Anesthesia and Critical Care for the Prediction and Prevention for Small-for-size Syndrome: Guidelines from the ILTS-iLDLT-LTSI Consensus Conference.

BACKGROUND: During the perioperative period of living donor liver transplantation, anesthesiologists and intensivists may encounter patients in receipt of small grafts that puts them at risk of developing small for size syndrome (SFSS). METHODS: A scientific committee (106 members from 21 countries) performed an extensive literature review on aspects of SFSS with proposed recommendations. Recommendations underwent a blinded review by an independent expert panel and discussion/voting on the recommendations occurred at a consensus conference organized by the International Liver Transplantation Society, International Living Donor Liver Transplantation Group, and Liver Transplantation Society of India. RESULTS: It was determined that centers with experience in living donor liver transplantation should utilize potential small for size grafts. Higher risk recipients with sarcopenia, cardiopulmonary, and renal dysfunction should receive small for size grafts with caution. In the intraoperative phase, a restrictive fluid strategy should be considered along with routine use of cardiac output monitoring, as well as use of pharmacologic portal flow modulation when appropriate. Postoperatively, these patients can be considered for enhanced recovery and should receive proactive monitoring for SFSS, nutrition optimization, infection prevention, and consideration for early renal replacement therapy for avoidance of graft congestion. CONCLUSIONS: Our recommendations provide a framework for the optimal anesthetic and critical care management in the perioperative period for patients with grafts that put them at risk of developing SFSS. There is a significant limitation in the level of evidence for most recommendations. This statement aims to provide guidance for future research in the perioperative management of SFSS.

Mainstreaming adult ADHD into primary care in the UK: guidance, practice, and best practice recommendations.

BACKGROUND: ADHD in adults is a common and debilitating neurodevelopmental mental health condition. Yet, diagnosis, clinical management and monitoring are frequently constrained by scarce resources, low capacity in specialist services and limited awareness or training in both primary and secondary care. As a result, many people with ADHD experience serious barriers in accessing the care they need. METHODS: Professionals across primary, secondary, and tertiary care met to discuss adult ADHD clinical care in the United Kingdom. Discussions identified constraints in service provision, and service delivery models with potential to improve healthcare access and delivery. The group aimed to provide a roadmap for improving access to ADHD treatment, identifying avenues for improving provision under current constraints, and innovating provision in the longer-term. National Institute for Health and Care Excellence (NICE) guidelines were used as a benchmark in discussions. RESULTS: The group identified three interrelated constraints. First, inconsistent interpretation of what constitutes a 'specialist' in the context of delivering ADHD care. Second, restriction of service delivery to limited capacity secondary or tertiary care services. Third, financial limitations or conflicts which reduce capacity and render transfer of care between healthcare sectors difficult. The group recommended the development of ADHD specialism within primary care, along with the transfer of routine and straightforward treatment monitoring to primary care services. Longer term, ADHD care pathways should be brought into line with those for other common mental health disorders, including treatment initiation by appropriately qualified clinicians in primary care, and referral to secondary mental health or tertiary services for more complex cases. Long-term plans in the NHS for more joined up and flexible provision, using a primary care network approach, could invest in developing shared ADHD specialist resources. CONCLUSIONS: The relegation of adult ADHD diagnosis, treatment and monitoring to specialist tertiary and secondary services is at odds with its high prevalence and chronic course. To enable the cost-effective and at-scale access to ADHD treatment that is needed, general adult mental health and primary care must be empowered to play a key role in the delivery of quality services for adults with ADHD.

A Switchable Palladium(II) Trefoil Entangled Tetrahedron with Temperature Dependence and Concentration Independence.

Self-assembly makes metallo-interlocked architectures attractive targets, but being in equilibrium with smaller species means that they can suffer from dilution effects. We show that a junctioned system gives rise to a [Pd4 (L)2 ]8+ trefoil entangled tetrahedron irrespective of concentration. Heating the sample reversibly shifts the equilibrium from the knot to an isomeric non-interlocked dual metallo-cycle, demonstrating that thermodynamic equilibria can still be exploited for switching even in the absence of concentration effects.

Histopathological and Immunological Findings in the Common Marmoset Following Exposure to Aerosolized SARS-CoV-2.

