAA) effected a 6.76 log reduction in Methicillin-resistant Staphylococcus aureus (MRSA) within 2 minutes after application. A 5% aqueous solution of Bioxy achieved a 3.93 log reduction in the bovine tuberculosis bacillus Mycobacterium bovis, within 10 minutes after contact. A 1% solution of Bioxy reduced vancomycin-resistant enterococci (VRE) and Pseudomonas aeruginosa by 6.31 and 7.18 logs, respectively, within 3 minutes after application. A 0.5% solution of Bioxy inactivated porcine epidemic diarrhea virus (PEDV) within 15 minutes of contact, and a 5% solution of Bioxy realized a 5.36 log reduction in the spores of Clostridium difficile within 10 minutes of application. In summary, Bioxy is safe and easy to transport and store, poses negligible human, animal and environmental health risks, shows high levels of pathogen control efficacy and does not induce microbial resistance. Further investigations are recommended to explore its use as an industrial biocide.

Virucidal efficacy of a sonicated hydrogen peroxide system (trophon® EPR) following European and German test methods

Aim: The virucidal efficacy of an automated ultrasound probe disinfector (trophon^® EPR) was evaluated in a three step procedure according to European and German test methods. This system uses sonicated hydrogen peroxide mist (35%) at elevated temperature (50°C) in a closed chamber with control of all parameters within a 7 minute cycle. Methods: In the first step of examination, the peroxide solution was tested in a quantitative suspension assay according to the Guideline of Deutsche Vereinigung zur Bekämpfung der Viruskrankheiten (DVV) e.V. and Robert Koch-Institute (RKI) and in parallel with the European Norm EN 14476 with all test viruses creating a virucidal claim. In the second step, the virucidal efficacy of the hydrogen peroxide solution was evaluated in a hard surface carrier test according to the Guideline of DVV with adenovirus, murine norovirus and parvovirus simulating practical conditions. Finally, the efficacy was evaluated by the automated system using stainless steel carriers inoculated with test virus and positioned at different levels inside the chamber. Results: A ≥4 log₁₀ reduction of virus titre was demonstrated with all methods including carrier tests with murine norovirus, adenovirus, and parvovirus using the automated device. Conclusion: The automated device is able to inactivate test viruses of German and European norms and can therefore claim efficacy against human pathogenic enveloped and non-enveloped viruses. This includes human papillomaviruses which form part of the complete virucidal claim.

Disinfection and Sterilization in Health Care Facilities: An Overview and Current Issues

When properly used, disinfection and sterilization can ensure the safe use of invasive and noninvasive medical devices. The method of disinfection and sterilization depends on the intended use of the medical device: critical items (contact sterile tissue) must be sterilized before use; semicritical items (contact mucous membranes or nonintact skin) must be high-level disinfected; and noncritical items (contact intact skin) should receive low-level disinfection. Cleaning should always precede high-level disinfection and sterilization. Current disinfection and sterilization guidelines must be strictly followed.