Original title: Chinese test reagents bought in the Czech Republic, the error rate is as high as 80%? !!
A health expert from the Moravian-Silesian region of the Czech Republic said in an interview recently that the error rate of Chinese testing reagents bought in the Czech Republic reached 80%.
In response to this problem, Roman Prymula, Czech Deputy Minister of Health, came forward to clarify on the 23rd that the statement of 80% error rate is incorrect. There is indeed a 20% -30% error rate for China’s rapid test reagents. The Czechs already knew about this. The reason why the Czech Republic has an error rate of 80% is that the local medical institutions in the country have misunderstandings about the use of rapid testing reagents and used them incorrectly.
Comprehensive “Corniche Prague”, Novinky News Network and other Czech media reported on the 23rd that the rapid detection reagent detected the antibody to the new crown virus in the human body, and a few days before the infection of the patient, there may be the presence of the crown virus in the body, and the antibody is still present. It is not generated and therefore cannot be detected. Therefore, rapid antibody detection can only play a “assistance role” in the test, and cannot be used as a diagnostic test.
Primila said that the Czech Republic’s initial recommendation to medical institutions was to test people with symptoms of infection that lasted for 3 days, and he suggested that the use of the rapid test reagent be postponed to the 5th day.
He said: “The rapid test does not lead to a real conclusion. If the test result is negative, it means that the person being tested does not have antibodies. If he does not have antibodies, it means that he is healthy, or no virus has been found.”
For the current use in China Feng Luzhao, a researcher from the China Centers for Disease Control and Prevention, made a related presentation at the press conference of the Joint Prevention and Control Mechanism of the State Council on March 20: The currently approved new crown pneumonia detection reagents include two types, one is a nucleic acid detection reagent. One is the antibody detection reagent.
The nucleic acid detection process includes multiple steps such as specimen processing, nucleic acid extraction, and PCR detection. The average detection time takes 2-3 hours. Because it directly detects viral nucleic acids in collected specimens, it has strong specificity and relatively high sensitivity, which is the main detection method at present.
Antibody detection includes colloidal gold method and magnetic particle chemiluminescence method. The average detection time of colloidal gold method is about 15 minutes. A drop of blood can be observed with the naked eye within 15 minutes. The magnetic particle chemiluminescence method generally requires 30-60 minute.
Antibody testing can be used to assist in the diagnosis of cases with negative nucleic acid tests, and to screen and screen cases, but it is not a substitute for nucleic acid detection methods. This is because antibody detection measures the level of antibodies in human blood. In the early stages of infection of the disease, antibodies may not be produced in the body, so it has a window of detection.