Seroconversion and fever are dose-dependent in a nonhuman primate model of inhalational COVID-19.

While evidence exists supporting the potential for aerosol transmission of SARS-CoV-2, the infectious dose by inhalation remains unknown. In the present study, the probability of infection following inhalation of SARS-CoV-2 was dose-dependent in a nonhuman primate model of inhalational COVID-19. The median infectious dose, assessed by seroconversion, was 52 TCID50 (95% CI: 23-363 TCID50), and was significantly lower than the median dose for fever (256 TCID50, 95% CI: 102-603 TCID50), resulting in a group of animals that developed an immune response post-exposure but did not develop fever or other clinical signs of infection. In a subset of these animals, virus was detected in nasopharyngeal and/or oropharyngeal swabs, suggesting that infected animals without signs of disease are able to shed virus and may be infectious, which is consistent with reports of asymptomatic spread in human cases of COVID-19. These results suggest that differences in exposure dose may be a factor influencing disease presentation in humans, and reinforce the importance of public health measures that limit exposure dose, such as social distancing, masking, and increased ventilation. The dose-response data provided by this study are important to inform disease transmission and hazard modeling, and, ultimately, mitigation strategies. Additionally, these data will be useful to inform dose selection in future studies examining the efficacy of therapeutics and vaccines against inhalational COVID-19, and as a baseline in healthy, young adult animals for assessment of the importance of other factors, such as age, comorbidities, and viral variant, on the infectious dose and disease presentation.

Student-led exercise testing and prescription has benefits for both students and their community volunteers.

Service learning opportunities allow students to apply their knowledge and skills through engagement with their community. Previous studies have suggested that student-led exercise testing and health screening can benefit both students and their community participants. In a third-year kinesiology course, "Physiological Assessment and Training," students at the University of Prince Edward Island are provided with an introduction to health-focused personal training and develop and manage personalized training programs for community volunteers. The purpose of this study was to investigate the impact of student-led training programs on student learning. A secondary purpose was to investigate the perceptions of community members participating in the program. Community participants included 13 men and 43 women with stable health (mean age: 52.3 ± 10.0 yr). Students led participants through aerobic and musculoskeletal fitness tests before and after completion of a 4-wk student-designed training program based on participants' fitness and interests. Students reported that the program was enjoyable and improved understanding of fitness concepts and confidence in personal training. Community participants rated the programs as enjoyable and appropriate and viewed students as professional and knowledgeable. These results suggest that student-led personal training programs provide meaningful benefits to students and their community volunteers.NEW & NOTEWORTHY Undergraduate kinesiology students oversaw exercise testing and 4 wk of supervised exercise for community volunteers. Both students and their community participants reported enjoying the experience, and students stated that it also improved their understanding and confidence. These results suggest that student-led personal training programs provide meaningful benefits to students and their community volunteers.

The Stability of an Isolate of the SARS-CoV-2 B.1.1.7 Lineage in Aerosols Is Similar to 3 Earlier Isolates.

BACKGROUND: Our laboratory previously examined the influence of environmental conditions on the stability of an early isolate of SARS-CoV-2 (hCoV-19/USA/WA-1/2020) in aerosols generated from culture medium or simulated saliva. However, genetic differences have emerged among SARS-CoV-2 lineages, and it is possible that these differences may affect environmental stability and the potential for aerosol transmission. METHODS: The influence of temperature, relative humidity, and simulated sunlight on the decay of 4 SARS-CoV-2 isolates in aerosols, including 1 belonging to the recently emerged B.1.1.7 lineage, were compared in a rotating drum chamber. Aerosols were generated from simulated respiratory tract lining fluid to represent aerosols originating from the deep lung. RESULTS: No differences in the stability of the isolates were observed in the absence of simulated sunlight at either 20°C or 40°C. However, a small but statistically significant difference in the stability was observed between some isolates in simulated sunlight at 20°C and 20% relative humidity. CONCLUSIONS: The stability of SARS-CoV-2 in aerosols does not vary greatly among currently circulating lineages, including B.1.1.7, suggesting that the increased transmissibility associated with recent SARS-CoV-2 lineages is not due to enhanced survival in the environment.

Simulated Sunlight Rapidly Inactivates SARS-CoV-2 on Surfaces.

