{"id":7199,"date":"2020-04-08T14:13:11","date_gmt":"2020-04-08T06:13:11","guid":{"rendered":"http:\/\/www.whatchina.cn\/?p=7199"},"modified":"2020-04-08T14:13:11","modified_gmt":"2020-04-08T06:13:11","slug":"looking-through-the-covid-19-virus-detection-these-key-issues-cannot-be-ignored","status":"publish","type":"post","link":"https:\/\/www.whatchina.cn\/looking-through-the-covid-19-virus-detection-these-key-issues-cannot-be-ignored.html","title":{"rendered":"Looking Through The Covid-19 Virus Detection, These Key Issues Cannot Be Ignored"},"content":{"rendered":"<div class=\"37c28470d9d6d3cb9ff74e663adb766a\" data-index=\"2\" style=\"float: none; margin:0px 0 0px 0; text-align:center;\">\n<script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-3594734025006597\"\r\n     crossorigin=\"anonymous\"><\/script>\n<\/div>\n<p>The detection reagents that have been developed are actually divided into three categories, namely nucleic acid, antibody and antigen detection.<br \/>\nSince the full gene sequence of the COVID-19 virus was released on January 11, 2020, various virus detection methods and equipment have rapidly developed. At present, there seem to be many detection reagents available on the market, some of which are simple detection methods aimed at the public.<br \/>\nHowever, the reporter learned in the interview that the detection reagents that have been developed are actually divided into three categories, namely nucleic acid, antibody and antigen detection, and what is the difference between them? What about accuracy? How do people in the industry view different detection methods?<br \/>\nIt is understood that there are usually two strategies for detecting infectious diseases, one is to detect the pathogen itself, and the other is to detect the antibodies produced by the human body in order to resist the pathogen. Pathogen detection can detect antigens as well as nucleic acids. Antibodies are a type of protein product produced by the human immune system against viruses, and are usually produced 1-2 weeks after infection. Therefore, if any one of nucleic acid, antibody or antigen is detected in the subject&#8217;s body fluid, it means being infected.<br \/>\nChen Jingxian, an expert in the subject of Golden Respiratory Diseases and an inspection team of the Golden Coronary Medicine New Coronavirus Pneumonia Epidemic Prevention and Control Group, said in an interview with the First Financial Reporter: &#8220;Viral nucleic acid is a component of a virus, so detection of nucleic acid means There are pathogens. It can be used for early diagnosis, as well as for the observation of the treatment effect during the course of disease and as an indicator of treatment discharge. The specificity and sensitivity of detecting nucleic acids are extremely high, because viral nucleic acids can be used in the laboratory for a short time. Internally selectively amplified by several million times and easily detected. &#8221;<br \/>\nThis is why nucleic acid detection is still considered the &#8220;gold standard&#8221; for COVID-19 virus detection. Chen Jingxian further said: &#8220;Because the COVID-19 virus is a new virus, we have no pre-existing antibodies to it, so when an antibody (either IgM or IgG) appears, it means that it has been infected. The antibody is positive. It can be a patient, but it can also be an asymptomatic infected person, a recessive infected person, or a convalescent patient and a vaccine recipient. &#8221;<br \/>\nHe pointed out to reporters that although antibody detection is simple and fast at the technical level, its specificity and sensitivity are usually lower than nucleic acid detection. This is because it is not easy to prepare a highly specific antigen. For example, the antigen used to detect the COVID-19 virus must not only cross-react with other bacteria and viruses common in the respiratory tract, but also be able to be related to other coronaviruses, especially relatives. The closely related SARS coronavirus, SARS-like bat coronavirus, etc. can be distinguished.<br \/>\nThe reporter also noticed that after the human body was infected with COVID-19, there was a difference in the time that nucleic acids and antibodies could be detected. According to theoretical data, nucleic acids can be detected 1-2 days after infection; IgM (antibody) can be detected in about 7-14 days; IgG (antibody) can be detected in about 21 days. And some patients with weak immune function may have a phenomenon of low antibody amount, which is easy to cause false negative problems in antibody detection. At the beginning of infection, the pathogen antigen content is also low, which is also not easy to detect. Therefore, antibody testing should not be used as a basis for eliminating infection.<br \/>\nWith the continuous development of the epidemic situation, companies are scrambling in the field of detection, and the public&#8217;s expectations for virus detection are also increasing. Should we correctly see the COVID-19 virus detection?