(searched for: doi:10.2807/1560-7917.es.2021.26.13.2100333)
Frontiers in Medicine, Volume 9; https://doi.org/10.3389/fmed.2022.828402
Objectives: The clinical outcomes of the Beta (B.1.351) variant of concern (VOC) of the SARS-CoV-2 virus remain poorly understood. In early 2021, northeastern France experienced an outbreak of Beta that was not observed elsewhere. This outbreak slightly preceded and then overlapped with a second outbreak of the better understood VOC Alpha (B.1.1.7) in the region. This situation allowed us to contemporaneously compare Alpha and Beta in terms of the characteristics, management, and outcomes of critically ill patients. Methods: A multicenter prospective cohort study was conducted on all consecutive adult patients who had laboratory confirmed SARS CoV-2 infection, underwent variant screening, and were admitted to one of four intensive care units (ICU) for acute respiratory failure between January 9th and May 15th, 2021. Primary outcome was 60-day mortality. Differences between Alpha and Beta in terms of other outcomes, patient variables, management, and vaccination characteristics were also explored by univariate analysis. The factors that associated with 60-day death in Alpha- and Beta-infected patients were examined with logistic regression analysis. Results: In total, 333 patients (median age, 63 years; 68% male) were enrolled. Of these, 174 and 159 had Alpha and Beta, respectively. The two groups did not differ significantly in terms of 60-day mortality (19 vs. 23%), 28-day mortality (17 vs. 20%), need for mechanical ventilation (60 vs. 61%), mechanical ventilation duration (14 vs. 15 days), other management variables, patient demographic variables, comorbidities, or clinical variables on ICU admission. The vast majority of patients were unvaccinated (94%). The remaining 18 patients had received a partial vaccine course and 2 were fully vaccinated. The vaccinated patients were equally likely to have Alpha and Beta. Conclusions: Beta did not differ from Alpha in terms of patient characteristics, management, or outcomes in critically ill patients. Trial Registration: ClinicalTrials.gov, identifier: NCT04906850.
Infectious Diseases of Poverty, Volume 10, pp 1-13; https://doi.org/10.1186/s40249-021-00901-9
Background The incubation period is a crucial index of epidemiology in understanding the spread of the emerging Coronavirus disease 2019 (COVID-19). In this study, we aimed to describe the incubation period of COVID-19 globally and in the mainland of China. Methods The searched studies were published from December 1, 2019 to May 26, 2021 in CNKI, Wanfang, PubMed, and Embase databases. A random-effect model was used to pool the mean incubation period. Meta-regression was used to explore the sources of heterogeneity. Meanwhile, we collected 11 545 patients in the mainland of China outside Hubei from January 19, 2020 to September 21, 2020. The incubation period fitted with the Log-normal model by the coarseDataTools package. Results A total of 3235 articles were searched, 53 of which were included in the meta-analysis. The pooled mean incubation period of COVID-19 was 6.0 days (95% confidence interval [CI] 5.6–6.5) globally, 6.5 days (95% CI 6.1–6.9) in the mainland of China, and 4.6 days (95% CI 4.1–5.1) outside the mainland of China (P = 0.006). The incubation period varied with age (P = 0.005). Meanwhile, in 11 545 patients, the mean incubation period was 7.1 days (95% CI 7.0–7.2), which was similar to the finding in our meta-analysis. Conclusions For COVID-19, the mean incubation period was 6.0 days globally but near 7.0 days in the mainland of China, which will help identify the time of infection and make disease control decisions. Furthermore, attention should also be paid to the region- or age-specific incubation period. Graphic Abstract
SSRN Electronic Journal; https://doi.org/10.2139/ssrn.3889352
Background: The healthcare workers (HCWs) have been on the frontline in combating the pandemic and were prioritized for vaccination when COVID-19 vaccines became available. Although vaccines effectively prevent infection in most cases, some cases of post-vaccination infections have been reported, raising concerns about vaccine efficacy. This study investigated the efficacy of COVID-19 vaccines in preventing and reducing the severity of post-vaccination infections (PVI) among HCWs. Methods: This observational study examined 28342 vaccinated HCWs with SARS-CoV-2 (symptomatic severe acute respiratory syndrome coronavirus 2) infections during the initial five months of vaccination (January 16-June 15, 2021). They worked at 43 Apollo Group hospitals in 24 Indian cities. PVI was investigated after recombinant ChAdOx nCOV-19 (Recombinant) or the whole virion inactivated Vero cell vaccines were administered. Various parameters were evaluated such as age, sex, time to infection, type of vaccine, infections after a single and two doses, monthly and regional case distribution, clinical severity of infection, hospitalization and intensive care unit (ICU) requirement, and death. Findings: Symptomatic PVIs occurred in a low percentage of vaccinated cohorts (5⸱07%, p<0⸱001), and these were predominantly mild and did not result in hospitalization, ICU admissions (p<0⸱0001), or death. Both vaccines provided similar protection, with PVI incidences of 5⸱11% and 4⸱58%, following ChAdOx nCOV-19 (Recombinant) and the whole virion inactivated Vero cell vaccines, respectively (p50 years significantly contracted more infections(p<0⸱001 and p=0⸱001, respectively). Two-dose vaccination has significantly lower odds of developing PVI (0.83, 95%CI – 0.72 to 0.97). Maximum infections occurred during the peak of the second COVID-19 wave from mid-April to May 2021 (p<0⸱001). No significant difference existed in the infection between sex, vaccine type, and the number of vaccine doses received (p≥0⸱05). Interpretation: PVI occurred in a small percentage of HCWs. Vaccination protected them significantly from the infection but also severe disease. Funding Information: None. Declaration of Interests: None. Ethics Approval Statement: This study was approved by an Ethical Institutional Committee (EIC), and a consent waiver was given by the EIC.