A large number of cases after multiple tests to test positive, the virus become cunning?

15, 31 provinces added 115 new confirmed cases of local corona pneumonia, including 90 reported in Hebei Province, new confirmed cases in the region have broken 100 for four consecutive days.
, the number of confirmed cases in Hebei Province is still climbing, and several rounds of full nucleic acid testing have been carried out in some parts of the province.
the details of the confirmed cases released by Hebei authorities recently, the reporter noted that there are a large number of cases that have been tested positive for nucleic acid.
many netizens wonder: is the nucleic acid not good, or the virus cunning?the outbreak of neo-coronary pneumonia, nucleic acid detection has become a near-household word.
nucleic acid testing is mainly to detect nasopharyngeal swabs, pharynx swabs, sputum and other specimens whether there is a new coronavirus nucleic acid, the positive test results indicate infection with the new coronavirus. From a professional point of view, screening for new coronavirus infections through nucleic acid testing is considered to be the most important means and measures to achieve "early detection" and "early diagnosis".
, however, recent news reports about the outbreak have been "confirmed cases of nucleic acids are negative many times" news is not uncommon.
For example, the reporter combed found that january 14 at 0-24 hours, Shijiazhuang new 84 new cases of new crown pneumonia confirmed cases, there are 56 cases of nucleic acid testing had been negative, and then turned positive cases.
of these, "confirmed cases 51" were negative on 3, 5, 7, 9, 11 and 12 nucleic acid tests;
"Confirmed Case 12" tested negative for five nucleic acid tests on 3, 4, 6, 9 and 11 January, but it collected pharynx swabs on 12 January and tested positive for nucleic acid on 13 January, and was diagnosed as a confirmed case on 14 January.
similar, on January 14th, from 0-24, two of the six new confirmed cases in Yantai were negative for nucleic acid testing.
, "confirmed case 6" on the 4th, 5th, 7th, 10th 4 nucleic acid test results are negative. On the 14th, the nucleic acid tested positive.
Of the 83 new confirmed cases of neo-crown pneumonia in Shijiazhuang City at 0-24 p.m. on January 15, only 14 cases tested positive for nucleic acid at one time, and the rest were confirmed after multiple nucleic acid tests;fact, the phenomenon of testing positive for nucleic acid after many nucleic acids does not occur only in Hebei. A similar situation has been repeated before.
a few days ago, "Shijiazhuang someone nucleic acid test 6 times before testing positive" has been on the Internet hot search list.
In Liaoning, January 4, Dalian City, the outbreak prevention and control press conference, Dalian Civil Affairs Bureau Director Tang Yi also mentioned, "Some cases have done 11 nucleic acid tests to show positive, some areas tested 6 rounds and positive cases appear." "
, what affects the results of nucleic acid testing?"
is now clear that nucleic acid testing is certainly not 100%. Wang Guangfa, director of Peking University's First Hospital, told Xinhua in an interview that similar situations had previously appeared in many places, including Wuhan.
factors affecting testing, including the following: the patient's detox concentration, the quality of the test samples, the quality of the kit, and laboratory operations.
Wang Guangfa believes that, in theory, among many factors, the test results are mainly affected by the detox concentration of patients. "Patients can find out a lot more detox, they can't find it if they detox."
, Shijiazhuang CDC microbiological testing director Gao Weili in an interview with the media also talked about this phenomenon.
he explained that there are many reasons for this phenomenon, the most important is the amount of detoxifying respiratory secretions. The high probability is that the patient's amount of detox in the respiratory tract is very small, so it is not easy to detect., then, what causes patients to detox less?
Wang Guangfa told reporters that this is related to the progression of the disease. After many nucleic acid tests to test positive, the high probability is due to different patients detox time caused.
" just after the nucleic acid, it is very likely to be negative. He said, "What we have now is basic the last two days of the incubation period to test positive." The incubation period is different for each patient, so the time to detect the virus is different. Feng zijian
deputy director of the China Center for Disease Control and Prevention, also spoke about the phenomenon in an interview earlier.
He explains that an infected person or patient begins detoxifying from exposure to a virus, professionally known as a "strong recession period", while a detox professional for asymptomatic infected persons is called a "pre-recession period", which can also be called a window period for laboratory test screening. During the window period, testing many times may not test positive, but by the end of the pre-hidden period will test positive, this phenomenon is perfectly understandable.
Cao Qi, deputy director of infection medicine at Beijing Concord Hospital, pointed out that current studies have confirmed that the most active time for the new coronavirus to replicate and excrete from the pharynx is before and after the oncology of clinical symptoms, at which point the pharynx nucleic acid test is the most likely to test positive. "But it's not that wide."
according to the above statement, if the nucleic acid test, the patient just detox, the test results may be negative. Therefore, repeated multi-round testing is even more necessary.
, director of the infection department at Peking University's First Hospital, said these conditions were normal and there was no need to panic at all.
experts have also made it clear on different occasions that positive nucleic acid test results are still the "gold standard" for the diagnosis of viral infection.
Reporters noted that as of January 14 at 20 o's, Shijiazhuang City, the second round of nucleic acid testing has been completed;