Highly synergistic combinations of nanobodies that target SARS-CoV-2 reduce viral load in hACE2 transgenic mice

The ongoing emergence of SARS-CoV-2 variants threatens current vaccines and renders current therapeutic antibodies obsolete, demanding powerful new treatments that can resist viral escape. We therefore generated a large nanobody repertoire to saturate the distinct and highly conserved available epitope space of SARS-CoV-2 spike, including the S1 receptor binding domain, N-terminal domain, and the S2 subunit, to identify new nanobody binding sites that may reflect novel mechanisms of viral neutralization. Structural mapping and functional assays show that these highly stable monovalent nanobodies potently inhibit SARS-CoV-2 infection, display numerous neutralization mechanisms, are effective against past and present emerging variants of concern, and are resistant to mutational escape. Rational combinations of these nanobodies that bind dissimilar sites within and between spike subunits exhibit extraordinary synergy and suggest multiple tailored therapeutic and prophylactic strategies. All mouse involved experiments were performed in compliance with the Institutional Animal Care and Use Committee and mice were housed and maintained in a specific pathogen-free conditions at Seattle Children's Research Institute. Infected mice with SARSCoV- 2 were housed in a Biosafety Level 3 facility in an Animal Biohazard Containment Suite. Prophylactic intranasal application of a synergistic pair of unmodified nanobodies in 10-12 week-old female K18-hACE2 transgenic mice, a mouse model of SARS-CoV-2 infection, showed significant reduction in viral load after 3 days post-challenge with SARS-CoV-2, the first demonstration of synergy in vivo. In summary, our results show that our diverse repertoire of nanobodies can neutralize current variants of live SARS-CoV-2, pairs of nanobodies that bind distinct sites on spike show tremendous synergy in neutralizing efficacy in vitro, and the application of synergizing pair of nanobodies translates to an in vivo mouse model of SARSCoV- 2. Research funded by the Mathers Foundation, Robertson Foundation, NIH P41GM109824.Copyright © 2023 The American Society for Biochemistry and Molecular Biology, Inc.

Challenges in handling COVID-19 waste and its management mechanism: A Review.

COVID-19, the novel corona virus has become a household name. The global COVID-19 outbreak, become a pandemic in early 2020, and spurred millions of life across the world. The pandemic is spreading extremely and its impacts upon human health and environment intensifying day-by-day. Biomedical waste generated daily due to COVID-19 are about the major environmental health concern and its critical management becomes a global challenge. Tones of COVID-19 contaminated wastes are generated every day worldwide and its sound management is very essential to break the disease transmission. The safe and sustainable management of COVID-19 contaminated biomedical waste (BMW) is a social and legal responsibility of all people during this critical period of disease transmission. Unsound management of this waste could cause unforeseen "knock-on" effects on human health and the environment. Health workers, municipal workers, rag-pickers and other persons who are involved directly or indirectly in the COVID -19 war are at high risk and needs to be careful while discharging their responsibility with an efficient and effective waste disposal mechanism.

Experience of using an adapted snorkel mask as personal protective equipment in the COVID-19 pandemic

Introduction: During the COVID-19 pandemic and the cases of shortages of personal protective equipment (PPE), the utilization of modified snorkel masks has been documented, seeking to provide respiratory and facial pro-tection against SARS-CoV-2 aerosols. However, there is no report of changes in vital signs that can occur with its use, along with the perception of its wear by health personnel. Method(s): A case series was performed. Equipment: Snorkel mask, 3D adapter, and antimicrobial filter. CO2 level, respiratory rate, oximetry, pulse, and blood pressure were monitored for one hour. During the time of use, activities related to patient care were simulated. At the end, the usage characteristics were evaluated through a survey. Result(s): 14 volunteers were included in the study. After one hour of conti-nuous use, the clinical parameters were predominantly normal. 85% of the participants preferred this modified snorkel mask instead of personal protective equipment established for COVID-19 (goggles, N95 mask and visor). Conclusion(s): The adapted snorkel mask could be an alternative to PPE equipment in situations of scarce resources. This is only considered within the framework of its acceptability by a group of health professionals, in addition to the few effects on the vital signs evaluated in this case series. Further objective evaluations of usability and effectiveness are required. Copyright © 2023 Universidad de Antioquia.

