Beijing News (Reporter Dai Xuan Xu Wen) On April 25, severe cases in Wuhan were cleared. According to Jiao Yahui, Supervisory Commissioner of the Medical and Medical Administration of the National Health and Health Commission, the number of confirmed cases in Wuhan has been reduced to 47, of which more than 30 have long-term nucleic acids that are not negative and are Changyang patients. Changyang patients only have nucleic acids that never turn negative, but no treatment is needed.
What is a "changyang patient"? Why does it not need treatment? Is it contagious? Experts believe that this part of the patients accounted for a small proportion, no clinical symptoms, no treatment, theoretically still infectious. Whether it can eventually turn negative and whether it is possible to carry the virus for a long time still needs further study.
Interpretation 1: What are the characteristics of "Changyang patients"?
"Changyang patients refer to the discharge criteria. If there is no respiratory symptoms, after CT images are clearly absorbed, the positive time will last longer." Tong Zhaohui, an expert in the central guidance group and an expert in respiratory infections and critical illness, said he was warded in Wuhan I have also been in contact with Changyang patients during this period, and admitted that the existence of Changyang patients is normal.
Yuan Xiaodong, deputy chief physician of the Department of Infectious Diseases, Beijing Shijitan Hospital, is a member of the Beijing-Egeria Medical Team, and has been supporting a new coronary pneumonia designated hospital in Wuhan for more than two months. In the wards where he works, there are also cases where the nucleic acid cannot turn negative for a long time.
"One of the patients was not seriously ill when he was admitted to the hospital, with a slight cough and a little abnormal CT. In about twenty days, the respiratory symptoms disappeared and the CT was completely absorbed, but the nucleic acid turned negative after waiting for more than 40 days in the ward . There is another person whose symptoms are very mild, but it turns cloudy in about a month. "Yuan Xiaodong said.
Li Haichao, the team leader and deputy director of the National Aid Medical Team of Peking University First Hospital, also encountered patients from Changyang during his aid to Hubei. He introduced that the patient's pneumonia has actually improved significantly, the symptoms have basically disappeared, and the absorption of lung shadows is also ideal, but the nucleic acid test has been slow to turn cloudy and he has been unable to leave the hospital.
Li Haichao said that when the medical team left, two such patients in the ward were handed over to the local hospital. The nucleic acid positivity of these two patients lasted quite a long time, from the onset to the test before they left for about a month or even longer. "It's not just our ward, there are patients like this in the wards of the Brothers Hospital, so after the National Medical Team evacuated, this part of the patients were transferred to the local hospital for special treatment."
Interpretation 2: Why is there a "Changyang patient"?
Tong Zhaohui introduced that the current situation of Changyang is still being studied and observed. Previous studies on other viruses have found that older patients with more underlying diseases and hormone use have a longer conversion time.
Yuan Xiaodong analyzed that the duration of turning negative was related to the patient's autoimmune response. "New Coronary Pneumonia and SARS are diseases caused by coronavirus, and there are some similarities between the two. For example, they both have an acute progression around the second week. The pathogenesis of SARS is mainly due to the damage of the immune response to the human body. The new crown also exists. "
Yuan Xiaodong explained that when the patient's immune response is intense, on the one hand, it is easy to kill the virus quickly, and it may also harm itself. In clinical practice, some critically ill patients have a shorter nucleic acid negative time, while some mildly ill patients are not particularly aggressive, and the negative time is longer, which may be a delicate balance between human immunity and viruses.
"It can also be analyzed in conjunction with immune responses to other diseases, such as hepatitis B. The younger children are less immunized against hepatitis B, have no symptoms, and easily coexist with the virus to form a chronic hepatitis B infection. 90% of adults can clear the hepatitis B virus after infection. Hepatitis symptoms appear in this process. Among the children with new coronary pneumonia, there are fewer serious illnesses, which may be due to the immature immune system of the child and the immune response is not too intense. "Yuan Xiaodong said.
Interpretation 3: Is "Changyang Patient" contagious?
Yuan Xiaodong introduced that whether it is infectious depends on whether there is live virus in the patient. If there is, then the theory is still infectious, but the symptoms are not obvious, the general infectivity is weaker; if it is only dead virus, it will be in It metabolizes naturally within a period of time and is not contagious. "How long will this positivity last? There is no standard for the new crown. With reference to the influenza virus, it will generally not be overcast for more than a week."
Tong Zhaohui introduced that there are domestic disease control agencies that have carried out virus cultivation for such patients, and the research is continuing. The current results are all negative, which means that it may be a dead virus or a viral gene fragment. Observing their close contacts, there is no disease or nucleic acid positive.
"Some of the patients with 'Fuyang' appeared before, and there may be a coincidence with the Changyang patients now said. This group of patients is likely to have a false negative nucleic acid test at the time of discharge. In fact, they have always been positive." He also said.
Li Haichao also said that Changyang patients are theoretically contagious. As long as patients have live virus that can be excreted from the body, in principle they are contagious, but the strength of the infection depends on the amount of virus excreted. "This part of the patient needs close follow-up, and the patient's new coronavirus load should be tested to see what specific amount of virus he carries, which is of reference value for evaluating infectivity. Generally, the less viral load , The less contagious. "
Interpretation 4: Why does "Changyang patients" not need treatment?
Li Haichao said that if you don't look at the nucleic acid test results, the two "Changyang patients" seem to be patients in the rehabilitation period, and they are recovering relatively well. There is no need to take any treatment measures for this part of patients, only isolation is needed to prevent further infection.
As for whether the condition will be repeated, Li Haichao said that it is unlikely that the symptoms will appear again. If the "Changyang patient" is cured after the disease, and there are antibodies in the body, in the current epidemic cycle, although the virus has been detected, mutations have The viral antigenicity of the data is not very large, so the antibodies produced by the patient are protective, so that the patient's chance of reinfection basically does not exist.
Interpretation 5: Is it possible for "Changyang patients" to turn negative?
Li Haichao explained that in some patients with new coronary pneumonia, the nucleic acid will turn negative quickly, and some patients will take longer to turn negative, which should be followed regularly in the crowd. According to the diagnosis and treatment plan of the National Health Commission, the discharge standard must be two consecutive negative nucleic acids. If the nucleic acid is positive, even if other conditions are better, you must stay in the hospital to continue observation. On the contrary, there are patients with very serious conditions, such as lung lesions that are seriously damaged, and the nucleic acid turns negative early.
"Although we don't quite understand the scale at this time, what is certain is that the proportion of 'Changyang patients' is very low, but the specific proportion is unclear." Li Haichao said.
Li Haichao said that there are also carriers of hepatitis B and AIDS, but its transmission route is special. Generally speaking, respiratory viruses are less likely to be chronic viral infections. "Changyang patients" do not yet know how long it will turn cloudy. In fact, I think of these 30 cases of "Changyang patients", there will be some people who turn cloudy after a while. If it is really long Time virus nucleic acid is positive, this is a very important subject and needs to be studied.
Interpretation 6: If you are positive for a long time, how to return to normal life?
Li Haichao said that this will face a new challenge. Patients must be eager to return to normal life, but they are also a detox person and may be contagious. In my opinion, this part of the patients needs to be further closely observed, and the virus discharge, that is, viral load, should be regularly monitored, and then comprehensively analyzed. If the patient discharges a lot of virus, it may be necessary to consider a special public health policy for this part of the patient.
Beijing News reporter Dai Xuan Xu Wen