Carrying eggs uphill: are costs of reproduction stronger on steeper slopes?

Locomotor impairment during pregnancy is a well-documented cost of reproduction, but most empirical studies have not incorporated ecological complexity, such as locomotion on sloping inclines rather than horizontal surfaces. Biomechanical factors suggest that carrying a heavy burden-including shifts in the body's centre of mass-may impair locomotor ability even more when an animal is running uphill. If so, then measuring costs of reproduction on horizontal racetracks may underestimate these costs in nature for arboreal species. To evaluate this prediction, we measured the pregnancy-induced reduction in speed for jacky dragons (Amphibolurus muricatus) at inclines ranging from 0 to 45°. Both pregnancy and steeper slopes reduced lizard performance, but pregnancy did not exacerbate the locomotor decrement on steeper racetracks. An ability to maintain mobility on steep slopes during pregnancy may be a target of selection in arboreal taxa. To understand the evolutionary context of locomotion-based costs of reproduction, we also need studies on the relationship between organismal performance and ecologically relevant measures such as predation risk.

Prevention of Respiratory Syncytial Virus Infection in Healthy Adults by a Single Immunization of Ad26.RSV.preF in a Human Challenge Study.

BACKGROUND: Respiratory syncytial virus (RSV) is a significant cause of severe lower respiratory tract disease in children and older adults, but has no approved vaccine. This study assessed the potential of Ad26.RSV.preF to protect against RSV infection and disease in an RSV human challenge model. METHODS: In this double-blind, placebo-controlled study, healthy adults aged 18-50 years were randomized 1:1 to receive 1 × 1011 vp Ad26.RSV.preF or placebo intramuscularly. Twenty-eight days postimmunization, volunteers were challenged intranasally with RSV-A (Memphis 37b). Assessments included viral load (VL), RSV infections, clinical symptom score (CSS), safety, and immunogenicity. RESULTS: Postchallenge, VL, RSV infections, and disease severity were lower in Ad26.RSV.preF (n = 27) vs placebo (n = 26) recipients: median VL area under the curve (AUC) quantitative real-time polymerase chain reaction: 0.0 vs 236.0 (P = .012; predefined primary endpoint); median VL-AUC quantitative culture: 0.0 vs 109; RSV infections 11 (40.7%) vs 17 (65.4%); median RSV AUC-CSS 35 vs 167, respectively. From baseline to 28 days postimmunization, geometric mean fold increases in RSV A2 neutralizing antibody titers of 5.8 and 0.9 were observed in Ad26.RSV.preF and placebo, respectively. Ad26.RSV.preF was well tolerated. CONCLUSIONS: Ad26.RSV.preF demonstrated protection from RSV infection through immunization in a human challenge model, and therefore could potentially protect against natural RSV infection and disease. CLINICAL TRIALS REGISTRATION: NCT03334695; CR108398, 2017-003194-33 (EudraCT); VAC18193RSV2002.

Minimal transmission in an influenza A (H3N2) human challenge-transmission model within a controlled exposure environment.

Uncertainty about the importance of influenza transmission by airborne droplet nuclei generates controversy for infection control. Human challenge-transmission studies have been supported as the most promising approach to fill this knowledge gap. Healthy, seronegative volunteer 'Donors' (n = 52) were randomly selected for intranasal challenge with influenza A/Wisconsin/67/2005 (H3N2). 'Recipients' randomized to Intervention (IR, n = 40) or Control (CR, n = 35) groups were exposed to Donors for four days. IRs wore face shields and hand sanitized frequently to limit large droplet and contact transmission. One transmitted infection was confirmed by serology in a CR, yielding a secondary attack rate of 2.9% among CR, 0% in IR (p = 0.47 for group difference), and 1.3% overall, significantly less than 16% (p<0.001) expected based on a proof-of-concept study secondary attack rate and considering that there were twice as many Donors and days of exposure. The main difference between these studies was mechanical building ventilation in the follow-on study, suggesting a possible role for aerosols.

Environmental conditions and male quality traits simultaneously explain variation of multiple colour signals in male lizards.

