Estimating the restraint of SARS-CoV-2 spread using a conventional medical air-cleaning device: Based on an experiment in a typical dental clinical setting.

OBJECTIVES: Droplets or aerosols loaded with SARS-CoV-2 can be released during breathing, coughing, or sneezing from COVID-19-infected persons. To investigate whether the most commonly applied air-cleaning device in dental clinics, the oral spray suction machine (OSSM), can provide protection to healthcare providers working in clinics against exposure to bioaerosols during dental treatment. METHOD: In this study, we measured and characterized the temporal and spatial variations in bioaerosol concentration and deposition with and without the use of the OSSM using an experimental design in a dental clinic setting. Serratia marcescens (a bacterium) and ΦX174 phage (a virus) were used as tracers. The air sampling points were sampled using an Anderson six-stage sampler, and the surface-deposition sampling points were sampled using the natural sedimentation method. The Computational Fluid Dynamics method was adopted to simulate and visualize the effect of the OSSM on the concentration spatial distribution. RESULTS: During dental treatment, the peak exposure concentration increased by up to 2-3 orders of magnitude (PFU/m3) for healthcare workers. Meanwhile, OSSM could lower the mean bioaerosol exposure concentration from 58.84 PFU/m3 to 4.10 PFU/m3 for a healthcare worker, thereby inhibiting droplet and airborne transmission. In terms of deposition, OSSM significantly reduced the bioaerosol surface concentration from 28.1 PFU/m3 to 2.5 PFU/m3 for a surface, effectively preventing fomite transmission. CONCLUSION: The use of OSSM showed the potential to restraint the spread of bioaerosols in clinical settings. Our study demonstrates that OSSM use in dental clinics can reduce the exposure concentrations of bioaerosols for healthcare workers during dental treatment and is beneficial for minimizing the risk of infectious diseases such as COVID-19.

Effects of short-term and long-term exposure to ambient air pollution and temperature on long recovery duration in COVID-19 patients.

BACKGROUND: The novel coronavirus disease 2019 (COVID-19) has spread rapidly around the world since December 8, 2019. However, the key factors affecting the duration of recovery from COVID-19 remain unclear. OBJECTIVE: To investigate the associations of long recovery duration of COVID-19 patients with ambient air pollution, temperature, and diurnal temperature range (DTR) exposure. METHODS: A total of 427 confirmed cases in Changsha during the first wave of the epidemic in January 2020 were selected. We used inverse distance weighting (IDW) method to estimate personal exposure to seven ambient air pollutants (PM2.5, PM2.5-10, PM10, SO2, NO2, CO, and O3) at each subject's home address. Meteorological conditions included temperature and DTR. Multiple logistic regression model was used to investigate the relationship of air pollution exposure during short-term (past week and past month) and long-term (past three months) with recovery duration among COVID-19 patients. RESULTS: We found that long recovery duration among COVID-19 patients was positively associated with short-term exposure to CO during past week with OR (95% CI) = 1.42 (1.01-2.00) and PM2.5, NO2, and CO during past month with ORs (95% CI) = 2.00 (1.30-3.07) and 1.95 (1.30-2.93), and was negatively related with short-term exposure to O3 during past week and past month with ORs (95% CI) = 0.68 (0.46-0.99) and 0.41 (0.27-0.62), respectively. No association was observed for long-term exposure to air pollution during past three months. Furthermore, increased temperature during past three months elevated risk of long recovery duration in VOCID-19 patients, while DTR exposure during past week and past month decreased the risk. Male and younger patients were more susceptible to the effect of air pollution on long recovery duration, while female and older patients were more affected by exposure to temperature and DTR. CONCLUSION: Our findings suggest that both TRAP exposure and temperature indicators play important roles in prolonged recovery among COVID-19 patients, especially for the sensitive populations, which provide potential strategies for effective reduction and early prevention of long recovery duration of COVID-19.

Assessment of Financial Toxicity Among Patients With Advanced Lung Cancer in Western China.

Background: Lung cancer is the leading source of cancer-caused disability-adjusted life years. Medical cost burden impacts the well-being of patients through reducing income, cutting daily expenses, curtailing leisure activities, and depleting exhausting savings. The COmprehensive Score for Financial Toxicity (COST) was created and validated by De Souza and colleagues. Our study intends to measure the financial burdens of cancer therapy and investigate the link between financial toxicity and health-related quality of life (HRQoL) in an advanced lung cancer population. Methods: Patients aged ≥ 18 years with confirmed stage III to IV lung cancer were eligible. The COST questionnaire verified by de Souza et al. was used to identify financial toxicity. Multivariable linear regression analysis with log transformation univariate analysis and Pearson correlations were used to perform the analysis. Results: The majority of the patients (90.8%, n = 138/152) had an annual income of $50,000 ($7,775). The cohort's insurance situation was as follows: 64.5% of the cohort had social insurance, 20.4% had commercial insurance, and 22.0% had both. Patients who were younger age (50-59, P < 0.001), employed but on sick leave, and had lower income reported increased levels of financial toxicity (P < 0.05). The risk factors for high financial toxicity: (i) younger age (50-59), (ii) <1 month of savings, and (iii) being employed but on sick leave. Increased financial toxicity is moderately correlated with a decrease in QoL. Conclusion: Poorer psychological status and specific demographics are linked to increased financial toxicity (lower COST). Financial toxicity has a modest relationship with HRQoL and may have a clear link with HRQoL measurements.

Perspectives on the flexibility analysis for continuous pharmaceutical manufacturing processes.

Pharmaceutical continuous manufacturing, especially under the context of COVID-19 pandemic, is regarded as an emerging technology that can guarantee the adequate quality assurance and mitigate process risk while guaranteeing the desirable economic performance. Flexibility analysis is one approach to quantitively assess the capability of chemical process to guarantee feasible operation in face of variations on uncertain parameters. The aim of this paper is to provide the perspectives on the flexibility analysis for continuous pharmaceutical manufacturing processes. State-of-the-art and progress in the flexibility analysis for chemical processes including concept evolution, mathematical model formulations, solution strategies, and applications are systematically overviewed. Recent achievements on the flexibility/feasibility analysis of the downstream dosage form manufacturing process are also touched upon. Further challenges and developments in the field of flexibility analysis for novel continuous manufacturing processes of active pharmaceutical ingredients along with the integrated continuous manufacturing processes are identified.

Mapping and role of T cell response in SARS-CoV-2-infected mice.

Virus-specific T cells play essential roles in protection against multiple virus infections, including SARS-CoV and MERS-CoV. While SARS-CoV-2-specific T cells have been identified in COVID-19 patients, their role in the protection of SARS-CoV-2-infected mice is not established. Here, using mice sensitized for infection with SARS-CoV-2 by transduction with an adenovirus expressing the human receptor (Ad5-hACE2), we identified SARS-CoV-2-specific T cell epitopes recognized by CD4+ and CD8+ T cells in BALB/c and C57BL/6 mice. Virus-specific T cells were polyfunctional and were able to lyse target cells in vivo. Further, type I interferon pathway was proved to be critical for generating optimal antiviral T cell responses after SARS-CoV-2 infection. T cell vaccination alone partially protected SARS-CoV-2-infected mice from severe disease. In addition, the results demonstrated cross-reactive T cell responses between SARS-CoV and SARS-CoV-2, but not MERS-CoV, in mice. Understanding the role of the T cell response will guide immunopathogenesis studies of COVID-19 and vaccine design and validation.