Azacytidine targeting SARS-CoV-2 viral RNA as a potential treatment for COVID-19 (preprint)

The COVID-19 pandemic is a global health disaster. Moreover, emerging mutated virus strains present an even greater challenge for existing vaccines and medications. One possible solution is to design drugs based on the properties of virus epigenome, which are more common among coronaviruses. Here, we reported an FDA-approved drug for myelodysplastic syndrome, azacytidine (5Aza), limited virus infection and protected mice against SARS-CoV-2. We demonstrated that this antiviral effect is related to 5Aza incorporation into viral RNA, which disrupt m5C RNA methylation modification profile. This work suggests that targeting viral epigenomes is a viable therapeutic strategy, potentially opening new pathways for treating COVID-19.

Distinct Regimes of O3 Response to COVID-19 Lockdown in China

Restrictions on human activities remarkably reduced emissions of air pollutants in China during the COVID-19 lockdown periods. However, distinct responses of O3 concentrations were observed across China. In the Beijing–Tianjin–Hebei (BTH) and Yangtze River Delta (YRD) regions, O3 concentrations were enhanced by 90.21 and 71.79% from pre-lockdown to lockdown periods in 2020, significantly greater than the equivalent concentrations for the same periods over 2015–2019 (69.99 and 43.62%, p <0.001). In contrast, a decline was detected (−1.1%) in the Pearl River Delta (PRD) region. To better understand the underlying causes for these inconsistent responses across China, we adopted the least absolute shrinkage and selection operator (Lasso) and ordinary linear squares (OLS) methods in this study. Statistical analysis indicated that a sharp decline in nitrogen dioxide (NO2) was the major driver of enhanced O3 in the BTH region as it is a NOx-saturated region. In the YRD region, season-shift induced changes in the temperature/shortwave radiative flux, while lockdown induced declines in NO2, attributable to the rise in O3. In the PRD region, the slight drop in O3 is attributed to the decreased intensity of radiation. The distinct regimes of the O3 response to the COVID-19 lockdown in China offer important insights into different O3 control strategies across China.

Disease Burden from Coronavirus Disease 2019 Symptoms Among Inpatients at the Temporary Military Hospitals in Wuhan: A Retrospective Multi-Center Cross-Sectional Study (preprint)

Background: Since the advent of the coronavirus disease 2019 (COVID-19) pandemic, in most parts of the world, people are still at risk of the disease. We aimed to establish a set of disability weights (DWs) for COVID-19 symptoms, evaluate the disease burden of inpatients, analyze the characteristics, and influencing factors of the disease. Methods: The symptoms were identified by literature review and medical staff questionnaire. DWs of COVID-19 symptoms were determined by the person-trade-off approach proposed by the World Health Organization. The extracted medical records data of 2,702 randomly selected inpatients with COVID-19 at three temporary military hospitals in Wuhan, China, were analyzed and used to calculate the disability adjusted life years (DALY). Means DALY between gender and age groups were tested by analysis of variance. Multiple line regression models were used to determine the relationship between DALY and age, gender, body mass index, length of stay, symptom duration before admission, and native place. Results: For the DALY of each inpatient, severe expiratory dyspnea and mild cough and sore throat had the highest (0.399) and lowest (0.004) weights, respectively. The average synthetic DALY and daily DALY were 2.29±1.33 and 0.18±0.15 days, respectively. Fever and fatigue contributed the largest DALY at 31.36%; nausea and vomiting, and anxiety and depression contributed the least at 7.05%. There were significant differences between gender and age groups in both synthetic and daily DALY. Age, body mass index, length of stay, and symptom duration before admission were strongly related to both synthetic and daily DALY. Conclusions: COVID-19 and its symptoms could cause heavy disease burden. Although the disease burden was higher among females than in the males; however, their daily disease burdens were similar. Life value differs for different age groups; taking the changing life value with age into account; the disease burden in the younger population was higher than that in the older population. Besides, treatment at the hospitals relieved the disease burden efficiently, while delay in hospitalization could worsen it. Therefore, deployment of adequate medical resources for early hospitalization of patients with moderate or severe symptoms is needed by the public health authority.