Male lizards often display multiple pigment-based and structural colour signals which may reflect various quality traits (e.g. performance, parasitism), with testosterone (T) often mediating these relationships. Furthermore, environmental conditions can explain colour signal variation by affecting processes such as signal efficacy, thermoregulation and camouflage. The relationships between colour signals, male quality traits and environmental factors have often been analysed in isolation, but simultaneous analyses are rare. Thus, the response of multiple colour signals to variation in all these factors in an integrative analysis remains to be investigated. Here, we investigated how multiple colour signals relate to their information content, examined the role of T as a potential mediator of these relationships and how environmental factors explain colour signal variation. We performed an integrative study to examine the covariation between three colour signals (melanin-based black, carotenoid-based yellow-orange and structural UV), physiological performance, parasitism, T levels and environmental factors (microclimate, forest cover) in male common lizards Zootoca vivipara from 13 populations. We found that the three colour signals conveyed information on different aspects of male condition, supporting a multiple message hypothesis. T influenced only parasitism, suggesting that T does not directly mediate the relationships between colour signals and their information content. Moreover, colour signals became more saturated in forested habitats, suggesting an adaptation to degraded light conditions, and became generally brighter in mesic conditions, in contradiction with the thermal melanism hypothesis. We show that distinct individual quality traits and environmental factors simultaneously explain variations of multiple colour signals with different production modes. Our study therefore highlights the complexity of colour signal evolution, involving various sets of selective pressures acting at the same time, but in different ways depending on colour production mechanism.

Les lézards mâles arborent souvent plusieurs signaux colorés de nature pigmentaire et structurale qui reflètent de multiples traits de qualité (e.g. performance, parasitisme), et la testostérone (T) joue souvent un rôle de médiateur dans ces relations. En outre, les conditions environnementales peuvent également expliquer les variations des signaux colorés en influençant des aspects tels que l'efficacité des signaux, la thermorégulation ou le camouflage. Les relations entre signaux colorés, traits de qualité individuelle et facteurs environnementaux ont souvent été analysées séparément, mais rarement de manière simultanée. Ainsi, la réponse de ces multiples signaux colorés aux variations de tous ces facteurs reste à explorer dans le contexte d'une étude intégrative. Ici, nous explorons la relation entre ces multiples signaux colorés et leur contenu informatif, nous examinons le rôle de T comme médiateur potentiel de ces relations et nous recherchons si les conditions environnementales expliquent la variation de ces signaux colorés. Nous avons mené une étude intégrative afin d'examiner la covariation entre trois types de signaux colorés (noir produit par la mélanine, jaune-orange produit par les caroténoïdes et UV produit par des éléments structuraux), la performance physiologique, le parasitisme, les niveaux de T et les conditions environnementales (e.g. microclimat, couverture forestière) chez des mâles du lézard vivipare (Zootoca vivipara) provenant de 13 populations. Nos résultats indiquent que les trois signaux colorés transmettent des informations sur différents aspects de la condition des mâles, en accord avec l'hypothèse de « messages multiples ¼. T influence uniquement le parasitisme, suggérant que T n'agit pas en tant que médiateur des relations entre ces signaux colorés et leur contenu informatif. De plus, les signaux colorés sont plus saturés dans les habitats les plus forestiers, ce qui suggère une adaptation à des conditions lumineuses dégradées. Enfin, les signaux colorés sont plus intenses lorsque les conditions sont mésiques, en contradiction avec l'hypothèse du mélanisme thermal. Nous démontrons que différents traits de qualité individuelle et facteurs environnementaux expliquent de manière simultanée les variations de multiples signaux colorés impliquant différents modes de production. Notre étude souligne ainsi la complexité de l'évolution des signaux colorés, qui implique plusieurs types de pressions de sélection agissant en même temps mais dans des directions différentes selon le mode de production.

Patient, clinician and manager experience of the accelerated implementation of virtual consultations following COVID-19: A qualitative study of preferences in a tertiary orthopaedic rehabilitation setting.