There is an enduring requirement to develop animal models of COVID-19 to assess the efficacy of vaccines and therapeutics that can be used to treat the disease in humans. In this study, six marmosets were exposed to a small particle aerosol (1-3 µm) of SARS-CoV-2 VIC01 that delivered the virus directly to the lower respiratory tract. Following the challenge, marmosets did not develop clinical signs, although a disruption to the normal diurnal temperature rhythm was observed in three out of six animals. Early weight loss and changes to respiratory pattern and activity were also observed, yet there was limited evidence of viral replication or lung pathology associated with infection. There was a robust innate immunological response to infection, which included an early increase in circulating neutrophils and monocytes and a reduction in the proportion of circulating T-cells. Expression of the ACE2 receptor in respiratory tissues was almost absent, but there was ubiquitous expression of TMPRSS2. The results of this study indicate that exposure of marmosets to high concentrations of aerosolised SARS-CoV-2 did not result in the development of clear, reproducible signs of COVID-19.

Heteroleptic Tripalladium(II) Cages.

There is a concerted attempt to develop self-assembled metallo-cages of greater structural complexity, and heteroleptic PdII cages are emerging as prime candidates in these efforts. Most of these are dinuclear: few examples of higher nuclearity have been reported. We demonstrate here a robust method for the formation of tripalladium(II) cages from the 2 : 3 : 3 combination of a tritopic ligand, PdII , and a selection of ditopic ligands of the correct size and geometry.

Optimal anesthetic conduct regarding immediate and short-term outcomes after liver transplantation - Systematic review of the literature and expert panel recommendations.

BACKGROUND: In the era of enhanced recovery after surgery, there is significant discussion regarding the impact of intraoperative anesthetic management on short-term outcomes following liver transplantation (LT), with no clear consensus in the literature. OBJECTIVES: To identify whether or not intraoperative anesthetic management affects short-term outcomes after liver transplantation. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: A systematic review following PRISMA guidelines was undertaken. The systematic review was registered on PROSPERO (CRD42021239758). An international expert panel made recommendations for clinical practice using the GRADE approach. RESULTS: After screening, 14 studies were eligible for inclusion in this systematic review. Six were prospective randomized clinical trials, three were prospective nonrandomized clinical trials, and five were retrospective studies. These manuscripts were reviewed to look at five questions regarding anesthetic care and its impact on short term outcomes following liver transplant. After review of the literature, the quality of evidence according to the following outcomes was as follows: intraoperative and postoperative morbidity and mortality (low), early allograft dysfunction (low), and hospital and ICU length of stay (moderate). CONCLUSIONS: For optimal short term outcomes after liver transplantation, the panel recommends the use of volatile anesthetics in preference to total intravenous anesthesia (TIVA) (Level of Evidence: Very low; Strength of Recommendation: Weak) and minimum alveolar concentration (MAC) versus bispectral index (BIS) for depth of anesthesia monitoring (Level of Evidence: Very low; Strength of Recommendation: Weak). Regarding ventilation and oxygenation, the panel recommends a restrictive oxygenation strategy targeting a PaO2 of 70-120 mmHg (10-14 kPa), a tidal volume of 6-8 ml/kg ideal body weight (IBW), administration of positive end expiratory pressure (PEEP) tailored to patient intraoperative physiology, and recruitment maneuvers. (Level of evidence: Very low; Strength of Recommendation: Strong). Finally, the panel recommends the routine use of antiemetic prophylaxis. (Level of evidence: low; Strength of Recommendation: Strong).

Roles of Metal Ions in Foldamers and Other Conformationally Flexible Supramolecular Systems.

Conformational control is a key prerequisite for much molecular function. As chemists seek to create complex molecules that have applications beyond the academic laboratory, correct spatial positioning is critical. This is particularly true of flexible systems. Conformationally flexible molecules show potential because they resemble in many cases naturally occurring analogues such as the secondary structures found in proteins and peptides such as α-helices and ß-sheets. One of the ways in which conformation can be controlled in these molecules is through interaction with or coordination to metal ions. This review explores how secondary structure (i.e., controlled local conformation) in foldamers and other conformationally flexible systems can be enforced or modified through coordination to metal ions. We hope to provide examples that illustrate the power of metal ions to influence this structure toward multiple different outcomes.

Corrigendum: Evaluation of the SARS-CoV-2 Inactivation Efficacy Associated With Buffers From Three Kits Used on High-Throughput RNA Extraction Platforms.

[This corrects the article DOI: 10.3389/fcimb.2021.716436.].

The Success of a Simulation-Based Transesophageal Echocardiography Course for Liver Transplant Anesthesiologists.

