This week, the Diagnosis and Treatment Plan for Novel Coronavirus Pneumonia (Trial Ninth Edition) was released. Compared with the eighth edition, the ninth edition of the diagnosis and treatment protocol optimizes the case detection and reporting procedures, supplemented by antigen detection, and further improves the ability to detect cases early. In the new version of the diagnosis and treatment plan, a change in the value has aroused heated discussion, that is, the Ct value standard has been reduced from 40 to 35. So what is the Ct value and what does this adjustment mean?
Li Tongzeng, chief physician of the Department of Respiratory and Infectious Diseases of Beijing You'an Hospital: We used such a machine, called nucleic acid amplification, which is how many times I enlarged, and then I found and confirmed the genetic material of this virus. If we need to cycle 30 times, simply we need to magnify this thing 30 times to see, we find a high Ct value, then it means that his viral volume is low, which is an inverse ratio. He may be in recovery or early in the (infection) stages.
If it is tested for the first time, the Ct value is obtained, and it has not been treated, it is relative whether the Chinese and foreign judgments are positive or negative.
Li Tongzeng, chief physician of the Department of Respiratory and Infectious Diseases of Beijing You'an Hospital: There are already many areas abroad, so I put the limit on (Ct value) 35, that is, (Ct value) above 35, I will report negative, or the report is not detected. Some places abroad even put this wider, (Ct value) above 30 can be considered that it is not contagious. It doesn't seek to find all the infected people, it is more concerned with finding these severe cases and determining which people need to be hospitalized. We want to maintain a dynamic clearance, when we find an infected person, such as (Ct value) between 35 and 40, we will also consider that he is positive, we will go to him to do the flow adjustment, try to find all the infected people, so as to avoid the spread of the epidemic.
Internationally, ct values exceeding 35 are generally judged to be negative, and mainland China requires ct values over 40 to be judged negative, so as to trace the source to find as many infected people as possible. The new version of the protocol reduces the Ct value from 40 to 35, which emphasizes the criteria for the release of isolation and discharge from mild disease after a period of treatment. The summary of clinical experience behind this decision covers almost two years from the beginning of the epidemic to the present.
Li Tongzeng, chief physician of the Department of Respiratory and Infectious Diseases of Beijing You'an Hospital: At the earliest time of the epidemic, some fuyang cases were found, and I felt that we needed to let him stay longer, and whether to take some stricter (out-of-hospital isolation) management measures. We have been monitoring these people in Fuyang for the past two years, and we found that there is no live virus, and he has not transmitted it to the people around him. We think that if he has a Ct value of more than 35, even if he returns to yang, then he is not contagious. From (Ct value) 35 to 40, its time is relatively slow, unlike the previous rapid decline in viral load, from (Ct value) 40 to 35, may be on average, will shorten the length of hospital stay of four or five days.
Experts introduced that the Ct value 35 standard is still the most stringent in the world, although it is not contagious, but it still needs to be monitored. The plan was revised, and the time for isolation management and health monitoring after discharge was reduced from the past 14 days to 7 days of home monitoring.
Li Tongzeng, chief physician of the Department of Respiratory and Infectious Diseases of Beijing You'an Hospital: There is a difference in wording here, it used to be home isolation, and it is now (called) health monitoring. You just need to wear a mask, wash your hands frequently, pay attention to these, and try to keep a distance from your family and those around you, which is a basic requirement. For whether it is necessary to go out, we look at this plan, and there is no strict limit.
The modification of ct value standard is conducive to the rational allocation of medical resources
It can be seen that the adjustment of the Ct value standard does not mean that the positive value of the nucleic acid test has changed, it emphasizes that after a period of treatment, the isolation and discharge criteria are lifted. The new version of the diagnosis and treatment plan proposes to classify and treat cases. Among them, it is clear that mild cases are subject to centralized isolation management. The adjustment of the Ct value standard is of great significance to the rational allocation of medical resources.
Li Tongzeng, chief physician of the Department of Respiratory and Infectious Diseases of Beijing You'an Hospital: In the early days, the proportion of mild diseases is relatively small, I don't know which one will develop into severe disease, which he may be fine after 5 to 7 days, so in the early days we adopted all the treatment to the designated hospital. Then after the appearance of Omicron, 90% of them are mild. If this plan is not modified, one designated hospital is not enough, and even more designated hospitals are admitted for treatment, it may be that a building is to be vacated, or even the entire hospital is to be vacated. Recently, the news has also seen that outpatient clinics have been closed in some places, and in some places, emergency departments have been suspended. Such an adjustment not only reduces the burden on our infected people themselves, but more importantly, it also reduces the burden on medical institutions and medical staff.
Experts emphasize that the modification of Ct values and the classification of treatment prevent the run on medical resources and avoid affecting the treatment of other new crown patients and routine patients.
Li Tongzeng, chief physician of the Department of Respiratory and Infectious Diseases of Beijing You'an Hospital: The current epidemic is Omicron, many places are Omi kerong BA.2, it is the most contagious, and the immune escape ability is the strongest, and the measures taken are faster, including our launch of antigen testing, that is, we want to find some infected people earlier, which is the so-called tight. The Omiljung mutant strain is less virulent, more people do not need to be hospitalized, especially the release of isolation and the relaxation of discharge criteria, which is reflected in the looseness. Whether it is tight or loose, there is a scientific basis. In 2020, in fact, eight versions (diagnosis and treatment plan) have been intensively introduced, from the eighth edition in 2020 to the eighth revision in April 2021, with an interval of half a year in between, and this time (with the eighth revision) an interval of 11 months, which is actually based on the characteristics of the virus in this time. Therefore, we say that this version of the diagnosis and treatment plan is more reasonable, more scientific and more accurate. Many countries currently report that the case fatality rate of infected people in Omi kerong is significantly lower than that of influenza, but this is conditional, one is that the countries and regions that have been vaccinated can be like this, and many of these countries have a large number of infected people in the early stage, and many people have died of illness and are immunized through natural infection. The reason why we are not yet fully liberalized is that our vaccination rate, especially the elderly, have not been vaccinated for various reasons, and we cannot completely eliminate these prevention and control measures as in foreign countries. The main thing is that we have to make time for those who have not yet been vaccinated to complete the vaccination.
Source: CCTV News