AIM: To investigate the experiences of patients, clinicians and managers during the accelerated implementation of virtual consultations (VCs) due to COVID-19. To understand how patient preferences are constructed and organized. METHODS: Semi-structured interviews with patients, clinicians and managerial staff at a single specialist orthopaedic centre in the United Kingdom. The interview schedule and coding frame were based on Normalisation Process Theory. Interviews were conducted over the telephone or by video call. Abductive analysis of interview transcripts extended knowledge from previous research to identify, characterize and explain how patient preferences for VC were formed and arranged. RESULTS: Fifty-five participants were included (20 patients, 20 clinicians, 15 managers). Key mechanisms that contribute to the formation of patient preferences were identified. These were: (a) context for the consultation (normative expectations, relational expectations, congruence and potential); (b) the available alternatives and the implementation process (coherence, cognitive participation, collective action and reflexive monitoring). Patient preferences are mediated by the clinician and organisational preferences through the influence of the consultation context, available alternatives and the implementation process. CONCLUSIONS: This study reports the cumulative analysis of five empirical studies investigating patient preferences for VC before and during the COVID-19 pandemic as VC transitioned from an experimental clinic to a compulsory form of service delivery. This study has identified mechanisms that explain how preferences for VC come about and how these relate to organisational and clinician preferences. Since clinical pathways are shaped by interactions between patient, clinicians and organisational preferences, future service design must strike a balance between patient preferences and the preferences of clinicians and organisations. PATIENT AND PUBLIC CONTRIBUTION: The CONNECT Project Patient and Public Involvement (PPI) group provided guidance on the conduct and design of the research. This took place with remote meetings between the lead researcher and the chair of the PPI group during March and April 2020. Patient information documentation and the interview schedule were developed with the PPI group to ensure that these were accessible.

A mixed-methods survey to explore issues with virtual consultations for musculoskeletal care during the COVID-19 pandemic.

OBJECTIVE: To explore orthopaedic and musculoskeletal clinicians' views and experiences of legal, safety, safeguarding and security issues regarding the use of virtual consultations (VC) during the COVID-19 pandemic. A secondary objective was to suggest ways to overcome these issues. METHODS: A mixed method cross-sectional survey was conducted, seeking the views and experiences of orthopaedic and musculoskeletal medically qualified and Allied Health Professionals in the United Kingdom. Descriptive statistical analysis was employed for quantitative data and a qualitative content analysis undertaken for qualitative data. Findings were presented in accordance with the four key issues. RESULTS: Two hundred and ninety professionals (206 physiotherapists, 78 medically qualified professionals, 6 'other' therapists) participated in the survey. Of the 290 participants, 260 (90%) were not using VC prior to the COVID-19 pandemic, 248 respondents (86%) were unsure whether their professional indemnity insurance covered VC, 136 (47%) had considered how they would handle an issue of safeguarding whilst the remainder had not, 126 (43%) had considered what they would do if, during a virtual consultation, a patient suffered an injury (e.g. bang on their head) or a fall (e.g. mechanical or a medical event like syncope) and 158 (54%) reported they felt the current technological solutions are secure in terms of patient data. Qualitative data provided additional context to support the quantitative findings such as validity of indemnification, accuracy of diagnosis and consent using VC, safeguarding issues; and security and sharing of data. Potential changes to practice have been proposed to address these issues. CONCLUSIONS: VC have been rapidly deployed since the onset of the COVID-19 pandemic often without clear guidance or consensus on many important issues. This study identified legal, safeguarding, safety and security issues. There is an urgent need to address these and develop local and national guidance and frameworks to facilitate ongoing safe virtual orthopaedic practice beyond the COVID-19 pandemic.

Enhanced rehabilitation and care models for adults with dementia following hip fracture surgery.

