Xu Jianguo, the leader of the assessment expert group and an academician of the Chinese Academy of Engineering, explained the "new coronavirus"
Qu Ting / Xinhua News Agency
Question 1: At present, what progress has been made in the pathogenic identification of unexplained viral pneumonia in Wuhan?
Xu Jianguo: As of 21:00 on January 7, 2020, a new coronavirus was detected in the laboratory, and the entire genome sequence of the virus was obtained. A total of 15 positive results of the new coronavirus were detected by nucleic acid detection methods. From 1 positive patient The virus was isolated from the samples and showed a typical coronavirus appearance under an electron microscope.
The expert group believes that the pathogen of this unexplained case of viral pneumonia was initially identified as a new type of coronavirus.
Question 2: How is the pathogen identification carried out?
Xu Jianguo: The tissue laboratory used genomic sequencing, nucleic acid detection, virus isolation and other methods to perform pathogenic tests on patients' alveolar lavage fluid, throat swabs, blood and other samples.
Question 3: What procedures are needed to identify the pathogen?
Xu Jianguo: To confirm the cause of an epidemic disease, usually the following points must be met: (1) Suspicious pathogens must be found in patients, and pathogenic nucleic acids can be detected in clinical samples of patients; (2) From clinical samples of patients The pathogen can be successfully isolated; (3) The isolated pathogen can cause the same disease symptoms after infecting the host animal. The patient's serum antibody titer during the recovery period increased four-fold, which can help identify the pathogen.
Finding the nucleic acid, genomic and antibody evidence of the pathogen from the patient can be done in a short time. Scientific research, such as pathogen isolation and pathogenicity identification, can take weeks. The development of specific drugs and vaccines against a new pathogen may take years to complete.
Question 4: What is the next step?
Xu Jianguo: The expert group believes that the pathogen of this unexplained case of viral pneumonia is initially determined as a new type of coronavirus. The next step is to conduct expert research and judgement in combination with etiology research, epidemiological investigation and clinical manifestations.
Question 5: What is a coronavirus?
Xu Jianguo: Coronavirus is a type of pathogen that mainly causes respiratory and intestinal diseases. There are many regularly arranged protrusions on the surface of this type of virus particle, and the entire virus particle is like an emperor's crown, hence the name "coronavirus". In addition to humans, coronaviruses can infect many mammals such as pigs, cattle, cats, dogs, marten, camels, bats, mice, hedgehogs, and various birds. So far, there are six known human coronaviruses. Four of these coronaviruses are more common in the population and are less pathogenic, generally causing only minor respiratory symptoms similar to the common cold. The other two coronaviruses—Severe Acute Respiratory Syndrome Coronavirus and Middle East Respiratory Syndrome Coronavirus, also known as SARS Coronavirus and MERS Coronavirus, can cause severe respiratory diseases. The new coronavirus that caused the epidemic is different from the human coronaviruses that have been discovered, and further understanding of the virus requires further scientific research.
(Originally entitled "Experts make preliminary progress in the identification of the pathogen of a new coronavirus in Wuhan with unknown cause of viral pneumonia")