Hubei Provincial Health Commission announced on February 20: 19, the province’s new confirmed cases of 349 cases, of which 615 new confirmed cases in Wuhan. Wuhan from February 2 to 18, 17 consecutive days of new confirmed cases of more than a thousand people, February 19 this number finally “fell back” three digits. Why is the number of new confirmed cases in the province smaller than in Wuhan, and how is this figure calculated? Why is the number of confirmed cases so calculated? It is understood that this is related to the National Health Commission on February 19th released the “new coronavirus pneumonia diagnosis and treatment program (trial sixth edition)” for the “diagnostic criteria” changes. In the sixth edition, the “diagnostic criteria” eliminates the distinction between Hubei Province and other provinces outside Hubei Province, and is unified into two categories: “suspected cases” and “confirmed cases” (see figure below). The fifth edition of the Hubei Province Diagnostic Criteria is divided into three categories: “suspected cases”, “clinically diagnosed cases” and “confirmed cases”. The “clinical diagnosis cases” are divided into three categories, of which the description of “clinical diagnosis cases” is “suspected cases with imaging features of pneumonia”. It can be seen that according to the sixth edition, which is the latest “diagnostic and treatment criteria”, confirmed cases must meet at least one of the following pathogenetic evidence: Positive nucleic acid test, highly homologous gene sequencing, and the previous “clinical diagnosis cases” in the fifth edition of the “diagnostic and treatment criteria”, which is the most recent version of the “diagnostic and treatment criteria”. “Clinically diagnosed cases” are no longer classified as confirmed cases because they do not meet the criteria of a positive nucleic acid test. What do you think about the elimination of CT as a clinical diagnostic criterion? In the 6th edition of the new diagnosis and treatment program for Crown pneumonia, CT is no longer used as a clinical diagnostic criterion, are we back to square one? In response to this question, in fact, as early as February 13th interview with reporters, Wuhan University Zhongnan Hospital imaging professor Zhang Xiaochun had made a prediction. Zhang Xiaochun introduction, nucleic acid is the genetic material of the organism, influenza A and influenza B viral nucleic acid is different, the new coronary pneumonia and sars viral nucleic acid is also different, nucleic acid test can be clear patients in the end is infected by which kind of virus microorganisms, this diagnosis is very rigorous. In comparison, CT is an indirect evidence, which is mostly used as an aid to diagnosis. If so, why did Zhang Xiaochun call for CT to be used as a clinical diagnostic standard on February 3? Zhang Xiaochun explained that this is because the detection rate of nucleic acid testing is only about 40%, and there is a possibility of missed diagnosis. First of all, the reagent itself is developed in a short period of time, and it is impossible to pursue perfection in a hurry; secondly, the doctors supporting the fever clinic come from various departments, and not everyone can skillfully master the technique of pharyngeal swab sampling; in addition, unlike upper respiratory tract infections such as influenza, neocoronaryngitis occurs in the lower respiratory tract, and the patient has a dry cough without sputum as the main manifestation. Without sputum, it is difficult to collect a valid sample from a throat swab. The reality in early February was that the stock of suspected cases was too large in Hubei Province, which was the hardest hit area of the outbreak. A large number of suspected patients could not be diagnosed due to negative nucleic acid and could not be centrally admitted, which was very unfavorable to the prevention and control of the epidemic. Therefore, take CT as a clinical diagnostic standard is a special period of special means, only applicable here and now, another time, another scene, may not be applicable. Zhang Xiaochun said, from the data since the 12th, the epidemic in Hubei Province in a large scale has been controlled, at this time the diagnosis and treatment program to make adjustments is not unexpected. “I don’t think it’s back to square one; on the contrary, I think our measures have achieved good results.” Source: Global Times