INTRODUCTION: Transesophageal echocardiography (TEE) is increasingly used for intraoperative management during orthotopic liver transplantation. Proficient TEE use requires skill and knowledge to accurately assess the hemodynamic status and guide clinical management. Currently there are no TEE educational tracks specifically focused on perioperative liver transplant management and barriers to obtaining basic certification exist. METHODS: A 4-hour simulation-based learning (SBL) course was provided to improve liver transplant anesthesiologist TEE knowledge and skill. Learners received training and education using a TEE simulator in small groups focusing on basic image acquisition, relevant anatomy, hemodynamic calculations, and pathology germane to the liver transplant period. Knowledge assessment and survey responses were assessed at the beginning and completion of the course. Learners completed TEE examinations with simulated pathology during high-fidelity simulations following the course. RESULTS: Seventeen anesthesiologists completed the course. The median baseline knowledge assessment score was 55.0% (37-70). The median postcourse knowledge assessment score improved to 95.0% (94-100) (P < .001). All anesthesiologists were able to identify TEE pathology during high-fidelity simulation. Survey responses yielded significant median score improvement in all areas assessed using a 5-point Likert scale. CONCLUSIONS: A small group, simulation TEE course delivered over 4 hours can increase knowledge and skill in TEE use for liver transplant anesthesiologists.

Can 2-Pyridyl-1,2,3-triazole "Click" Ligands be Used to Develop Cu(I)/Cu(II) Molecular Switches?

Molecular switching processes are important in a range of areas including the development of molecular machines. While there are numerous organic switching systems available, there are far less examples that exploit inorganic materials. The most common inorganic switching system remains the copper(I)/copper(II) switch developed by Sauvage and co-workers over 20 years ago. Herein, we examine if bidentate 2-(1-benzyl-1H-1,2,3-triazol-4-yl)pyridine (pytri) and tridentate 2,6-bis[(4-phenyl-1H-1,2,3-triazol-1-yl)methyl]pyridine (tripy) moieties can be used to replace the more commonly exploited polypyridyl ligands 2,2'-bypyridine (bpy)/1,10-phenanthroline (phen) and 2,2';6',2″-terpyridine (terpy) in a copper(I)/(II) switching system. Two new ditopic ligands that feature bidentate (pytri, L1 or bpytri, L2) and tridentate tripy metal binding pockets were synthesized and used to generate a family of heteroleptic copper(I) and copper(II) 6,6'-dimesityl-2,2'-bipyridine (diMesbpy) complexes. Additionally, we synthesized a series of model copper(I) and copper(II) diMesbpy complexes. A combination of techniques including nuclear magnetic resonance (NMR) and UV-vis spectroscopies, high-resolution electrospray ionization mass spectrometry, and X-ray crystallography was used to examine the behavior of the compounds. It was found that L1 and L2 formed [(diMesbpy)Cu(L1 or L2)]2+ complexes where the copper(II) diMesbpy unit was coordinated exclusively in the tridenate tripy binding site. However, when the ligands (L1 and L2) were complexed with copper(I) diMesbpy units, a complex mixture was obtained. NMR and MS data indicated that a 1:1 stoichiometry of [Cu(diMesbpy)]+ and either L1 or L2 generated three complexes in solution, the dimetallic [(diMesbpy)2Cu2(L1 or L2)]2+ and the monometallic [(diMesbpy)Cu(L1 or L2)]+ isomers where the [Cu(diMesbpy)]+ unit is coordinated to either the bidentate or tridentate tripy binding sites of the ditopic ligands. The dimetallic [(diMesbpy)2Cu2(L1 or L2)](PF6)2 complexes were structurally characterized using X-ray crystallography. Both complexes feature a [Cu(diMesbpy)]+ coordinated to the bidentate (pytri or bpytri) pocket of the ditopic ligands (L1 or L2), as expected. They also feature a second [Cu(diMesbpy)]+ coordinated to the nominally tridentate tripy binding site in a four-coordinate hypodentate κ2-fashion. Competition experiments with model complexes showed that the binding strength of the bidentate pytri is similar to that of the κ2-tripy ligand, leading to the lack of selectivity. The results suggest that the pytri/tripy and bpytri/tripy ligand pairs cannot be used as replacements for the more common bpy/phen-terpy partners due to the lack of selectivity in the copper(I) state.

Evaluation of the SARS-CoV-2 Inactivation Efficacy Associated With Buffers From Three Kits Used on High-Throughput RNA Extraction Platforms.

