At present, the COVID-19 epidemic situation, rumors don’t add chaos.

　　Photo courtesy of people’s vision

　　[rumor]

　　Wu Liangyou, deputy director of the National Health Commission Municipal Bureau of Disease Control and Prevention, said at the recent press conference of the joint prevention and control mechanism in the State Council that the epidemic situation in the whole country has gradually stabilized, but the cross-input between regions has obvious influence, and the task of dynamically clearing all regions is very arduous.

　　While all parts of the country are working hard to achieve the goal of zero social coverage as soon as possible, rumors about the COVID-19 epidemic are constantly emerging. Flying catkins can accelerate the spread of Covid-19, antigen detection can replace nucleic acid detection, and wearing a mask can blow out a lighter, which proves that the mask is invalid … … The appearance of these rumors made people panic. In order to clarify the fallacy, solve doubts and doubts, the reporter of Science and Technology Daily interviewed relevant experts.

　　Can flying catkins accelerate the spread of Covid-19? Truth: There are no cases of infection caused by flying flocs.

　　Such as snow pear light white, wicker reveals the rich spring, fluttering sasa entrainment with such as snow pear, full of the city. It is said that April is the most beautiful day on earth, but when spring blossoms, the tough "flying season" in the north has also come. Catkin flying all over the sky comes to my face, and it "drills" into people’s mouths and noses if you are not careful.

　　As a result, some netizens take it for granted that since everything that has been exposed to Covid-19 may carry the virus, catkins flying in the air can also adsorb Covid-19 after contacting with droplets coughed up by infected people in Covid-19, which will accelerate the infection of healthy people with its dispersion.

　　In this regard, Wu Zunyou, chief epidemiologist of China Center for Disease Control and Prevention, made it clear that in the past two years or so, it has not been found that flying flocks can adsorb viruses, and so far, there has been no report on the infection caused by flying flocks.

　　Wu Youzun said that Covid-19 generally does not directly infect healthy people from an infected person in the form of a free virus. Covid-19 usually uses droplets as a carrier and adsorbs them on the surface of tiny droplets. Patients cough and sneeze the droplets, and the virus is adsorbed on the droplets and discharged together. Droplets are generally small in size, with a particle size of 1-5 microns and a propagation distance of 1-2 meters. When healthy people come into contact with Covid-19-adsorbed droplets, they may be infected.

　　"In fact, this is the principle of aerosol transmission." Chen Chunqi, a professor at the School of Life Sciences of Hubei University, said that if Covid-19 is infected by flying flocs, very harsh conditions are required. First of all, infected people in COVID-19 need to sneeze or cough toward catkins, and the droplets adsorbed with the virus have to stick to catkins. Moreover, in order to reach a certain number of Covid-19, this piece of "poisonous" catkins must accurately touch the respiratory tract of healthy people before infection can occur. Therefore, so far, there are no cases of infection caused by flying flocs.

　　Although the fear of speeding up the spread of flying catkins in Covid-19 has been relieved, the danger of flying catkins spreading to Covid-19 has to be prevented. At the same time, in order to avoid pollen allergy caused by flying catkins in willow, it is suggested that the public must wear masks when going out. After returning indoors, you should wash your hands first, clean your nose and face at the same time, and clean up the flying flocks left on your coat in time.

　　Can antigen detection replace nucleic acid detection? Truth: nucleic acid testing is still the "gold standard"

　　COVID-19 antigen test kit, which can be used for home self-test, has been well received by the public since it was put on sale. Even at the beginning of the market, it was "empty" as soon as it was put on the shelves. Many people think that antigen testing is obviously more convenient than going to hospitals and communities for nucleic acid testing, and testing can be easily completed at home. Many people even think that antigen testing can completely replace nucleic acid testing. Is this idea reliable?

　　At the press conference held by the State Council Joint Prevention and Control Mechanism, Wang Guiqiang, director of Infectious Diseases Department of the First Hospital of Peking University, made it clear that antigen testing is a very important supplementary means of nucleic acid testing, which is mainly carried out in the controlled population, the isolated population at home or the tightly controlled population, but antigen testing cannot replace nucleic acid testing, and its test results cannot be used as a substitute for nucleic acid testing results.