BACKGROUND: Hip fracture is a major injury that causes significant problems for affected individuals and their family and carers. Over 40% of people with hip fracture have dementia or cognitive impairment. The outcomes of these individuals after surgery are poorer than for those without dementia. It is unclear which care and rehabilitation interventions achieve the best outcomes for these people. This is an update of a Cochrane Review first published in 2013. OBJECTIVES: (a) To assess the effectiveness of models of care including enhanced rehabilitation strategies designed specifically for people with dementia following hip fracture surgery compared to usual care. (b) To assess for people with dementia the effectiveness of models of care including enhanced rehabilitation strategies that are designed for all older people, regardless of cognitive status, following hip fracture surgery, compared to usual care. SEARCH METHODS: We searched ALOIS (www.medicine.ox.ac.uk/alois), the Cochrane Dementia and Cognitive Improvement Group Specialised Register, MEDLINE (OvidSP), Embase (OvidSP), PsycINFO (OvidSP), CINAHL (EBSCOhost), Web of Science Core Collection (ISI Web of Science), LILACS (BIREME), ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform on 16 October 2019. SELECTION CRITERIA: We included randomised and quasi-randomised controlled trials evaluating the effectiveness of any model of enhanced care and rehabilitation for people with dementia after hip fracture surgery compared to usual care. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials for inclusion and extracted data. We assessed risk of bias of the included trials. We synthesised data only if we considered the trials to be sufficiently homogeneous in terms of participants, interventions, and outcomes. We used the GRADE approach to rate the overall certainty of evidence for each outcome. MAIN RESULTS: We included seven trials with a total of 555 participants. Three trials compared models of enhanced care in the inpatient setting with conventional care. Two trials compared an enhanced care model provided in inpatient settings and at home after discharge with conventional care. Two trials compared geriatrician-led care in-hospital to conventional care led by the orthopaedic team. None of the interventions were designed specifically for people with dementia, therefore the data included in the review were from subgroups of people with dementia or cognitive impairment participating in randomised controlled trials investigating models of care for all older people following hip fracture. The end of follow-up in the trials ranged from the point of acute hospital discharge to 24 months after discharge. We considered all trials to be at high risk of bias in more than one domain. As subgroups of larger trials, the analyses lacked power to detect differences between the intervention groups. Furthermore, there were some important differences in baseline characteristics of participants between the experimental and control groups. Using the GRADE approach, we downgraded the certainty of the evidence for all outcomes to low or very low. The effect estimates for almost all comparisons were very imprecise, and the overall certainty for most results was very low. There were no data from any study for our primary outcome of health-related quality of life. There was only very low certainty for our other primary outcome, activities of daily living and functional performance, therefore we were unable to draw any conclusions with confidence. There was low-certainty that enhanced care and rehabilitation in-hospital may reduce rates of postoperative delirium (odds ratio 0.04, 95% confidence interval (CI) 0.01 to 0.22, 2 trials, n = 141) and very low-certainty associating it with lower rates of some other complications. There was also low-certainty that, compared to orthopaedic-led management, geriatrician-led management may lead to shorter hospital stays (mean difference 4.00 days, 95% CI 3.61 to 4.39, 1 trial, n = 162). AUTHORS' CONCLUSIONS: We found limited evidence that some of the models of enhanced rehabilitation and care used in the included trials may show benefits over usual care for preventing delirium and reducing length of stay for people with dementia who have been treated for hip fracture. However, the certainty of these results is low. Data were available from only a small number of trials, and the certainty for all other results is very low. Determining the optimal strategies to improve outcomes for this growing population of patients should be a research priority.

The Effect of Influenza Virus on the Human Oropharyngeal Microbiome.

BACKGROUND: Secondary bacterial infections are an important cause of morbidity and mortality associated with influenza infections. As bacterial disease can be caused by a disturbance of the host microbiome, we examined the impact of influenza on the upper respiratory tract microbiome in a human challenge study. METHODS: The dynamics and ecology of the throat microbiome were examined following an experimental influenza challenge of 52 previously-healthy adult volunteers with influenza A/Wisconsin/67/2005 (H3N2) by intranasal inoculation; 35 healthy control subjects were not subjected to the viral challenge. Serial oropharyngeal samples were taken over a 30-day period, and the V1-V3 region of the bacterial 16S ribosomal RNA sequences were amplified and sequenced to determine the composition of the microbiome. The carriage of pathogens was also detected. RESULTS: Of the 52 challenged individuals, 43 developed proven influenza infections, 33 of whom became symptomatic. None of the controls developed influenza, although 22% reported symptoms. The diversity of bacterial communities remained remarkably stable following the acquisition of influenza, with no significant differences over time between individuals with influenza and those in the control group. Influenza infection was not associated with perturbation of the microbiome at the level of phylum or genus. There was no change in colonization rates with Streptococcus pneumoniae or Neisseria meningitidis. CONCLUSIONS: The throat microbiota is resilient to influenza infection, indicating the robustness of the upper-airway microbiome.