Previous studies have demonstrated that SARS-CoV-2 is stable on surfaces for extended periods under indoor conditions. In the present study, simulated sunlight rapidly inactivated SARS-CoV-2 suspended in either simulated saliva or culture media and dried on stainless steel coupons. Ninety percent of infectious virus was inactivated every 6.8 minutes in simulated saliva and every 14.3 minutes in culture media when exposed to simulated sunlight representative of the summer solstice at 40°N latitude at sea level on a clear day. Significant inactivation also occurred, albeit at a slower rate, under lower simulated sunlight levels. The present study provides the first evidence that sunlight may rapidly inactivate SARS-CoV-2 on surfaces, suggesting that persistence, and subsequently exposure risk, may vary significantly between indoor and outdoor environments. Additionally, these data indicate that natural sunlight may be effective as a disinfectant for contaminated nonporous materials.

Airborne SARS-CoV-2 Is Rapidly Inactivated by Simulated Sunlight.

Aerosols represent a potential transmission route of COVID-19. This study examined effect of simulated sunlight, relative humidity, and suspension matrix on stability of SARS-CoV-2 in aerosols. Simulated sunlight and matrix significantly affected decay rate of the virus. Relative humidity alone did not affect the decay rate; however, minor interactions between relative humidity and other factors were observed. Mean decay rates (± SD) in simulated saliva, under simulated sunlight levels representative of late winter/early fall and summer were 0.121 ±â€…0.017 min-1 (90% loss, 19 minutes) and 0.306 ±â€…0.097 min-1 (90% loss, 8 minutes), respectively. Mean decay rate without simulated sunlight across all relative humidity levels was 0.008 ±â€…0.011 min-1 (90% loss, 286 minutes). These results suggest that the potential for aerosol transmission of SARS-CoV-2 may be dependent on environmental conditions, particularly sunlight. These data may be useful to inform mitigation strategies to minimize the potential for aerosol transmission.

Understanding Sources of Knowledge for Coaches of Athletes with Intellectual Disabilities.

BACKGROUND: Recent research has investigated development of coaching knowledge; however, less research has investigated the development of coaches who coach athletes with intellectual disabilities. The purpose of this study was to understand how coaches of athletes with intellectual disabilities gain their knowledge. METHOD: Forty-five Special Olympics Canada coaches participated in structured telephone interviews investigating actual and ideal sources of coaching knowledge. Coaching knowledge was categorized across the dimensions of competition, organization and training. RESULTS: Coaches primarily learned by doing and by consulting with coaching peers. Information about ideal sources of coaching knowledge demonstrates that coaches would value structured coaching courses, learning from mentors and from administrative support, in addition to learning on their own and from peers. DISCUSSION: Results suggest that a broader approach to education should be incorporated into coaching athletes with intellectual disabilities. Recommendations for achieving such goals are provided.

Efficacy of ETI-204 monoclonal antibody as an adjunct therapy in a New Zealand white rabbit partial survival model for inhalational anthrax.

Inhalational anthrax is characterized by extensive bacteremia and toxemia as well as nonspecific to mild flu-like symptoms, until the onset of hypotension, shock, and mortality. Without treatment, the mortality rate approaches 100%. Antibiotic treatment is not always effective, and alternative treatments are needed, such as monotherapy for antibiotic-resistant inhalational anthrax or as an adjunct therapy in combination with antibiotics. The Bacillus anthracis antitoxin monoclonal antibody (MAb) ETI-204 is a high-affinity chimeric deimmunized antibody which targets the anthrax toxin protective antigen (PA). In this study, a partial protection New Zealand White (NZW) rabbit model was used to evaluate the protective efficacy of the adjunct therapy with the MAb. Following detection of PA in the blood, NZW rabbits were administered either an antibiotic (doxycycline) alone or the antibiotic in conjunction with ETI-204. Survival was evaluated to compare the efficacy of the combination adjunct therapy with that of an antibiotic alone in treating inhalational anthrax. Overall, the results from this study indicate that a subtherapeutic regimen consisting of an antibiotic in combination with an anti-PA MAb results in increased survival compared to the antibiotic alone and would provide an effective therapeutic strategy against symptomatic anthrax in nonvaccinated individuals.

Breathing Techniques Affect Female but Not Male Hip Flexion Range of Motion.

