The risk of indoor sports and culture events for the transmission of COVID-19.

Nearly all mass gathering events worldwide were banned at the beginning of the COVID-19 pandemic, as they were suspected of presenting a considerable risk for the transmission of SARS-CoV-2. We investigated the risk of transmitting SARS-CoV-2 by droplets and aerosols during an experimental indoor mass gathering event under three different hygiene practices, and used the data in a simulation study to estimate the resulting burden of disease under conditions of controlled epidemics. Our results show that the mean number of measured direct contacts per visitor was nine persons and this can be reduced substantially by appropriate hygiene practices. A comparison of two versions of ventilation with different air exchange rates and different airflows found that the system which performed worst allowed a ten-fold increase in the number of individuals exposed to infectious aerosols. The overall burden of infections resulting from indoor mass gatherings depends largely on the quality of the ventilation system and the hygiene practices. Presuming an effective ventilation system, indoor mass gathering events with suitable hygiene practices have a very small, if any, effect on epidemic spread.

Low-Dose Radiation Therapy for Severe COVID-19 Pneumonia: A Randomized Double-Blind Study.

PURPOSE: The morbidity and mortality of patients requiring mechanical ventilation for coronavirus disease 2019 (COVID-19) pneumonia is considerable. We studied the use of whole-lung low-dose radiation therapy (LDRT) in this patient cohort. METHODS AND MATERIALS: Patients admitted to the intensive care unit and requiring mechanical ventilation for COVID-19 pneumonia were included in this randomized double-blind study. Patients were randomized to 1 Gy whole-lung LDRT or sham irradiation (sham-RT). Treatment group allocation was concealed from patients and intensive care unit clinicians, who treated patients according to the current standard of care. Patients were followed for the primary endpoint of ventilator-free days at day 15 postintervention. Secondary endpoints included overall survival, as well as changes in oxygenation and inflammatory markers. RESULTS: Twenty-two patients were randomized to either whole-lung LDRT or sham-RT between November and December 2020. Patients were generally elderly and comorbid, with a median age of 75 years in both arms. No difference in 15-day ventilator-free days was observed between groups (P = 1.00), with a median of 0 days (range, 0-9) in the LDRT arm and 0 days (range, 0-13) in the sham-RT arm. Overall survival at 28 days was identical at 63.6% (95% confidence interval, 40.7%-99.5%) in both arms (P = .69). Apart from a more pronounced reduction in lymphocyte counts after LDRT (P < .01), analyses of secondary endpoints revealed no significant differences between the groups. CONCLUSIONS: Whole-lung LDRT failed to improve clinical outcomes in critically ill patients requiring mechanical ventilation for COVID-19 pneumonia.

Contingency Plans in a Radiation Oncology Department Amid the 2019-nCoV Outbreak in Switzerland.

The ongoing novel coronavirus (2019-nCoV) pandemic is expected to develop into an unprecedented stress test for health care systems worldwide. This brief report, written from a radiation oncology perspective during the developing outbreak of 2019-nCoV in Switzerland, highlights the challenges identified and measures taken in our department to mitigate risks and ensure continued operations during the outbreak.