- JAMA: Wuhan public health intervention significantly controls the large-scale outbreak of new coronary pneumonia
On April 10, 2020, Wu Tangchun, Hua Sheng University of Science and Technology, Wei Sheng, and Lin Xihong of Harvard University published a newsletter entitled "Association of Public Health Interventions with the Epidemiology of the COVID-19 Outbreak in Wuhan, China" online in the top medical journal JAMA. The research paper found that among the 32,583 laboratory-confirmed COVID-19 cases, the median age of female patients was 56.7 years and that of females was 16,817 (51.6%). The daily confirmed case rate peaks in the third stage (traffic restrictions and family segregation stage), and then decreases in geographic areas, gender and age groups, except for children and adolescents, whose confirmed case rate continues to rise.
Throughout the period, the daily confirmed case rate of local health care workers (130.5 per million people) was higher than that of the general population (41.5 per million people). During these five periods, the proportion of severe and critical cases fell from 53.1% to 10.3%. The risk of severity increases with age: the risk of serious or critical illness in the elderly (≥80 years old) is higher (proportion is 41.3%) compared with the population in the 20-39 age group (the proportion of severe and critical cases is 12.1%).
In summary, a series of multifaceted public health interventions are related in time to improved control of the COVID-19 outbreak in Wuhan, China. These findings may contribute to public health policies in other countries and regions.
- NEJM: Large-scale clinical trial is released, Radecivir can treat severe patients: 68% of patients have observed improvement in clinical symptoms
On April 10, 2020, Jonathan Grein and others published a research paper titled "Compassionate Use of Remdesivir for Patients with Severe Covid-19" online in the top international medical journal NEJM. The study analyzed data from 53 critically ill patients. 22 in the US, 22 in Europe, and 9 in Japan. At baseline, 30 patients (57%) were receiving mechanical ventilation, and 4 (8%) were undergoing extracorporeal membrane oxygenation. During the 18-day median follow-up period, 36 patients (68%) had improved oxygen support levels, and 17 of 30 (57%) patients who received mechanical ventilation had extubated the tube. A total of 25 patients (47%) were discharged and 7 patients (13%) died; among patients receiving invasive ventilation, the mortality rate was 18% (6 out of 34), while patients not receiving invasive ventilation 5% (1 out of 19).
In general, among patients receiving sympathetic use of remdesivirr (reduxivir), clinical improvement was observed in 36 of 53 patients (68%). The measurement of efficacy will require randomized, placebo-controlled trials of remdesivir treatment.
- Significant progress made by in the field of epidemiology and propagation dynamics of coronavirus disease (COVID-19).
"The Lancet Infectious Diseases" recently published the important progress made by Yu Hongjie's group at the School of Public Health of Fudan University in the field of epidemiology and transmission dynamics of coronavirus disease (COVID-19) in 2019. The study aims to explain the epidemiological characteristics and dynamic changes of transmission dynamics parameters of COVID-19 in areas outside Hubei Province, mainland China. The article emphasizes that the effectiveness of prevention and control measures is only applicable when the measures are in place. If the existing public health interventions are relaxed or major changes in crowd behavior occur, it may lead to increased follow-up transmission. Given that COVID-19 is spreading globally, the results of this study not only provide important scientific evidence for China to formulate prevention and control strategies, but also provide important references for other countries in the progress of the epidemic.
The results of the study show that the median age of the cases is 44 years old. As the epidemic progresses, the proportion of minors and elderly people aged 65 and above has increased. Although about 20% of China's total population is minors, the proportion of minors in confirmed cases is only 5%. The above results do not yet indicate that minors have a lower susceptibility risk or have a lighter clinical manifestation after infection. Because the epidemic is due to the 2020 winter vacation and the Chinese New Year, schools in China are closed. The reduction in the number of school-age children may be related to a lower risk of infection, but further research is still needed.
The average time between case onset and admission was shortened from 4.4 days before January 27 (95% CI: 0.0-14.0) to 2.6 days from January 28 to February 17 (95% CI: 0.0-9.0). The time from onset to admission and isolation has gradually shortened, reflecting the faster action of governments at all levels to control the epidemic. The average incubation period is 5.2 days (95% CI: 1.8-12.4), and the 95% quantile (10.5 days) indicates that tracking and medical observation of close contacts is very important for the detection of cases with a longer incubation period. The average intergenerational interval is 5.1 days (95% CI: 1.3-11.6), which is shorter than the estimated intergenerational interval of early cases in Wuhan in the previous studies (7.5 days). The shorter intergenerational interval outside Hubei Province may be related to the shorter interval from onset to admission. The average intergenerational interval is shorter than the incubation period, indicating that the case may be infectious before symptoms appear.
Andrew S Azman of the Johns Hopkins University Bloomberg School of Public Health and Francisco J Luquero of Epicentre, France, under the title "From China: Hope and Experience in Controlling COVID-19", wrote an expert review for this study, stating: " Yu Hongjie's group used public data to answer the key epidemiological characteristics of COVID-19 in China, and found that the effective reproduction index of nine severely epidemic areas outside Hubei Province fell below the epidemic threshold by the end of January 2020, effectively slowing the epidemic of local transmission. The author also found that the incubation period and the intergenerational interval have a similar length of time, indicating that the case is contagious before or shortly after the onset of symptoms. " Transparency and timeliness have surpassed most countries, and rapid data analysis and model research have provided important decision-making basis for other countries in the progress of the epidemic. Based on limited historical information on newly emerging infectious diseases, the Chinese government weighed the economy, social and public health and other aspects, the most stringent prevention and control measures have been adopted the country ’s similar measures have provided important advance experience. The results of this study have increased confidence in the possibility of the epidemic being quickly controlled globally. "