Two protocols were undertaken to help clarify the effects of breathing techniques on hamstrings (hip flexion) range of motion (ROM). The protocols examined effects of breathing conditions on ROM and trunk muscle activity. Protocol 1: Thirty recreationally active participants (15 male, 15 female, 20-25 years) were monitored for changes in single-leg raise (SLR) ROM with 7 breathing conditions before or during a passive supine SLR stretch. Breathing conditions included prestretch inhale, prestretch exhale, inhale-during stretch, exhale-during stretch, neutral, hyperventilation, and hypoventilation before stretch. Protocol 2: Eighteen recreationally active participants (9 male, 9 female, 20-25 years) were monitored for electromyographic (EMG) activity of the rectus abdominus, external obliques, lower abdominal stabilizers, and lower erector spinae while performing the 7 breathing conditions before or during a passive SLR stretch. Control exhibited less ROM (p = 0.008) than the prestretch inhale (7.7%), inhale-during stretch (10.9%), and hypoventilation (11.2%) conditions with females. Protocol 3: Greater overall muscle activity in the prestretch exhale condition was found compared with inhale-during stretch (43.1%↓; p = 0.029) and hypoventilation (51.2%↓; p = 0.049) conditions. As the inhale-during stretch and hypoventilation conditions produced the lowest levels of muscle activity for both sexes and the highest ROM for the females, it can be assumed that both mechanical and neural factors affect female SLR ROM. Lesser male ROM might be attributed to anatomical differences such as greater joint stiffness. The breathing techniques may have affected intra-abdominal pressure, trunk muscle cocontractions, and sympathetic neural activity to enhance female ROM.

Local people's perceptions of international clinical placements in low- and middle-income countries: A literature review.

Background: Student nurses in high-income countries are increasingly taking opportunities to undertake international clinical placements in low- and middle-income countries as part of their pre-registration studies. Objectives: This review aimed to identify and evaluate existing research explores what local people in low- and middle-income countries think of international clinical placements taking place in their localities. This includes a range of local stakeholders, such as clinicians (including midwives, nurses, physicians, pharmacists, and academics), healthcare students (from any discipline), patients, carers, and community members. Considering the limited research focused specifically on local individuals exposed to nursing students, we sought to review the wider research exploring the perceptions of local people in low- and middle-income countries who have been exposed to any type of travelling pre-registration healthcare students. The aim of this review was to assess the size and scope of available research literature, establish research priorities, and provide generalizable findings relevant to all international clinical placements, including those undertaken by nursing students. Design: Electronic databases were used to search for published results of previous research, including PubMed, Embase, Web of Science, CINAHL, Medline Ovid, and the Cochrane Library. Thirteen peer-reviewed articles were included after the screening process. The results of the original studies were analysed using a thematic synthesis. Results: Themes identified included learning (with subthemes of travelling students learning from local people, local people learning from travelling students, and optimising learning), prestige, travelling student behaviour, and resource use (with subthemes of enhancing resources, draining resources and improvements via partnership working). Whilst challenges and drawbacks of international clinical placements were identified, on balance, local people across all the studies were positive about receiving travelling students and keen for this to continue. Conclusion: This work has found that the current body of research exploring perceptions of international clinical placements was heavily focused on local clinicians who have been exposed to travelling medical students. Some of the themes identified may be generalisable to all stakeholders of all types of international clinical placements. These include the central concern regarding reciprocity and the desire that international placements should be beneficial for all involved, rather than solely the travelling student. However, further research is required to understand how other types of placements, such as nursing placements, are viewed by other local people (e.g., patients).

Aerosol Particle Size Influences the Infectious Dose and Disease Severity in a Golden Syrian Hamster Model of Inhalational COVID-19.