Antagonistic Responses of Exposure to Sublethal Temperatures: Adaptive Phenotypic Plasticity Coincides with a Reduction in Organismal Performance.

A fitness benefit of phenotypic plasticity is the ability of an organism to survive short-term, deleterious environmental fluctuations. Yet the influence of selection on plasticity in modulating shifts in phenotypic traits remains unclear. Short-term phenotypic plasticity in thermal tolerance traits is attained by exposure to sublethal hot or cold temperatures (i.e., the hardening response). Heat hardening is expected to buffer organisms from the unpredictability of extreme thermal fluctuations in the environment so as to minimize interruptions in activity and enhance survival. However, exposure to sublethal temperatures might entail other phenotypic costs that constrain or inhibit the prolonged use of hardening responses across longer timescales. Here we estimated the onset of the heat hardening response, physiological and behavioral shifts during heat hardening, and geographic variation in heat hardening using tree lizards (Urosaurus ornatus). Peak heat hardening occurred 6 h after exposure to sublethal temperatures. We found that both preferred body temperatures and locomotor performance diminished following exposure to sublethal temperatures, and performance levels did not approach preexposure levels until after the peak hardening response. We also found support for intraspecific variation in the hardening response along an environmental gradient, where populations in more thermally variable environments exhibited stronger plastic responses and populations with higher baseline heat tolerances exhibited weaker plastic responses. Sublethal temperature exposure might induce adaptive plasticity in thermal tolerance; however, we find that these responses entail other phenotypic shifts that might curtail chronic reliance on plasticity in thermal traits as a mechanism of responding to changes in thermal environments induced by climate warming.

The effective rate of influenza reassortment is limited during human infection.

We characterise the evolutionary dynamics of influenza infection described by viral sequence data collected from two challenge studies conducted in human hosts. Viral sequence data were collected at regular intervals from infected hosts. Changes in the sequence data observed across time show that the within-host evolution of the virus was driven by the reversion of variants acquired during previous passaging of the virus. Treatment of some patients with oseltamivir on the first day of infection did not lead to the emergence of drug resistance variants in patients. Using an evolutionary model, we inferred the effective rate of reassortment between viral segments, measuring the extent to which randomly chosen viruses within the host exchange genetic material. We find strong evidence that the rate of effective reassortment is low, such that genetic associations between polymorphic loci in different segments are preserved during the course of an infection in a manner not compatible with epistasis. Combining our evidence with that of previous studies we suggest that spatial heterogeneity in the viral population may reduce the extent to which reassortment is observed. Our results do not contradict previous findings of high rates of viral reassortment in vitro and in small animal studies, but indicate that in human hosts the effective rate of reassortment may be substantially more limited.

Thermal physiology and thermoregulatory behaviour exhibit low heritability despite genetic divergence between lizard populations.

Ectothermic species are particularly sensitive to changes in temperature and may adapt to changes in thermal environments through evolutionary shifts in thermal physiology or thermoregulatory behaviour. Nevertheless, the heritability of thermal traits, which sets a limit on evolutionary potential, remains largely unexplored. In this study, we captured brown anole lizards (Anolis sagrei) from two populations that occur in contrasting thermal environments. We raised offspring from these populations in a laboratory common garden and compared the shape of their thermal performance curves to test for genetic divergence in thermal physiology. Thermal performance curves differed between populations in a common garden in ways partially consistent with divergent patterns of natural selection experienced by the source populations, implying that they had evolved in response to selection. Next, we estimated the heritability of thermal performance curves and of several traits related to thermoregulatory behaviour. We did not detect significant heritability in most components of the thermal performance curve or in several aspects of thermoregulatory behaviour, suggesting that contemporary selection is unlikely to result in rapid evolution. Our results indicate that the response to selection may be slow in the brown anole and that evolutionary change is unlikely to keep pace with current rates of environmental change.

The human viral challenge model: accelerating the evaluation of respiratory antivirals, vaccines and novel diagnostics.

