Safety and immunogenicity of a recombinant COVID-19 vaccine (Sf9 cells) in healthy population aged 18 years or older: two single-center, randomised, double-blind, placebo-controlled, phase 1 and phase 2 trials.

COVID-19 vaccines from multiple manufacturers are needed to cope with the problem of insufficient supply. We did two single-center, randomised, double-blind, placebo-controlled phase 1 and phase 2 trials to assess the safety, tolerability and immunogenicity of a recombinant COVID-19 vaccine (Sf9 cells) in healthy population aged 18 years or older in China. Eligible participants were enrolled, the ratio of candidate vaccine and placebo within each dose group was 3:1 (phase 1) or 5:1 (phase 2). From August 28, 2020, 168 participants were sequentially enrolled and randomly assigned to receive the low dose vaccine, high dose vaccine or placebo with the schedule of 0, 28 days or 0, 14, 28 days in phase 1 trial. From November 18, 2020, 960 participants were randomly assigned to receive the low dose vaccine, high dose vaccine or placebo with the schedule of 0, 21 days or 0, 14, 28 days in phase 2 trial. The most common solicited injection site adverse reaction within 7 days in both trials was pain. The most common solicited systematic adverse reactions within 7 days were fatigue, cough, sore throat, fever and headache. ELISA antibodies and neutralising antibodies increased at 14 days, and peaked at 28 days (phase 1) or 30 days (phase 2) after the last dose vaccination. The GMTs of neutralising antibody against live SARS-CoV-2 at 28 days or 30 days after the last dose vaccination were highest in the adult high dose group (0, 14, 28 days), with 102.9 (95% CI 61.9-171.2) and 102.6 (95% CI 75.2-140.1) in phase 1 and phase 2 trials, respectively. Specific T-cell response peaked at 14 days after the last dose vaccination in phase 1 trial. This vaccine is safe, and induced significant immune responses after three doses of vaccination.

Index and First-Generation Cases in a COVID-19 Outbreak — Jilin Province, China, 2021

What is already known on this topic? Contact tracing and testing with isolated medical care of identified cases is a key strategy for interrupting chains of transmission of COVID-19 and reducing mortality associated with COVID-19. At the early phases of the COVID-19 pandemic, due to test capacity limitations, case finding often started from suspected cases. What is added by this report? The index patient infected 74 individuals who were close contacts that were identified through contact tracing, and exposed individuals were monitored in quarantine with daily polymerase chain reaction (PCR) testing. All individuals were asymptomatic initially, but all PCR-positive individuals eventually developed symptoms. Infectivity was documented up to 8 days before being confirmed as a symptomatic case, approximately 4 days before turning PCR positive. What are the implications for public health practice? During an outbreak, we suggest tracing close contacts from both PCR-positive individuals and suspected cases, rather than from suspected cases alone. Due to the long period of infectivity before turning PCR positive or developing symptoms, close contacts that had contact with a newly PCR positive case within 4 days should be judged as at risk of being infected;close contacts that had contact within 8 days of a newly symptomatic case should be judged as at risk being infected.

COVID-19 patients with hypertension are at potential risk of worsened organ injury.

In less than 6 months, COVID-19 spread rapidly around the world and became a global health concern. Hypertension is the most common chronic disease in COVID-19 patients, but its impact on these patients has not been well described. In this retrospective study, 82 patients diagnosed with COVID-19 were enrolled, and epidemiological, demographic, clinical, laboratory, radiological and therapy-related data were analyzed and compared between COVID-19 patients with (29 cases) or without (53 cases) hypertension. The median age of the included patients was 60.5 years, and the cohort included 49 women (59.8%) and 33 (40.2%) men. Hypertension (31 [28.2%]) was the most common chronic illness, followed by diabetes (16 [19.5%]) and cardiovascular disease (15 [18.3%]). The most common symptoms were fatigue (55 [67.1%]), dry cough (46 [56.1%]) and fever ≥ 37.3 °C (46 [56.1%]). The median time from illness onset to positive RT-PCR test was 13.0 days (range 3-25 days). There were 6 deaths (20.7%) in the hypertension group and 5 deaths (9.4%) in the nonhypertension group, and more hypertensive patients with COVID-19 (8 [27.6%]) than nonhypertensive patients (2 [3.8%]) (P = 0.002) had at least one comorbid disease. Compared with nonhypertensive patients, hypertensive patients exhibited higher neutrophil counts, serum amyloid A, C-reactive protein, and NT-proBNP and lower lymphocyte counts and eGFR. Dynamic observations indicated more severe disease and poorer outcomes after hospital admission in the hypertension group. COVID-19 patients with hypertension have increased risks of severe inflammatory reactions, serious internal organ injury, and disease progression and deterioration.