Background: Significant evidence suggests that SARS-CoV-2 can be transmitted via respiratory aerosols, which are known to vary as a function of respiratory activity. Most animal models examine disease presentation following inhalation of small-particle aerosols similar to those generated during quiet breathing or speaking. However, despite evidence that particle size can influence dose-infectivity relationships and disease presentation for other microorganisms, no studies have examined the infectivity of SARS-CoV-2 contained in larger particle aerosols similar to those produced during coughing, singing, or talking. Therefore, the aim of the present study was to assess the influence of aerodynamic diameter on the infectivity and virulence of aerosols containing SARS-CoV-2 in a hamster model of inhalational COVID-19. Methods: Dose-response relationships were assessed for two different aerosol particle size distributions, with mass median aerodynamic diameters (MMADs) of 1.3 and 5.2 µm in groups of Syrian hamsters exposed to aerosols containing SARS-CoV-2. Results: Disease was characterized by viral shedding in oropharyngeal swabs, increased respiratory rate, decreased activity, and decreased weight gain. Aerosol particle size significantly influenced the median doses to induce seroconversion and viral shedding, with both increasing ∼30-fold when the MMAD was increased. In addition, disease presentation was dose-dependent, with seroconversion and viral shedding occurring at lower doses than symptomatic disease characterized by increased respiratory rate and decreased activity. Conclusions: These results suggest that aerosol particle size may be an important factor influencing the risk of COVID-19 transmission and needs to be considered when developing animal models of disease. This result agrees with numerous previous studies with other microorganisms and animal species, suggesting that it would be generally translatable across different species. However, it should be noted that the absolute magnitude of the observed shifts in the median doses obtained with the specific particle sizes utilized herein may not be directly applicable to other species.

Natural history of inhalation melioidosis in rhesus macaques (Macaca mulatta) and African green monkeys (Chlorocebus aethiops).

Burkholderia pseudomallei, the causative agent of melioidosis, is recognized as a serious health threat due to its involvement in septic and pulmonary infections in areas of endemicity and is recognized by the Centers for Disease Control and Prevention as a category B biothreat agent. An animal model is desirable to evaluate the pathogenesis of melioidosis and medical countermeasures. A model system that represents human melioidosis infections is essential in this process. A group of 10 rhesus macaques (RMs) and 10 African green monkeys (AGMs) was exposed to aerosolized B. pseudomallei 1026b. The first clinical signs were fever developing 24 to 40 h postexposure followed by leukocytosis resulting from a high percentage of neutrophils. Dyspnea manifested 2 to 4 days postexposure. In the AGMs, an increase in interleukin 1ß (IL-1ß), IL-6, IL-8, gamma interferon (IFN-γ), and tumor necrosis factor alpha (TNF-α) was observed. In the RMs, IL-1ß, IL-6, and TNF-α increased. All the RMs and AGMs had various degrees of bronchopneumonia, with inflammation consisting of numerous neutrophils and a moderate number of macrophages. Both the RMs and the AGMs appear to develop a melioidosis infection that closely resembles that seen in acute human melioidosis. However, for an evaluation of medical countermeasures, AGMs appear to be a more appropriate model.

Comparison of Dose-Response Relationships for Two Isolates of SARS-CoV-2 in a Nonhuman Primate Model of Inhalational COVID-19.

Background: As the COVID-19 pandemic has progressed, numerous variants of SARS-CoV-2 have arisen, with several displaying increased transmissibility. Methods: The present study compared dose-response relationships and disease presentation in nonhuman primates infected with aerosols containing an isolate of the Gamma variant of SARS-CoV-2 to the results of our previous study with the earlier WA-1 isolate of SARS-CoV-2. Results: Disease in Gamma-infected animals was mild, characterized by dose-dependent fever and oronasal shedding of virus. Differences were observed in shedding in the upper respiratory tract between Gamma- and WA-1-infected animals that have the potential to influence disease transmission. Specifically, the estimated median doses for shedding of viral RNA or infectious virus in nasal swabs were approximately 10-fold lower for the Gamma variant than the WA-1 isolate. Given that the median doses for fever were similar, this suggests that there is a greater difference between the median doses for viral shedding and fever for Gamma than for WA-1 and potentially an increased range of doses for Gamma over which asymptomatic shedding and disease transmission are possible. Conclusions: These results complement those of previous studies, which suggested that differences in exposure dose may help to explain the range of clinical disease presentations observed in individuals with COVID-19, highlighting the importance of public health measures designed to limit exposure dose, such as masking and social distancing. The dose-response data provided by this study are important to inform disease transmission and hazard modeling, as well as to inform dose selection in future studies examining the efficacy of therapeutics and vaccines in animal models of inhalational COVID-19.