Dental biosafety from pediatric dentists' perception in times of COVID-19, Lima, 2020

Objective: To describe pediatric dentists' perceptions regarding dental biosafety in times of COVID-19 in Lima, 2020. Material(s) and Method(s): A qualitative, phenomenological and content-analysis study. In-depth semi-structured interviews were conducted with 18 pediatric dentists through the Zoom videoconferencing platform, following the guidelines described in a guide and after obtaining the pertinent virtual informed consent. ATLAS.ti software version 8.4 was used for data analysis, where all the verbatim files of each interview were uploaded. Result(s): Pediatric dentists perceived themselves to be professionally empowered with knowledge about biosafety measures. Moreover, they highlighted the mastery of various techniques such as mouthwash, use of personal protective equipment, control of aerosols, social distancing between patients and disinfection of environments, which are essential for patient safety. They also reported that biosafety regulations are somewhat confusing, unclear, and lack a pediatric approach. Conclusion(s): Pediatric dentists are strategic human resources for healthcare because they gained biosafety knowledge as part of their professional education and received training on new biosafety regulations in the context of the COVID-19 pandemic. It is important to standardize the criteria and approaches in the model of care for pediatric dentistry and guarantee the conditions for the sustainability of this professional practice. Copyright © La revista.

Personal protective equipment in dental care during covid-19. A review

COVID-19 evidenced the need for preventive protocols to control its spread worldwide. Therefore, the purpose of this review was to compare the current indications and regulations for the use of personal protective equipment (PPE) in dental care. For the bibliographic search, keywords such as "Containment of Biohazards", "Personal Protective Equipment", "dental office", "COVID-19" were used during the advanced search in Pubmed and academic Google. Forty regulations were obtained that met all the selection criteria for preventive measures through the use of PPE by the operator and the patient;being more detailed the Sanitary Directive 100-MINSA published in 2020 without evidence of updating in this year 2021. Likewise, in studies carried out on the reuse of masks, it was determined that the most effective method was decontamination with UV-C, which maintains their integrity and filtering capacity. Copyright © 2022 Universidad Peruana Cayetano Heredia, Facultad de Medicina Alberto Hurtado

Self-report on COVID-19: a survey of paraguayan dentists / Autorreporte acerca del contagio de COVID-19: una encuesta a odontólogos paraguayos

Aim: To determine the frequency of signs and/or symptoms compatible with COVID-19 in Paraguayan dentists, as well as the possible source of contagion. Material and Methods: Online survey consisting of 13 questions, applied to all dentists in Paraguay from January 20 to February 15, 2021. Results: A total of 433 dentists participated in the survey; 47.5% displayed symptoms compatible with COVID-19 and 13.39% indicated that they had contracted the disease, providing confirmation via a positive test result. Headache, loss of smell, loss of taste, cough, and fatigue were the most prevalent symptoms among COVID-19 positive cases. The main source of contagion was the family nucleus. Only one participant reported having contracted the disease while providing dental care. Conclusion: Almost half of the dentists displayed symptoms compatible with COVID-19. Only 13.39% tested positive for COVID-19. Only one case of contagion was reported to have happened during the provision of dental care.

Evaluation of risk levels due to exposure to biological agents during the process of collecting household urban solid waste

The purpose of this study was to evaluate the levels of risk due to exposure to biological agents in the activity of wa ste collectors working in an organization dedicated to the private collection of household solid urban waste in Ecuador. The BIOGAVAL-NEO 2018 method proposed by the Instituto Valencia de Seguridad y Salud en el Trabajo (INVASSAT) for the evaluation of biological risk in various work activities was applied. This method observes the determination of the job to be assessed, the identification of the biological agent involved, quantification of the variables determining the risk, hygiene measures adopted, calculation of the level of biological risk and interpretation of the levels of biological risk. This is a cross-sectional, descriptive study. From the results obtained in the present study after applying the BIOGAVAL-NEO 2018 method, it was found that the biological risk level (R) for the most common biological agents in this activity were: leptospira interrogans, hepatitis A virus, hepatitis B virus and SARS-CoV-2, being equal to and above the biological action level (BAC), and below the biological exposure limit level (BEL). The applied BIOGAVAL-NEO 2018 quantification method is a practical and highly useful tool with priority orientation of hygienic and biosafety measures allowing to reduce the level of biological risk in collectors during the household solid urban waste collection process in Ecuador. © 2022 Latin American and Caribbean Consortium of Engineering Institutions. All rights reserved.

IACUC and Veterinary Considerations for Review of ABSL3 and ABSL4 Research Protocols.