The Human Viral Challenge (HVC) model has, for many decades, helped in the understanding of respiratory viruses and their role in disease pathogenesis. In a controlled setting using small numbers of volunteers removed from community exposure to other infections, this experimental model enables proof of concept work to be undertaken on novel therapeutics, including vaccines, immunomodulators and antivirals, as well as new diagnostics.Crucially, unlike conventional phase 1 studies, challenge studies include evaluable efficacy endpoints that then guide decisions on how to optimise subsequent field studies, as recommended by the FDA and thus licensing studies that follow. Such a strategy optimises the benefit of the studies and identifies possible threats early on, minimising the risk to subsequent volunteers but also maximising the benefit of scarce resources available to the research group investing in the research. Inspired by the principles of the 3Rs (Replacement, Reduction and Refinement) now commonly applied in the preclinical phase, HVC studies allow refinement and reduction of the subsequent development phase, accelerating progress towards further statistically powered phase 2b studies. The breadth of data generated from challenge studies allows for exploration of a wide range of variables and endpoints that can then be taken through to pivotal phase 3 studies.We describe the disease burden for acute respiratory viral infections for which current conventional development strategies have failed to produce therapeutics that meet clinical need. The Authors describe the HVC model's utility in increasing scientific understanding and in progressing promising therapeutics through development.The contribution of the model to the elucidation of the virus-host interaction, both regarding viral pathogenicity and the body's immunological response is discussed, along with its utility to assist in the development of novel diagnostics.Future applications of the model are also explored.

The use of assistive technology in shoulder exercise rehabilitation - a qualitative study of acceptability within a pilot project.

BACKGROUND: Painful shoulders pose a substantial socioeconomic burden accounting for 2.4% of all primary care consultations in the UK. There is a strong evidence to indicate that the majority of this shoulder pain can be managed successfully with exercise based treatments and that common surgical procedures provide no extra benefit. Patient adherence and engagement is cited as an important factor in gaining positive outcomes. The MUJO System has been designed to help target the rehabilitation of the rotator cuff muscles which are commonly recommended for the management of shoulder pain. The purpose of this qualitative study was to evaluate the acceptability of the MUJO System amongst clinicians and patients. METHODS: A qualitative study was undertaken to look at the usability of the MUJO System both from clinicians' and patients' perspectives. Patients with shoulder problems were identified by an experienced physiotherapist using the study eligibility criteria. and invited to participate. Semi-structured interviews were performed with patients and clinicians to explore factors surrounding its acceptability and feasibility of use. The study was designed using Normalisation Process Theory as a theoretical basis for the inquiry. RESULTS: Seven physiotherapists and ten patients were interviewed in the study. The Internal and External Devices were seen as having the potential to rehabilitate the rotator cuff however it posed limitations towards more functional based exercises. Patients and clinicians found the visual feedback from the Patient App enhanced the rehabilitation experience. The Internal and External Devices were acceptable to all for rehabilitation providing the devices were available for use by the patients in the community. CONCLUSION: Patients and clinicians found the MUJO System acceptable as a modality to perform shoulder exercises. For the MUJO System to be taken up as a routine part of clinical practice patients need to be able to access the devices in the community. For the MUJO System to be taken up in clinical practice it needs to be workable within the context of the treatment pathway and not interfere with standard processes.

Natural selection on thermal preference, critical thermal maxima and locomotor performance.

Climate change is resulting in a radical transformation of the thermal quality of habitats across the globe. Whereas species have altered their distributions to cope with changing environments, the evidence for adaptation in response to rising temperatures is limited. However, to determine the potential of adaptation in response to thermal variation, we need estimates of the magnitude and direction of natural selection on traits that are assumed to increase persistence in warmer environments. Most inferences regarding physiological adaptation are based on interspecific analyses, and those of selection on thermal traits are scarce. Here, we estimate natural selection on major thermal traits used to assess the vulnerability of ectothermic organisms to altered thermal niches. We detected significant directional selection favouring lizards with higher thermal preferences and faster sprint performance at their optimal temperature. Our analyses also revealed correlational selection between thermal preference and critical thermal maxima, where individuals that preferred warmer body temperatures with cooler critical thermal maxima were favoured by selection. Recent published estimates of heritability for thermal traits suggest that, in concert with the strong selective pressures we demonstrate here, evolutionary adaptation may promote long-term persistence of ectotherms in altered thermal environments.

