Safety of primary immunization using inactivated SARS-CoV-2 vaccine (CoronaVac®) among population aged 3 years and older in a large-scale use: A multi-center open-label study in China.

OBJECTIVE: To evaluate the safety of primary immunization using CoronaVac® among population aged 3 years and above in a large-scale use. METHOD: A multi-center open-label study was carried out in 11 provinces of China. Individuals aged 3 years and older who had no history of COVID-19 vaccination or had received only one dose of CoronaVac® were enrolled in this study. Adults and elderly with or without underlying medical conditions(UMCs) were also recruited. Eligible participants received one or two doses of CoronaVac® with an interval of 28 days. Demographic information, vaccination and the occurrence of adverse events were recorded by participants or guardians using data collection system designed for this study. All adverse events occurred within 6 months after the second dose of vaccination were collected. The incidence of adverse events that cannot be ruled out as being caused by the vaccine were calculated to assess the safety of CoronaVac®. This study is registered with ClinicalTrials. Gov (NCT04911790 and NCT04992208). RESULTS: A total of 162,691 participants have been included in this study and 89.50 % had finished primary immunization. Among adults and elderly, people with UMCs accounted for 25.85 %, with the top five disease being hypertension, diabetes, chronic gastritis, coronary heart disease(CHD) and kidney stone. The overall incidence of adverse reactions (ARs) within 6 months after the second vaccination was 2.70 %, with incidence for children and adolescents, adults, and elderly being 2.03 %, 3.46 %, and 1.90 %, respectively. Most ARs were mild (grade 1). Pain at the injection sites, fatigue, induration/swelling, and headache were the most common symptoms, occurring in 1.64 %, 0.46 %, 0.31 % and 0.24 %, respectively. No serious adverse events related to vaccines were reported. No adverse events of special interest (AESIs) were identified. For children and adolescents, children aged 3-5 years had the highest incidence of ARs of 3.29 %. The incidence of ARs among those aged 18 years and older with and without UMCs were 2.81 % and 2.99 %, respectively, with no statistical significance between two groups(P = 0.089). And people with coronary heart disease had higher AR incidence compared to those with other UMCs, but the most common symptoms was pain at the injection site. CONCLUSION: CoronaVac® is safe in a large-scale use and shows well-tolerance for children and adolescents and people with underlying medical conditions. Further studies need to be conducted to explore the relation of ARs incidence to age or different kinds of UMCs.

A Comparative Study on the Clinical Features of Coronavirus 2019 (COVID-19) Pneumonia With Other Pneumonias.

BACKGROUND: A novel coronavirus (COVID-19) has raised world concern since it emerged in Wuhan, China in December 2019. The infection may result in severe pneumonia with clusters of illness onsets. Its impacts on public health make it paramount to clarify the clinical features with other pneumonias. METHODS: Nineteen COVID-19 and 15 other patients with pneumonia (non-COVID-19) in areas outside of Hubei were involved in this study. Both COVID-19 and non-COVID-19 patients were confirmed to be infected using throat swabs and/or sputa with/without COVID-2019 by real-time RT-PCR. We analyzed the demographic, epidemiological, clinical, and radiological features from those patients, and compared the differences between COVID-19 and non-COVID-19. RESULTS: All patients had a history of exposure to confirmed cases of COVID-19 or travel to Hubei before illness. The median (IQR) duration was 8 (6-11) and 5 (4-11) days from exposure to onset in COVID-19 and non-COVID-19 cases, respectively. The clinical symptoms were similar between COVID-19 and non-COVID-19. The most common symptoms were fever and cough. Fifteen (78.95%) COVID-19 but 4 (26.67%) non-COVID-19 patients had bilateral involvement while 17 COVID-19 patients (89.47%) but 1 non-COVID-19 patient (6.67%) had multiple mottling and ground-glass opacity on chest CT images. Compared with non-COVID-19, COVID-19 presents remarkably more abnormal laboratory tests, including AST, ALT, γ-GT, LDH, and α-HBDH. CONCLUSIONS: The COVID-19 infection has onsets similar to other pneumonias. CT scan may be a reliable test for screening COVID-19 cases. Liver function damage is more frequent in COVID-19 than non-COVID-19 patients. LDH and α-HBDH may be considerable markers for evaluation of COVID-19.