Rapid and demonstrable inactivation of SARS-CoV-2 is crucial to ensure operator safety during high-throughput testing of clinical samples. The inactivation efficacy of SARS-CoV-2 was evaluated using commercially available lysis buffers from three viral RNA extraction kits used on two high-throughput (96-well) RNA extraction platforms (Qiagen QIAcube HT and the Thermo Fisher KingFisher Flex) in combination with thermal treatment. Buffer volumes and sample ratios were chosen for their optimised suitability for RNA extraction rather than inactivation efficacy and tested against a representative sample type: SARS-CoV-2 spiked into viral transport medium (VTM). A lysis buffer mix from the MagMAX Pathogen RNA/DNA kit (Thermo Fisher), used on the KingFisher Flex, which included guanidinium isothiocyanate (GITC), a detergent, and isopropanol, demonstrated a minimum inactivation efficacy of 1 × 105 tissue culture infectious dose (TCID)50/ml. Alternative lysis buffer mixes from the MagMAX Viral/Pathogen Nucleic Acid kit (Thermo Fisher) also used on the KingFisher Flex and from the QIAamp 96 Virus QIAcube HT Kit (Qiagen) used on the QIAcube HT (both of which contained GITC and a detergent) reduced titres by 1 × 104 TCID50/ml but did not completely inactivate the virus. Heat treatment alone (15 min, 68°C) did not completely inactivate the virus, demonstrating a reduction of 1 × 103 TCID50/ml. When inactivation methods included both heat treatment and addition of lysis buffer, all methods were shown to completely inactivate SARS-CoV-2 inactivation against the viral titres tested. Results are discussed in the context of the operation of a high-throughput diagnostic laboratory.

Investigative study into whether an insect repellent has virucidal activity against SARS-CoV-2.

A small-scale study with Mosi-guard Natural spray, an insect repellent containing Citriodiol, was performed to determine if it has virucidal activity against SARS-CoV-2. A liquid test examined the activity of the insect repellent and the individual components for virucidal activity. A surface contact test looked at the activity of the insect repellent when impregnated on a latex surface as a synthetic skin for potential topical prophylactic application. Both Mosi-guard Natural spray and Citriodiol, as well as other components of the repellent, had virucidal activity in the liquid contact test. On a latex surface used to simulate treated skin, the titre of SARS-CoV-2 was less over time on the Mosi-guard Natural-treated surface but virus was still recovered.

The perioperative management of simultaneous bilateral nephrectomy with renal transplantation: a case series.

PURPOSE: Bilateral nephrectomy is performed at times with renal transplantation. Though surgical indications and timing of these two procedures have been described, there are no large case series describing the anesthetic management of these cases. We sought to describe our experience. METHODS: We performed a historical cohort study on 54 consecutive cases of simultaneous bilateral nephrectomy with renal transplantation at a single, tertiary-care medical centre. Descriptive statistics were used. RESULTS: The most common etiology of kidney disease involved was autosomal dominant polycystic kidney disease at 52/54 (96%) cases. All patients received grafts from living donors. An arterial line was placed in 44 (81%) and a central venous catheter in 16 (30%) subjects. At least one vasopressor infusion was used in 44 (81%) cases and 37 (69%) patients required admission to the intensive care unit (ICU). Of this subset, 30 (81%) were admitted for ongoing vasopressor support and six (16%) for hemodynamic monitoring. All patients were extubated in the operating room upon completion of the procedure. Median [interquartile range (IQR)] ICU length of stay (LOS) was 0.9 [0.7-1.4] days and total hospital LOS was 4.4 [4.3-5.4] days. There were no cases of mortality at 30 days or of postoperative dialysis. CONCLUSIONS: Adult patients undergoing simultaneous bilateral nephrectomy with renal transplantation often developed perioperative hypotension requiring vasopressor infusions and postoperative transfer to the ICU. This is possibly due to a temporary loss of the renin-angiotensin system. Despite this, patients most commonly were transferred to the floor on postoperative day 1 and had successful outcomes with no mortality at 30 days.