Deep Sequencing of Influenza A Virus from a Human Challenge Study Reveals a Selective Bottleneck and Only Limited Intrahost Genetic Diversification.

Knowledge of influenza virus evolution at the point of transmission and at the intrahost level remains limited, particularly for human hosts. Here, we analyze a unique viral data set of next-generation sequencing (NGS) samples generated from a human influenza challenge study wherein 17 healthy subjects were inoculated with cell- and egg-passaged virus. Nasal wash samples collected from 7 of these subjects were successfully deep sequenced. From these, we characterized changes in the subjects' viral populations during infection and identified differences between the virus in these samples and the viral stock used to inoculate the subjects. We first calculated pairwise genetic distances between the subjects' nasal wash samples, the viral stock, and the influenza virus A/Wisconsin/67/2005 (H3N2) reference strain used to generate the stock virus. These distances revealed that considerable viral evolution occurred at various points in the human challenge study. Further quantitative analyses indicated that (i) the viral stock contained genetic variants that originated and likely were selected for during the passaging process, (ii) direct intranasal inoculation with the viral stock resulted in a selective bottleneck that reduced nonsynonymous genetic diversity in the viral hemagglutinin and nucleoprotein, and (iii) intrahost viral evolution continued over the course of infection. These intrahost evolutionary dynamics were dominated by purifying selection. Our findings indicate that rapid viral evolution can occur during acute influenza infection in otherwise healthy human hosts when the founding population size of the virus is large, as is the case with direct intranasal inoculation. IMPORTANCE: Influenza viruses circulating among humans are known to rapidly evolve over time. However, little is known about how influenza virus evolves across single transmission events and over the course of a single infection. To address these issues, we analyze influenza virus sequences from a human challenge experiment that initiated infection with a cell- and egg-passaged viral stock, which appeared to have adapted during its preparation. We find that the subjects' viral populations differ genetically from the viral stock, with subjects' viral populations having lower representation of the amino-acid-changing variants that arose during viral preparation. We also find that most of the viral evolution occurring over single infections is characterized by further decreases in the frequencies of these amino-acid-changing variants and that only limited intrahost genetic diversification through new mutations is apparent. Our findings indicate that influenza virus populations can undergo rapid genetic changes during acute human infections.

Virus-specific antibody secreting cell, memory B-cell, and sero-antibody responses in the human influenza challenge model.

BACKGROUND: Antibodies play a major role in the protection against influenza virus in human. However, the antibody level is usually short-lived and the cellular mechanisms underlying influenza virus-specific antibody response to acute infection remain unclear. METHODS: We studied the kinetics and magnitude of influenza virus-specific B-cell and serum antibody responses in relation to virus replication during the course of influenza infection in healthy adult volunteers who were previously seronegative and experimentally infected with seasonal influenza H1N1 A/Brisbane/59/07 virus. RESULTS: Our data demonstrated a robust expansion of the virus-specific antibody-secreting cells (ASCs) and memory B cells in the peripheral blood, which correlated with both the throat viral load and the duration of viral shedding. The ASC response was obviously detected on day 7 post-infection when the virus was completely cleared from nasal samples, and serum hemagglutination-inhibition antibodies were still undetectable. On day 28 postinfection, influenza virus-specific B cells were further identified from the circulating compartment of isotype-switched B cells. CONCLUSIONS: Virus-specific ASCs could be the earliest marker of B-cell response to a new flu virus infection, such as H7N9 in humans.

Video analysis of communication by physiotherapists and patients in video consultations: a qualitative study using conversation analysis.