With the recent upswing of infectious disease outbreaks (coronavirus, influenza, Ebola, etc), there is an ever-increasing need for biocontainment animal use protocols to better address the research of emerging diseases and to increase the health of both animals and humans. It is imperative that we as a research community ensure these protocols are conducted with the utmost scrutiny and regulatory compliance for the welfare of the animals as well as the health and safety concerns of the individual conducting these studies. Both the welfare of the animals and the health and safety of the research staff must be balanced with the integrity of the science being studied. Even prior to reviewing biocontainment protocols, the research stakeholders should have professional and collegial interactions across all levels of the proposed project. These stakeholders should include the attending veterinarian, the principal investigator, the sponsor, and any organic institutional health and safety assets (environmental health and safety, occupational health, biosafety personnel, medical personnel, facilities operations and maintenance, etc). At most institutions, these stakeholders are members of the Institutional Animal Care and Use Committee and may not possess the necessary tools to properly assess an Animal Biosafety Level 3 and 4 animal use protocol. It is the goal of this article to review some basic concepts of biocontainment, discuss critical communications and preapprovals, clinical observations, medical interventions and supportive care, scientific and study endpoints, euthanasia criteria, animal manipulations, documentation, training, emergency response and contingency plans, security, and decontamination and provide a scenario-based and informative thought-provoking process Institutional Animal Care and Use Committee members and veterinary staff may consider during Animal Biosafety Level 3 and 4 protocol review. These topics will enhance the ability of all stakeholders to balance the protection of the people with the integrity of the science and ultimately the welfare of the animal.

Knowledge of odontologists on biosafety in times of COVID-19

Objective: to describe the level of knowledge of odontologists about biosafety in the face of COVID-19 and identify its relationship with variables of interest. Research about dental biosecurity against COVID-19 has become specially important at present that offer guidelines and allow us to compare the behavoiur of this phenomenon in different centers. Material and methods: it is a descriptive and cross-sectional observational research in the cuban odontological services of Mella municipality in Santiago de Cuba province in November 2020. The population consisted of dentists and a sample of 40 dentists was selected. Variables such as profesional occupation, years of graduation and level of knowledge on biosafety, which was identified as adequate, moderately adequate and inadequate, according to the surveys applied. Results: in the first three items evaluated, the level of inadequate knowledge predominated (50% on general measures, 47.5 % on hand hygiene, and 40 % on personal protection);in medium grade, the use of jewelry and care of environment with 50 and 75 % respectively;in addition there were no statistically significant differences between the level of knowledge, professional occupation and years of graduation. Conclusions: the level of knowledge of odontologists about biosafety in the face of COVID-19 is moderately adequate and does not depend on their level of specialization or professional experience.

Environmental Surveillance and Transmission Risk Assessments for SARS-CoV-2 in a Fitness Center.

Fitness centers are considered high risk for SARS-CoV-2 transmission due to their high human occupancy and the type of activity taking place in them, especially when individuals pre-symptomatic or asymptomatic for COVID-19 exercise in the facilities. In this study, air (N=21) and surface (N=8) samples were collected at a fitness center through five sampling events from August to November 2020 after the reopening restrictions were lifted in Florida. The total attendance was ~2500 patrons during our air and environmental sampling work. Air samples were collected using stationary and personal bioaerosol samplers. Moistened flocked nylon swabs were used to collect samples from high-touch surfaces. We did not detect SARS-CoV-2 by rRT-PCR analyses in any air or surface sample. A simplified infection risk model based on the Wells-Riley equation predicts that the probability of infection in this fitness center was 1.77% following its ventilation system upgrades based on CDC guidelines, and that risk was further reduced to 0.89% when patrons used face masks. Our model also predicts that a combination of high ventilation, minimal air recirculation, air filtration, and UV sterilization of recirculated air reduced the infection risk up to 94% compared to poorly ventilated facilities. Amongst these measures, high ventilation with outdoor air is most critical in reducing the airborne transmission of SARS-CoV-2. For buildings that cannot avoid air recirculation due to energy costs, the use of high filtration and/or air disinfection devices are alternatives to reducing the probability of acquiring SARS-CoV-2 through inhalation exposure. In contrast to the perceived ranking of high risk, the infection risk in fitness centers that follow CDC reopening guidance, including implementation of engineering and administrative controls, and use of personal protective equipment, can be low, and these facilities can offer a relatively safe venue for patrons to exercise.