RéSUMé: OBJECTIF: La néphrectomie bilatérale est parfois réalisée en même temps qu'une transplantation rénale. Bien que les indications chirurgicales et le moment de ces deux interventions aient été décrits, il n'existe aucune grande série de cas décrivant la prise en charge anesthésique de ces procédures. Notre objectif était de décrire notre expérience. MéTHODE: Nous avons réalisé une étude de cohorte historique sur 54 cas consécutifs de néphrectomie bilatérale avec transplantation rénale simultanée dans un seul centre médical de soins tertiaires. Des statistiques descriptives ont été utilisées. RéSULTATS: La maladie polykystique des reins autosomique dominante constituait l'étiologie de la maladie rénale la plus fréquente, représentant 52/54 (96 %) des cas. Tous les patients ont reçu des greffes de donneurs vivants. Une ligne artérielle a été installée chez 44 (81 %) patients et un cathéter veineux central chez 16 (30 %) patients. Au moins une perfusion de vasopresseurs a été utilisée chez 44 (81 %) patients, et 37 (69 %) patients ont dû être admis à l'unité de soins intensifs (USI). De ce sous-ensemble, 30 (81 %) patients ont été admis pour recevoir un soutien continu de vasopresseurs et six (16 %) pour un monitorage hémodynamique. Tous les patients ont été extubés en salle d'opération à la fin de l'intervention. La durée médiane [écart interquartile (ÉIQ)] de séjour aux soins intensifs était de 0,9 [0,7 à 1,4] jour, et la durée totale de séjour à l'hôpital était de 4,4 [4,3 à 5,4] jours. Il n'y a eu aucun cas de mortalité à 30 jours ou de dialyse postopératoire. CONCLUSION: Les patients adultes subissant une néphrectomie bilatérale et une transplantation rénale simultanées ont souvent souffert d'hypotension périopératoire exigeant des perfusions de vasopresseurs et un transfert postopératoire aux soins intensifs. Ceci est probablement dû à une perte temporaire du système rénine-angiotensine. Malgré cela, les patients étaient en général transférés à l'étage au jour postopératoire 1 et ont eu des devenirs favorables sans mortalité à 30 jours.

When Is a Critically Ill Cirrhotic Patient Too Sick to Transplant? Development of Consensus Criteria by a Multidisciplinary Panel of 35 International Experts.

BACKGROUND: Critically ill cirrhotic patients are increasingly transplanted, but there is no consensus about futile liver transplantation (LT). Therefore, the decision to delay or deny LT is often extensively debated. These debates arise from different opinions of futility among transplant team members. This study aims to achieve a multinational and multidisciplinary consensus on the definition of futility in LT and to develop well-articulated criteria for not proceeding with LT due to futility. METHODS: Thirty-five international experts from anesthesiology/intensive care, hepatology, and transplant surgery were surveyed using the Delphi method. More than 70% of similar answers to a question were necessary to define agreement. RESULTS: The panel recommended patient and graft survival at 1 year after LT to define futility. Severe frailty and persistent fever or <72 hours of appropriate antimicrobial therapy in case of ongoing sepsis were considered reasons to delay LT. A simple assessment of the number of organs failing was considered the most appropriate way to decide whether LT should be delayed or denied, with respiratory, circulatory and metabolic failures having the most influence in this decision. The thresholds of severity of organ failures contraindicating LT for which a consensus was achieved were a Pao2/FiO2 ratio<150 mm Hg, a norepinephrine dose >1 µg/kg per minute and a serum lactate level >9 mmol/L. CONCLUSIONS: Our expert panel provides a consensus on the definition of futile LT and on specific criteria for postponing or denying LT. A framework that may facilitate the decision if a patient is too sick for transplant is presented.

Self-Assembly of a Redox Active, Metallosupramolecular [Pd3 L6 ]6+ Complex Using a Rotationally Flexible Ferrocene Ligand.

A new ferrocene-containing [Pd3 (L4EFc )6 ]6+ (X- )6 (C ⋅ BF4 and C ⋅ SbF6 where X=BF4 - or SbF6 - ) self-assembled double-walled triangle has been synthesized from the known, rotationally flexible, 1,1'-bis(4-pyridylethynyl)ferrocene ligand (L4EFc ), and characterized by 1 H, 13 C and diffusion ordered (DOSY) NMR spectroscopies, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), X-ray crystallography and cyclic voltammetry (CV). The molecular structures confirmed that double-walled triangle cage systems (C ⋅ BF4 and C ⋅ SbF6 ) were generated. C ⋅ BF4 was shown to interact with the anionic guest, p-toluenesulfonate. CV experiments revealed that the triangles were redox active, however addition of the guest did not influence the redox potentials.

