What is the matter that the nucleic acid test of the new crown infected person shows positive multiple times?
The new crown exists like an "unkillable bug", and the infected people also have multiple positive nucleic acid tests. Such infected people are called "Changyang patients." According to a report by the European Network of Italy citing EUNEX news agency, an Italian patient with new crown pneumonia said through social media that he has been isolated at home since he was diagnosed in April 2020. During this period, he had undergone 15 virus tests and each time was positive. The patient is currently in good physical condition, but he almost collapsed due to prolonged isolation. After the patient released the news, it attracted great attention from all walks of life and Italian health authorities.
Nucleic acid detection material-Virus Transporattion Medium
In fact, this kind of "Changyang patients" has also existed in my country. At the State Council's joint prevention and control mechanism press conference on April 25, the Health Commission revealed the number of "Changyang patients" in Hubei for the first time. Jiao Yahui, Inspector of the Medical Administration and Hospital Administration of the National Health Commission, said: "More than 30 people have not turned negative for a long period of time, but they no longer need treatment." At present, all patients in Wuhan Changyang have been cleared. Zhang Luliang from Wuhan Pulmonary Hospital told a reporter from the Health Times: "On June 4, the national expert group evaluated and confirmed that the last three patients with new coronary pneumonia in Wuhan reached the discharge standards. On June 15, all asymptomatic infections in Wuhan were also cleared. zero."
Question: What is a "Changyang patient"?
Answer: The concept of "Changyang patients" refers to patients who meet the discharge criteria (no respiratory symptoms, obvious absorption on CT images), but the nucleic acid test continues to be positive for a long time. Zhang Boli, an academician of the Chinese Academy of Engineering, said that after cultivating and sequencing the virus in patients, it was found that the virus in some patients was "dead virus", that is, after the virus died, "corpse" fragments remained in the human body to form gene fragments. This may be Nucleic acid testing is the cause of Changyang.
Question: Is there a lot of "Changyang patients" in my country?
Answer: “In general, there are not many such patients. Among the 1,268 patients with new coronary pneumonia admitted to Zhejiang Province, we only encountered one.” Professor Sheng Jifang, Director of the Infectious Diseases Department of the First Hospital of Zhejiang University, said in an interview with the Health Times. A patient in his 60s was diagnosed in the acute stage and lasted for 45 days to turn negative. After turning negative, we continued to give him a week of consolidation treatment. He has recovered and is discharged from the hospital, and his condition is relatively good."
Q: Does Changyang patient need treatment if he has no symptoms?
Answer: Liang Zongan, director of the Department of Respiratory and Critical Care Medicine, West China Hospital of Sichuan University, once introduced it at a press conference on the Joint Prevention and Control Mechanism of the State Council. Because the vast majority of "Changyang" patients are asymptomatic, if there are no other underlying diseases, this condition does not require treatment, but because the nucleic acid test is still positive, necessary isolation and observation are still required. Without the condition, it is no different from a normal person, but has been isolated in the hospital, making it unacceptable for many patients. "Always occupying limited medical resources is not a solution." Zhang Yafei, a secondary investigator of the Shenzhen Municipal Health and Health Commission, said in an interview with the Health Times that these patients can be arranged in hotels and other isolation points for isolation and observation, and there is no need to stay in hospital.
Q: Are Changyang patients infectious?
Answer: "Whether Changyang patients are infectious depends on the virus in the body. If the PCR nucleic acid test has been carried out for 30 cycles and the CT value is above 30, then the infectivity is relatively weak; if it is just a viral gene fragment, it means that it may be dead. Viruses are not contagious anymore." Professor Sheng Jifang said. Moreover, in the discharge standards of the "New Coronavirus Pneumonia Diagnosis and Treatment Plan (Trial Seventh Edition)", it is required to collect two consecutive sputum, nasopharyngeal swabs and other respiratory tract samples for nucleic acid testing, and the test is negative before discharge. As long as the nucleic acid is positive for Changyang patients, no matter how good the other conditions are, they have to stay in the hospital for continued observation. So the public need not worry about being infected by Changyang people.
Nucleic acid testing is an important means of epidemic prevention and control
Nucleic acid detection is currently an efficient and convenient method for detecting the diagnosis of new coronaviruses, but its detection rate cannot reach 100%. Now, nucleic acid detection and antibody detection are combined to improve the accuracy of detection results. Before the vaccine is successfully developed, nucleic acid testing is still an important means of epidemic prevention and control.
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