The influence of temperature, humidity, and simulated sunlight on the infectivity of SARS-CoV-2 in aerosols.

Recent evidence suggests that respiratory aerosols may play a role in the spread of SARS-CoV-2 during the ongoing COVID-19 pandemic. Our laboratory has previously demonstrated that simulated sunlight inactivated SARS-CoV-2 in aerosols and on surfaces. In the present study, we extend these findings to include the persistence of SARS-CoV-2 in aerosols across a range of temperature, humidity, and simulated sunlight levels using an environmentally controlled rotating drum aerosol chamber. The results demonstrate that temperature, simulated sunlight, and humidity are all significant factors influencing the persistence of infectious SARS-CoV-2 in aerosols, but that simulated sunlight and temperature have a greater influence on decay than humidity across the range of conditions tested. The time needed for a 90% decrease in infectious virus ranged from 4.8 min at 40 °C, 20% relative humidity, and high intensity simulated sunlight representative of noon on a clear day on the summer solstice at 4°N latitude, to greater than two hours under conditions representative of those expected indoors or at night. These results suggest that the persistence of infectious SARS-CoV-2 in naturally occurring aerosols may be affected by environmental conditions, and that aerosolized virus could remain infectious for extended periods of time under some environmental conditions. The present study provides a comprehensive dataset on the influence of environmental parameters on the survival of SARS-CoV-2 in aerosols that can be utilized, along with data on viral shedding from infected individuals and the inhalational infectious dose, to inform future modeling and risk assessment efforts.

Integration of an evidence-based tobacco cessation program into a substance use disorders program to enhance equity of treatment access for northern, rural, and remote communities.

Integrating tobacco cessation interventions into substance use disorder (SUD) programs is recommended, yet few are implemented into practice. This translational research implementation study was designed to integrate an evidence-based tobacco cessation intervention into a 2-week hospital outpatient SUD program that served a rural municipality and 33 remote Indigenous communities. Objectives included determining tobacco use prevalence, intervention uptake, and staffing resources required for intervention delivery. A series of 1-hr tobacco and health/well-being interactive education and behavior-change groups were developed for the SUD program to create a central access point to offer an evidence-based, intensive tobacco cessation intervention that included an initial counseling/planning session and nine post-SUD treatment follow-ups (weekly month 1; biweekly month 2; and 3, 6, and 12 months). Group sign-in data included age, gender, community, tobacco use, and interest in receiving tobacco cessation help. Thirty-two groups (April 2018 to February 2019) were attended by 105 people from 22 communities-56% were female, mean age = 30.9 (±7.3; 93% <45 years), 86% smoked, and 38% enrolled in the intensive tobacco cessation intervention. The age-standardized tobacco use ratio was two times higher than would be expected in the general rural population in the region. Average staff time to provide the intervention was 1.5-2.5 hr/week. Results showed that a Healthy Living group integrated into SUD programming provided a forum for tobacco education, behavior-change skills development, and access to an intensive tobacco cessation intervention for which enrollment was high yet the intervention could be delivered with only a few staff hours a week.

Identifying important factors for older adults' physical activity participation across individual/group, structured/unstructured contexts.

Most Canadian older adults do not meet physical activity recommendations. Researchers have investigated participation barriers and facilitators, with little consideration given to how specific factors influence activity participation for older adults. The purpose of this study was to identify unique factors that influence older adults' activity selection and to determine in which type of setting they are preferred. Using a two-phase methodology, identification of 25 factors affecting participation was followed by 45 older adults ranking the factors within four categories of activities: individual unstructured, group unstructured, individual structured, and group structured. Phase 1 analysis ranked each factor within each category. Further analysis found that there was a statistical difference between categories, indicating that older adults found different factors important, depending on the category of physical activity in question. This led to phase 2 analyses which identified three levels of factor groupings including the following factors: level A: fun, satisfaction, commitment, and energize; level B: safety, learning, awareness, internal motivation, and productive; and level C: meaningful contribution, intensity, and motivation. Additionally, some factors which were not identified in all categories were identified as unique to certain categories. These included creativity, hobbies, meaningful contribution, spiritual, competence, interaction casual, regularly scheduled, competition, self-efficacy physical, and team. This information can be used by individuals as well as program providers to nurture these factors within physical activity programs, which may lead to increased participation in this age cohort.