<br \/>\nAccording to reporters, the current COVID-19 virus-related detection products are professional medical device products. Although the colloidal gold method is simple to operate and only requires blood collection testing, the purpose approved by the state also clearly stipulates that it can only be used by medical institutions. Professional medical professionals. The reason is that the collection of blood samples requires certain conditions, the test requires corresponding temperature and humidity, and the judgment of the results requires corresponding professional knowledge (especially in a critical state). There are certain risks in self-operation, and AIDS, hepatitis B, etc. will also be transmitted through the blood.<br \/>\nIn addition, although some social platforms such as WeChat Moments and other social platforms have been selling self-test equipment, but the relevant regulations are clear, new coronavirus detection kits are managed according to the third category of medical devices, and must be sold by qualified and licensed companies , And these enterprises can not be sold to individuals, because the purpose approved by the state clearly stipulates that it can only be used by medical institutions.<br \/>\nAttachment 1: The characteristics of the different detection methods that have been approved (of which only the colloidal gold method does not need to be operated in the laboratory)<br \/>\n1. Fluorescence PCR method: The detection of specific target genes of COVID-19 virus is usually completed in 2-3 hours; however, it needs professional personnel to operate in the laboratory, and cold chain is required for transportation.<br \/>\n2. Combined probe-anchored polymer sequencing method: whole genome sequence determination, the accuracy rate can reach 100%, but the cost is high, the operation is complicated, and it is not suitable for routine clinical detection. Usually 22 hours.<br \/>\n3. Colloidal gold method: Similar to blood glucose meter test paper, the operation is simple, the results can be interpreted with the naked eye within 15 minutes, and the auxiliary diagnosis of early infection and past infection can be carried out without the need for testing equipment, which is suitable for large-scale rapid screening. The operation is simple, but the sensitivity is low. The colloidal gold detection reagent is used for the qualitative detection of novel coronavirus (2019-nCoV) IgM \/ IgG antibodies in human serum, plasma and whole blood samples in vitro.<br \/>\n4. Constant temperature amplification chip method: can simultaneously detect COVID-19 virus, influenza A virus, H1N1 influenza virus, influenza A H3N2 virus, influenza B virus, and respiratory syncytial virus. Generally 1.5 hours. However, some rare pathogenic pathogens may be missed.<br \/>\n5. Magnetic particle chemiluminescence method: high sensitivity, high specificity, good repeatability, and high degree of fully automatic. However, special chemiluminescence detection equipment is required, which can detect 200 batches in batches, and the results are usually produced in 30 minutes.<br \/>\n6. Constant temperature amplification-real-time fluorescence method: detect the specific target gene of COVID-19 virus, and amplify at the same temperature. Compared with the fluorescent PCR method, the equipment requirements are lower, and it is usually completed within 1-2 hours.<br \/>\n7. Hybrid capture immunofluorescence method: detect the specific target gene of COVID-19 virus, the size of the supporting detection equipment is small, and the detection time of a single sample is shorter, generally about 1 hour.<br \/>\n8. RNA capture probe method: detect the specific target gene of COVID-19 virus, effectively reduce pollution, simple operation, continuous detection, usually about 1.5 hours to complete.<\/p>\n<div class=\"37c28470d9d6d3cb9ff74e663adb766a\" data-index=\"2\" style=\"float: none; margin:0px 0 0px 0; text-align:center;\">\n<script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-3594734025006597\"\r\n     crossorigin=\"anonymous\"><\/script>\n<\/div>\n\n<div style=\"font-size: 0px; height: 0px; line-height: 0px; margin: 0; padding: 0; clear: both;\"><\/div>","protected":false},"excerpt":{"rendered":"<p>The detection reagents that have been developed are actually divided into three categories, namely nucleic&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[272],"tags":[],"class_list":["post-7199","post","type-post","status-publish","format-standard","hentry","category-today"],"_links":{"self":[{"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/posts\/7199","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/comments?post=7199"}],"version-history":[{"count":0,"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/posts\/7199\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/media?parent=7199"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/categories?post=7199"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/tags?post=7199"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}