Today (December 31), The team of Academician Chen Saijuan of Shanghai Jiao Tong University School of Medicine and the team of Fan Xiaohong of Shanghai Public Health Center jointly released new research results of the two teams' cooperation - assessing the epidemic trend of new crown infection in the autumn and winter of 2022. This research result was recently published in Frontiers of Medicine in the form of a paper "Primary assessment of the diversity of Omicron sublineages and the epidemiologic features of autumn/winter 2022 COVID-19 wave in Chinese mainland".
On December 26, 2022, the country officially promulgated the " Overall Plan for Implementing "Category B and B Controls" for New Coronavirus Infections , which will be implemented from January 8, 2023. In order to evaluate the domestic transmission mode of Omicron strain after adjusting epidemic prevention measures, the possible proportion of severe cases among symptomatic infected people, and the trend of this wave of epidemic in large cities and rural areas in the central and western regions, Chen Saijuan's team and Fan Xiaohong's team jointly tackled key problems to analyze the types of Omicron subtypes currently prevalent in the country, the proportion of severe and critical patients among infected and hospitalized patients, and used mathematical modeling to simulate and predict the trend of the epidemic.
Chen Saijuan said that among the people who have recently developed symptoms of new coronavirus infection, severe cases are mainly concentrated in the elderly with underlying diseases. New Year's Day and Spring Festival are approaching, and rural areas with relatively weak medical resources need to pay special attention.
The main popular strains are BF.7, BA.5.2, BQ.1, and XBB. No new mutant strain
virus strain type has been found, which is one of the topics of greatest concern to the domestic public recently. The research team conducted genome sequencing on 378 randomly selected samples from patients admitted to the Shanghai Public Health Center during the autumn and winter of 2022, and obtained 369 high-quality new coronavirus full genome sequences.
The picture shows the situation of patients with different strains released by the research team. Photo courtesy of the research team
The research team found through molecular evolutionary tree analysis that 369 high-quality viral genomes contained 30 influenza viruses recorded in the Global Initiative for Sharing All Influenza Data (GISAID) database. Among Micron subtype strains, 355 (95.95%) genome sequences are concentrated in 5 Micron sublineages. The main strains include BF.7 and BA.5.2 that have been reported to be popular in Beijing and Guangzhou, and BQ.1 and XBB that have recently appeared in Europe and the United States.
combined with the travel history and infection contact history of infected people, proved that people with a history of contact with the epidemic in Beijing or Guangzhou mainly carry BF.7 and BA.5.2 substrains respectively; infected people entering Shanghai from overseas mainly carry BQ.1 and XBB; among local infected people in Shanghai, in addition to BA.5.2, there are also multiple Omicron substrains that account for a relatively high proportion. No new coronavirus variants have been found in these results.
html Among the 15,706 infected people, 173 are in severe or critical condition. The elderly and male are at higher risk.
As the task of fighting against the new coronavirus infection has shifted to Focusing on preventing and treating severe cases, the research team analyzed the changes in the number of severe/critically ill patients and the total number of infected people in this wave of the epidemic based on public information as of November 29, 2022, and found that the number of severe/critically ill patients increased with the increase in the number of infected people, with the proportion reaching 0.035%.
According to general rules, high-risk groups evolve into severe and critical patients 2-3 weeks after admission. Therefore, the research team analyzed the clinical evolution of 5,706 symptomatic new coronavirus infection patients admitted to the Shanghai Public Health Center from September 1, 2022 to December 26, 2022. After comprehensive medical observation and diagnosis, 5,533 of the patients showed mild and common symptoms. type (96.97% in total), and the remaining 173 patients progressed to severe/critical illness (3.03% in total), including 20 patients with only COVID-19 infection (0.35%) and 153 patients with underlying diseases aggravated by COVID-19 infection (2.68% in total).
In addition, older patients (over 55-60 years old) and male patients have a significantly higher risk of developing severe/critical illness.
Between New Year's Day and the Spring Festival, the new crown epidemic will mainly affect rural areas and small and medium-sized urban areas.
The research team also used mathematical models to initially predict the direction of the Omikeron epidemic. Based on previous infected person data from routine nucleic acid testing in Beijing, Guangzhou, Shanghai, Chongqing and other places, a mathematical model was established to simulate the change curve of the number of infected people, and the recent epidemic development trend was evaluated and predicted. It was initially determined that the number of infected people in this round of Omicron epidemic was coming to an end around New Year's Day in 2023 in the above-mentioned major cities.
The picture shows the proportion of critically ill patients analyzed by the research team. Picture provided by the research team
However, mathematical simulation analysis based on data from the main urban area and suburbs of Chongqing suggests that the peak of the epidemic is delayed in the suburbs, and the peak of infection will be significantly enhanced during the Spring Festival travel period due to the accelerated spread of the epidemic. For Sichuan, Shaanxi, Gansu, Qinghai and other provinces, we predict the progress of the epidemic among people excluding provincial capital cities. It is estimated that the peak infection peak in rural and small and medium-sized urban areas will appear in mid-to-late January 2023. Due to Spring Festival travel, these peaks may also arrive earlier. Based on the above research results, the
team analyzed that with the changes in the transmission route of virus caused by the evolution of the epidemic, multiple Omicron subtypes are spreading simultaneously in the country; among people who have recently developed symptoms of new coronavirus infection, severe cases are mainly concentrated in the elderly with underlying diseases; after New Year's Day and the Spring Festival, the new coronavirus epidemic will mainly affect rural areas and small and medium-sized towns.
What deserves special attention is that domestic rural areas and small and medium-sized urban areas are relatively scarce in medical resources, and there are a large number of elderly people and people with underlying diseases; the mobility of urban and rural populations during the Spring Festival will greatly affect the trend of the epidemic.
Therefore, the team suggested that there is an urgent need to launch an emergency plan for the spread of the Omicron epidemic to rural areas, allocate more medical resources to rural grassroots, prepare emergency use licenses for effective drugs and new vaccines, and do a good job in the production, storage, distribution and clinical rational use of specific anti-COVID-19 drugs, auxiliary drugs, and traditional Chinese medicines with proven efficacy; implement classified and stratified treatment to strengthen the ability to treat severe cases in small and medium-sized towns; continue to make good use of non-pharmaceutical public health Hygiene measures (wearing N95 masks in indoor spaces, maintaining social distance, appropriately increasing the frequency of public transportation to avoid overcrowding, etc.), strive to reduce the peak of the epidemic and relieve the heavy pressure on the medical system and medical staff; continue to fully immunize high-risk groups, and start the fourth immune booster shot for high-risk groups; strengthen the popularization of prevention and control knowledge and skills in individual households, do a good job in health publicity and risk communication, protect the lives and health of the people, especially those in need, and ensure that our country can smoothly emerge from the epidemic.
(Source: China Youth Daily )
Editor: Cheng Qihang
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-