OBJECTIVES: To investigate the challenges of doing physical examinations and exercises by video, and the communication strategies used by physiotherapists and patients to overcome them. DESIGN: A qualitative study of talk and social actions, examining the verbal and non-verbal communication practices used by patients and physiotherapists. Video consultations between physiotherapists and patients were video recorded using MS Teams, transcribed and analysed in detail using Conversation Analysis. SETTING: Video consultations were recorded in three specialist settings (long-term pain, orthopaedics, and neuromuscular rehabilitation) across two NHS hospitals. PARTICIPANTS: 15 adult patients (10 female, 5 male; aged 20-77) with a scheduled video consultation. RESULTS: Examinations and exercises retain-->were successfully accomplished in all 15 consultations. Two key challenges were identified for physiotherapists and patients when doing video assessments: (1) managing safety and clinical risk, and (2) making exercises and movements visible. Challenges were addressed by through communication practices that were patient-centred and tailored to the video context (e.g., explaining how to frame the body to the camera or adjust the camera to make the body visible). CONCLUSIONS: Video is being used by physiotherapists to consult with their patients. This can work well, but tailored communication strategies are critical to help participants overcome the challenges of remote physical examinations and exercises. CONTRIBUTION OF THE PAPER: This paper is a first to use video-based analysis to determine the challenges of video consulting for doing remote assessments and exercises in physiotherapy settings. It demonstrates how patients and physiotherapists use communication strategies to raise concerns around safety and visibility and how they overcome these concerns.

Adoption of technology enabled care to support the management of children and teenagers in rheumatology services: a protocol for a mixed-methods systematic review.

INTRODUCTION: COVID-19 catalysed a rapid move to provide care away from the hospital using online communication platforms. Technology enabled care (TEC) continues to be an important driver in progressing future healthcare services. Due to the complex and chronic nature of conditions seen within paediatric rheumatology, TEC may lead to better outcomes. Despite some growth in published literature into the adoption of TEC in paediatric rheumatology, there is limited synthesis. The aim of this review is to provide a comprehensive understanding and evaluation of the adoption of TEC by patients in paediatric rheumatology services, to establish best practices. METHODS AND ANALYSIS: This proposed mixed-methods systematic review will be conducted by searching a wide variety of healthcare databases, grey literature resources and associated charities and societies, for articles reported in English language. Data extraction will include population demographics, technology intervention, factors affecting adoption of intervention and consequent study outcomes. A parallel-results convergent synthesis design is planned, with independent syntheses of quantitative and qualitative data, followed by comparison of the findings of each synthesis using a narrative approach. Normalisation process theory will be used to identify, characterise and explain implementation factors. The quality of included articles will be assessed using the Mixed Methods Appraisal Tool for research papers and the Authority, Accuracy, Coverage, Objectivity, Date, Significance checklist for grey literature. Overall confidence in quality and strength of evidence will be assessed using the Confidence in the Evidence from Reviews of Qualitative Research tool. ETHICS AND DISSEMINATION: Ethical approval is not required due to the nature of this mixed-methods systematic review. The findings will be disseminated via a peer-reviewed journal, relevant conferences and any other methods (eg, via NHS Trust or NIHR YouTube channels) as advised by paediatric rheumatology patients. PROSPERO REGISTRATION NUMBER: CRD42023443058.

Use of a human influenza challenge model to assess person-to-person transmission: proof-of-concept study.

BACKGROUND: Influenza transmission in humans remains poorly understood. In particular, the relative contribution of contact, large droplet, and aerosol transmission is unknown. The aims of this proof-of-concept study were to determine whether an experimentally induced influenza infection is transmissible between humans and whether this would form a viable platform for future studies. METHODS: In a quarantine facility, healthy volunteers ("donors") were inoculated with A/Wisconsin/67/2005 (H3N2) influenza virus via intranasal drops. On study days 2 and 3 "recipient" volunteers were exposed to donors under close living conditions. Volunteers socialized for 30 hours during a 2-day period. Infection was confirmed by ≥1 positive results from polymerase chain reaction, virus culture, or serology. RESULTS: After inoculation, 4 of 9 donors developed symptoms consistent an influenza-like illness (ILI) and 7 of 9 were proven to be influenza-infected. After exposure, 4 of 15 recipients developed symptoms of ILI and 3 of 15 were proven to be infected. Serum collected within 2 days of study initiation indicated that 1 donor and 3 recipients were seropositive at study initiation. After adjustment for preexposure immunity, the overall secondary attack rate was 25% (3 of 12). CONCLUSIONS: Experimental human exposure studies offer an attractive potential method for answering outstanding questions related to influenza transmission and the evaluation of interventions to reduce it.