　　"Antigen detection is to detect antigen proteins outside Covid-19, while nucleic acid detection is to detect RNA (ribonucleic acid) inside Covid-19." Chen Chunqi introduced that if the number of antigen proteins on the surface of the virus is relatively small, then the test results identify — — The "little red bar" may not be displayed. However, nucleic acid detection needs to be completed by amplification, because with the amplification link, even if the number of nucleic acids is small, the number will increase greatly after amplification, which greatly increases the accuracy of detection, but it also causes a long detection time.

　　The two detection methods have their own advantages and disadvantages, but nucleic acid detection is still the "gold standard" to determine Covid-19 infection, and its position cannot be replaced by antigen detection.

　　At present, China adopts the screening mode of crossing nucleic acid detection and antigen detection, which can not only find the strong positive infected people in Covid-19 earlier, but also realize early detection, early reporting, early isolation and early treatment.

　　Wearing a mask can blow out the flames, which means that the mask is invalid? Truth: It is too one-sided to use this as a mask failure standard.

　　Recently, a "quick verification method" has been circulating in the circle of friends to see if a mask can block Covid-19. In the related video, a person wears a mask to blow the flame of a lighter, and points out that if he can blow out the flame with a mask, it means that the mask he wears cannot block Covid-19 and needs to be discarded.

　　The principle of this verification method is that if wearing a mask can blow out the flame, it means that the mask is "full of loopholes" and the airflow will pass easily.

　　In this regard, Qian Xiaoming, a professor at tianjin polytechnic university Textile Institute, said that the reason why masks can stop viruses mainly depends on meltblown cloth, which is made of polypropylene and consists of superfine fibers. The fiber diameter of the meltblown fabric can reach 1 to 4 microns, and the holes formed in the meltblown fabric are so small that even the Covid-19 with a very small diameter cannot pass through. At the same time, the superfine fiber of meltblown cloth has a large specific surface area and a strong electret charge, so it can easily absorb viruses and dust.

　　Qian Xiaoming believes that it is one-sided to judge the effectiveness of masks only by whether they can blow out the flames through them. "Because whether you can blow out the flame is related to the size of the flame, the distance you blow and the way you wear a mask." He said.

　　"If you want to ensure the effectiveness of the meltblown cloth mask, you must first meet the following three conditions. First, it is necessary to purchase mask products marked with qualified production batch numbers and meeting national standards in formal channels; Second, wear a mask correctly; Third, it is necessary to use the mask correctly and not use it repeatedly. " Qian Xiaoming said.

　　Is anti-aging NMN the "magic medicine" to cure COVID-19? Truth: The case study can’t reach the conclusion of curing COVID-19.

　　Since the outbreak of the COVID-19 epidemic, every once in a while, various unreliable "specific drugs" have been circulated to treat COVID-19, including veterinary drugs, drinks and so on. Even garlic and realgar have been endowed with the efficacy of curing COVID-19.

　　Everyone will laugh at the obviously unreliable rumors, but recently there was an article on the Internet saying that the medical doctor of Harvard University used NMN to cure the seriously ill patients in COVID-19. It is also endorsed by Harvard University and involves the anti-aging "magic medicine" NMN. This rumor sounds very credible, so it has aroused widespread concern.

　　The full name of NMN is nicotinamide mononucleotide, which is a nucleotide derived from ribose and nicotinamide. It has been reported that NMN supplementation can increase the number of nicotinamide adenine dinucleotide in cells, thus improving the metabolic state of cells and finally playing an anti-aging role.

　　The statement that NMN cured COVID-19 was mainly based on a paper published by Dr. Robert, an American doctor. In this study, 10 patients were treated with NMN, and they all had symptoms such as fever and cough. Among them, 8 nucleic acids were positive, and blood tests showed that the inflammatory factors in the patient’s body increased to varying degrees. After receiving NMN treatment, the patient’s symptoms were relieved and the number of inflammatory factors decreased.

　　"Based on this study alone, it is impossible to conclude that NMN can cure COVID-19, because it is only a case study." Wang Yizhen, deputy director of the Department of Critical Care Medicine of Tianjin TEDA Hospital, said, "According to evidence-based medicine, the evidence sufficiency of case studies is very low. Take COVID-19 as an example, many patients can heal themselves. On the surface, the patients involved in the study got better after taking NMN, but can they recover if they don’t take NMN? This kind of case study cannot explain this key issue. "

　　(The pictures in this article are all from vision china except the labeling.)