Views: 0 Author: Site Editor Publish Time: 2022-05-23 Origin: Site
Onset characteristics
According to the existing case data, the main manifestations of novel coronavirus pneumonia are fever, dry cough and fatigue, and a few patients have upper respiratory and digestive tract symptoms such as nasal congestion, runny nose and diarrhea. Most severe cases have dyspnea after one week, and the severe cases quickly progress to acute respiratory distress syndrome, septic shock, uncorrectable metabolic acidosis, coagulation dysfunction and multiple organ failure. It is worth noting that patients with severe and critical diseases can have moderate and low fever in the course of disease, or even no obvious fever. Mild patients only showed low fever and slight fatigue, without pneumonia. From the current cases, most of the patients recovered well, and a few were critically ill. The prognosis of the elderly and those with chronic basic diseases is poor. The symptoms of children are relatively mild.
Epidemic characteristics
On March 11th, 2020, who director general Tan Desai said that the COVID-19 had pandemic characteristics.
Tan Desai said at a regular press conference held in Geneva that the spread and severity of the epidemic are deeply worrying.
"Therefore, we assess that the COVID-19 has pandemic characteristics.".
"We have never seen a pandemic caused by coronavirus before. We have never seen a controlled pandemic before," he said
He stressed that describing the COVID-19 as a "pandemic" will not change who's assessment of its threat, "it will not change what who is doing, nor what countries should do".
Novel coronavirus pneumonia is in the early stage of rapid change. China has released the whole genome sequence of the novel coronavirus that causes novel coronavirus pneumonia, which will help global scientists and public health organizations to participate in the research and development of diagnostic reagents and the study of virus pathogenicity.
The National Health Commission has issued No. 1 announcement to include pneumonia infected by novel coronavirus into class B infectious diseases as stipulated in the law on the prevention and control of infectious diseases, but to take measures to prevent and control class A infectious diseases, and to include it into the management of quarantinable infectious diseases.
Epidemic level
On February 28th, 2020, the who daily report on COVID-19 showed that the regional and global risk levels were raised to the highest level "very high", which was consistent with China. Previously, the regional and global risk levels were "high".
On March 11th, 2020 local time, the director general of the World Health Organization Tan Desai announced that according to the assessment, the who believes that the current COVID-19 can be called a global pandemic.
Route of transmission
According to CCTV news, the Shanghai epidemic prevention and control work conference introduced that health and epidemic prevention experts emphasized that the main transmission routes of COVID-19 that can be determined are direct transmission, aerosol transmission and contact transmission. Direct transmission refers to the infection caused by the patient's sneezing, coughing, speaking droplets and direct inhalation of exhaled gas at a close distance; Aerosol transmission refers to that droplets are mixed in the air to form aerosol, which leads to infection after inhalation; Contact transmission refers to the deposition of droplets on the surface of articles, contact with contaminated hands, and then contact with mucous membranes such as oral cavity, nasal cavity and eyes, resulting in infection.
On June 14, 2021, Canadian researchers published a paper in the British journal Nature communication, and found that the novel coronavirus could infect North American deer rats and spread among rats.
On December 1, 2021 local time, the Department of environment and climate change of Canada issued a press release announcing that it was the first time that wild animals in China were infected with novel coronavirus.
On May 4, 2022, the healthy life news network of the United States reported that the University of Michigan found that the probability of airborne transmission of novel coronavirus was 1000 times that of contact with the surface of objects. Researchers at the University of Michigan tested air and surface samples on university campuses and found that the probability of inhaling virus particles was greater than the probability of finger contact infection.