Outcomes of Liver Transplantation in Treated Portopulmonary Hypertension Patients With a Mean Pulmonary Arterial Pressure ≥35 mm Hg.

Portopulmonary hypertension (POPH), pulmonary arterial hypertension (PAH) that develops in the setting of portal hypertension, affects 5%-6% of patients with liver disease and is associated with significant morbidity and mortality. A mean pulmonary arterial pressure (mPAP) threshold of 35 mm Hg is used to stratify perioperative risk and liver transplant eligibility in treated POPH patients but does not take into account the specific factors that contribute to the pressure elevation. METHODS: In this case series, we describe the characteristics and posttransplant outcomes of patients with treated POPH and an mPAP ≥35 mm Hg and pulmonary vascular resistance (PVR) <250 dynes-s-cm-5 at or just before liver transplantation (LT). We also describe the effect of PAH therapy on pulmonary hemodynamics in patients with POPH. RESULTS: Sixteen patients were included. All patients were on PAH therapy at the time of LT. PAH therapy resulted in a decrease of mPAP (median 18.4%; interquartile range [IQR] 8.9%-27.0%) with a reduction in PVR (median 50.5%; IQR, 45.4%-70.7%), and an increase in both cardiac output (CO) (median 28.1%; IQR 5.7%-63.8%) and PAWP (median 50.0%; IQR 16.7%-108.3%) before LT. One year posttransplant survival was 69% (11/16); however, only 1 death was attributed to POPH. At 1-year posttransplant, 63.6% (7/11) of patients were weaned off all PAH therapy with clinical and echocardiographic resolution of POPH. CONCLUSIONS: In treated POPH patients with an mPAP ≥35 mm Hg and PVR < 250 dynes-s-cm-5 before LT, 1-year posttransplant survival was 69% and the majority of patients were able to discontinue PAH therapy.

Anesthetic considerations for combined heart--liver transplantation in patients with Fontan-associated liver disease.

PURPOSE OF REVIEW: The success of the Fontan procedure has led to increased survival of patients born with certain congenital heart disease to the point that new sequlae, as a result of Fontan circulation, are being discovered. Included among these is Fontan-associated liver disease (FALD). The purpose of this review is to present available literature on the perioperative management of the combined heart--liver transplantation (CHLT) in patients with FALD. RECENT FINDINGS: The perioperative management of a combined heart-liver transplant in a patient with Fontan circulation is complex. The patient is at risk for hemodynamic disturbances, significant blood loss, coagulopathies, and metabolic derangements. The maintenance of an appropriate transpulmonary pressure gradient is paramount to success. Postoperative management should be accomplished by a multidisciplinary care team. Limited series have demonstrated good outcomes in patients who have undergone CHLT. SUMMARY: The perioperative management of CHLT in patients with FALD is complex and available literature is limited. Future studies are needed to further assess proper perioperative management of patients with FALD who undergo CHLT.

Survival of Lassa Virus in Blood and Tissue Culture Media and in a Small Particle Aerosol.

Knowledge of the survival and stability of a pathogen is important for understanding its risk, reducing its transmission, and establishing control measures. Lassa virus is endemic in West Africa, causes severe disease, and is an emerging pathogen of concern. Our study examined the survival of Lassa virus in blood and tissue culture media at two different temperatures. The stability of Lassa virus held within a small particle aerosol was also measured. In liquids, Lassa virus was found to decay more quickly at 30 °C compared to room temperature. Sealed samples protected from environmental desiccation were more stable than samples open to the environment. In a small particle aerosol, the decay rate of Lassa virus was determined at 2.69% per minute. This information can contribute to risk assessments and inform mitigation strategies in the event of an outbreak of Lassa virus.

Experimental aerosol survival of SARS-CoV-2 in artificial saliva and tissue culture media at medium and high humidity.

SARS-CoV-2, the causative agent of the COVID-19 pandemic, may be transmitted via airborne droplets or contact with surfaces onto which droplets have deposited. In this study, the ability of SARS-CoV-2 to survive in the dark, at two different relative humidity values and within artificial saliva, a clinically relevant matrix, was investigated. SARS-CoV-2 was found to be stable, in the dark, in a dynamic small particle aerosol under the four experimental conditions we tested and viable virus could still be detected after 90 minutes. The decay rate and half-life was determined and decay rates ranged from 0.4 to 2.27 % per minute and the half lives ranged from 30 to 177 minutes for the different conditions. This information can be used for advice and modelling and potential mitigation strategies.