CDC releases report on the description and analysis of the epidemiological characteristics of 72,000 cases

The largest analysis of new coronary pneumonia cases to date has emerged. Recently, the Epidemiology Group of the China Center for Disease Control and Prevention (CDC) Emergency Response Mechanism for New Coronary Virus pneumonia released a report describing and analyzing the epidemiological characteristics of a total of 72,000 cases reported in mainland China as of February 11, 2020.

The report is entitled “Epidemiological Characteristics Analysis of New Coronavirus Pneumonia” (Vital Surveillances: The Epidemiological Characteristics of an Outbreak of 2019 Corona Novelviru The way s Diseases’ academic papers are presented: the Chinese version appears in the latest issue of the Chinese Journal of Epidemiology on February 17th, and the English version is published in the Chinese CDC Weekly.

Analysis using cross-sectional research methods

In terms of research methods, the paper uses cross-sectional studies (refers to the collection and description of the characteristics of the population and disease or health status on an individual basis for a certain range of populations at a given time, and is the most widely used method in describing epidemiology). The paper also refers to the STROBE Statement (i.e., the Quality Statement of Observational Studies in Epidemiology, the primary purpose of which is to improve the quality of medical reports through regulation).

In the paper, the team analyzed the epidemiological curve of patient characteristics, mortality, age distribution and sex ratio, time-space characteristics of disease transmission, and all cases, cases outside Hubei Province, and medical personnel cases, using descriptive statistical cases, using demographic and clinical special seistic consultations of descriptive statistical cases.

Basic characteristics of 72,000 cases

As of February 11, 2020, a total of 72,314 cases of new coronary pneumonia had been reported in the Mainland of China, of which 44,672 cases (61.8%), 16,186 suspected cases (22.4%), 10567 clinical diagnoses (14.6%), and 889 cases of asymptomatic (1.2%).

After analysis, the age of patients was mainly concentrated between 30 and 69 years of age (77.8%), and the proportion of mild patients was 80.9% (the figure below shows the age distribution characteristics of confirmed cases in Wuhan, Hubei and the whole country).

CDC releases report on the description and analysis of the epidemiological characteristics of 72,000 cases

In addition, the team conducted a systematic analysis of the subject’s gender, occupation, province, Wuhan exposure history, underlying diseases, severity (figure below), the main data include:

51.4% of the patients were male, 48.6% were female, the proportion of men was slightly higher than that of women, and the sex orientation was not obvious;

Retirees had the highest fatality rate, at 5.1 per cent;

The confirmed cases in Hubei Province accounted for 74.7%, and the fatality rate of crude disease was 2.9%;

Wuhan has a history of exposure cases accounted for 85.8%;

The fatality rate was 0.9% in patients without basic diseases, while the fatality rate for underlying diseases was much higher: cardiovascular disease 10.5%, diabetes 7.3%, chronic respiratory disease s.3%, hypertension 6.0%, cancer 5.6%;

Mild/moderate disease accounted for 80.9%, severe cases 13.8%, critical cases 4.7%, and the fatality rate of critical cases was 49%, with a fatality density of 0.325, i.e. an average risk of death per critical case observed for 10 days was 0.325.

CDC releases report on the description and analysis of the epidemiological characteristics of 72,000 cases按照发病时间绘制流行曲线

In addition, the team mapped the epidemic curve based on the incidence of the case , from a small pattern of exposure transmission in December 2019 to a pattern of diffusion in January 2020.

As shown in the figure below, December 2019 is in the early stages of the outbreak, with the virus spreading on a small scale, with only 0-22 cases per day. The number of confirmed cases then rose rapidly from the beginning of January, reaching its first peak on 24-28 January and then slowly declining. However, on 1 February, the single-day incidence was abnormally high and gradually decreased. However, the confirmed cases did not peak until 4 February.

CDC releases report on the description and analysis of the epidemiological characteristics of 72,000 cases

As a result, the paper notes that the rapid increase in the number of cases and the growing number of people spreading evidence that the virus is more contagious than SARS-CoV and MERS-CoV.

3019 health care workers infected

In addition, the paper also made statistical analysis on the diagnosis, serious illness and death of medical personnel.

CDC releases report on the description and analysis of the epidemiological characteristics of 72,000 cases

According to the analysis, the peak of the medical staff’s illness is on 28 January. Of the 3,019 infected medical staff in 422 medical institutions that provide dyed patients, 1716 were confirmed and 5 died.

At the same time, 1688 confirmed cases with severe conditions were analyzed, with 1080 cases in Wuhan, accounting for 64.0% of the total number of cases among medical personnel in the country, 394 cases (23.3%) in other areas except Wuhan, and 214 cases (12.7%) in 30 provinces (regions/cities) in the country except Hubei.

It is worth noting that the researchers analyzed the cause of the health care infection may be caused by non-occupational exposure. In fact, the number of medical personnel infected by the National Health and Reform Commission was more than 1,700, while the data in this paper was more than 3,000.

In this regard, the National Health and Health Commission’s Deputy Director-General of the Medical Administration and Hospital Authority, Jo Yahui, said:

The CDC’s health care reporting data comes from a direct reporting system that only shows the identity of infected cases and whether they are infected. This means that more than 3,000 people were infected as health care providers. Some health care workers are infected with the new coronary pneumonia virus in hospitals and at work, while others may be infected with the new coronary pneumonia virus at home or in the community.

Taken together, we can conclude that although the new coronavirus is highly contagious, the majority of patients have mild symptoms and overall low fatality rates. At the same time, according to the above-mentioned prevalence curve (this study is the first to describe the prevalence curve of new coronary pneumonia), it can be seen that the conclusions of this paper are consistent with a number of previous investigations and findings related to the new coronavirus.

There is no doubt that as more and more research data become public, the epidemic will be viewed in a more comprehensive and scientific light.