Lessons Learned From a COVID-19 Biohazard Spill During Swabbing at a Quarantine Facility.

The need for increased testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), has resulted in an increase of testing facilities outside of traditional clinical settings and sample handling by individuals without appropriate biohazard and biocontainment training. During the repatriation and quarantine of passengers from the Grand Princess cruise ship at a US military base, biocontainment of a potentially infectious sample from a passenger was compromised. This study describes the steps taken to contain the spill, decontaminate the area, and discusses the needs for adequate training in a biohazard response.

Operational considerations and challenges of biochemistry laboratories during the COVID-19 outbreak: an IFCC global survey.

Objectives: The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Task Force on COVID-19 conducted a global survey to understand how biochemistry laboratories manage the operational challenges during the coronavirus disease 2019 (COVID-19) pandemic. Materials and methods: An electronic survey was distributed globally to record the operational considerations to mitigate biosafety risks in the laboratory. Additionally, the laboratories were asked to indicate the operational challenges they faced. Results: A total of 1210 valid submissions were included in this analysis. Most of the survey participants worked in hospital laboratories. Around 15% of laboratories restricted certain tests on patients with clinically suspected or confirmed COVID-19 over biosafety concerns. Just over 10% of the laboratories had to restrict their test menu or services due to resource constraints. Approximately a third of laboratories performed temperature monitoring, while two thirds of laboratories increased the frequency of disinfection. Just less than 50% of the laboratories split their teams. The greatest reported challenge faced by laboratories during the COVID-19 pandemic is securing sufficient supplies of personal protective equipment (PPE), analytical equipment, including those used at the point of care, as well as reagents, consumables and other laboratory materials. This was followed by having inadequate staff, managing their morale, anxiety and deployment. Conclusions: The restriction of tests and services may have undesirable clinical consequences as clinicians are deprived of important information to deliver appropriate care to their patients. Staff rostering and biosafety concerns require longer-term solutions as they are crucial for the continued operation of the laboratory during what may well be a prolonged pandemic.

Laboratory practices to mitigate biohazard risks during the COVID-19 outbreak: an IFCC global survey.

Objectives: A global survey was conducted by the IFCC Task Force on COVID-19 to better understand how general biochemistry laboratories manage the pre-analytical, analytical and post-analytical processes to mitigate biohazard risks during the coronavirus disease 2019 (COVID-19) pandemic. Methods: An electronic survey was developed to record the general characteristics of the laboratory, as well as the pre-analytical, analytical, post-analytical and operational practices of biochemistry laboratories that are managing clinical samples of patients with COVID-19. Results: A total of 1210 submissions were included in the analysis. The majority of responses came from hospital central/core laboratories that serve hospital patient groups and handle moderate daily sample volumes. There has been a decrease in the use of pneumatic tube transport, increase in hand delivery and increase in number of layers of plastic bags for samples of patients with clinically suspected or confirmed COVID-19. Surgical face masks and gloves are the most commonly used personal protective equipment (PPE). Just >50% of the laboratories did not perform an additional decontamination step on the instrument after analysis of samples from patients with clinically suspected or confirmed COVID-19. A fifth of laboratories disallowed add-on testing on these samples. Less than a quarter of laboratories autoclaved their samples prior to disposal. Conclusions: The survey responses showed wide variation in pre-analytical, analytical and post-analytical practices in terms of PPE adoption and biosafety processes. It is likely that many of the suboptimal biosafety practices are related to practical local factors, such as limited PPE availability and lack of automated instrumentation.

Intubation Containment System for Improved Protection From Aerosolized Particles During Airway Management.

OBJECTIVES: Worldwide efforts to protect front line providers performing endotracheal intubation during the COVID-19 pandemic have led to innovative devices. Authors evaluated the aerosol containment effectiveness of a novel intubation aerosol containment system (IACS) compared with a recently promoted intubation box and no protective barrier. METHODS: In a simulation center at the authors' university, the IACS was compared to no protective barrier and an intubation box. Aerosolization was simulated using a commercial fog machine and leakage of aerosolize mist was visually assessed. RESULTS: The IACS appeared to contain the aerosolized mist, while the intubation box allowed for mist to contact the laryngoscopist and contaminate the clinical space through arm port holes and the open caudal end. Both devices protected the laryngoscopist better than no protective barrier. DISCUSSION: The IACS with integrated sleeves and plastic drape appears to offer superior protection for the laryngoscopist and assistant providers from aerosolized particles.