At a recent press conference held by the joint prevention and control mechanism of the State Council, Wu Liangyou, deputy director of the Disease Control Bureau of the National Health commission, said that in recent times, the national epidemic situation has gradually stabilized, but the impact of cross-input between regions is obvious, and the task of dynamic zero clearance in various places is very arduous.
While the whole country is working towards the goal of zeroing out social coverage as soon as possible, rumors about the COVID-19 pandemic continue to emerge. Flying feathers can accelerate the spread of the new crown virus, antigen testing can replace nucleic acid testing, wearing a mask can blow out the lighter proves that the mask is ineffective... The appearance of these rumors has caused panic. In order to clarify the fallacy and solve the doubts, the reporter of Science and Technology Daily interviewed relevant experts.
Can Flying Accelerate the Spread of COVID-19?
Truth: There are no cases of infection caused by flying feathers
The pear blossoms are pale white and the willows are dark blue, and the flowers are full of flowers when the willows fly. It is said that the most beautiful April day on earth, but when the spring flowers bloom, the difficult "flying season" in the north also comes. The willows flying in the sky rushed to the face, and if they were not careful, they "drilled" into people's mouths and noses.
Therefore, some netizens take it for granted that since the items that have been exposed to the new crown virus may carry the virus, the willow fluttering in the air and the droplets coughed out by the new crown virus infected people can also adsorb the new crown virus after contact, and accelerate the infection of healthy people with its dispersion.
In this regard, Wu Zunyou, chief expert of epidemiology at the Chinese Center for Disease Control and Prevention, made it clear that in the past two years of research, no fly can adsorb the virus, and so far there have been no reports of infection caused by fly feathers.
Wu Youzun said that the new crown virus generally does not spread directly from an infected person to a healthy person in the form of a free virus, the new crown virus usually uses droplets as a carrier, adsorbed on the surface of tiny droplet particles, patients spray droplets by coughing, sneezing, etc., and the virus is adsorbed on the droplet particles and discharged together. Droplets are generally small in size, usually 1 to 5 microns in size, and their transmission distance is 1 to 2 meters, and when healthy people come into contact with droplet particles that adsorb the new crown virus, they may be infected.
"Actually, this is how aerosols spread." Chen Chunqi, a professor at the School of Life Sciences of Hubei University, said that if you are infected with the new crown virus through flying feathers, you need to have very harsh conditions. First of all, the new crown infected people need to sneeze or cough towards the willow, the droplets that adsorb the virus must also be stained on the willow, and the new crown virus must reach a certain number, and this "poisonous" willow must also accurately contact the respiratory tract of healthy people before infection can occur. As a result, there have been no cases of infection caused by flying feathers to date.
Although the fear of accelerating the spread of the new crown virus has been lifted, the risk of droplet transmission of the new crown virus must also be prevented, and in order to avoid pollen allergies caused by willow flying feathers, it is recommended that the public must wear a mask when going out. When you return indoors, you should wash your hands first, wash your nose and face at the same time, and clean up the flying feathers that fall on your coat in time.
Can antigen testing be an alternative to nucleic acid testing?
The Truth: Nucleic Acid Testing Is Still the "Gold Standard"
Since the launch of the new crown antigen detection kit that can be used for home testing, it has been quite popular with the public, and even at the beginning of the listing, there was a situation of "seconds and empty" as soon as it was on the shelves. Many people feel that antigen testing is obviously more convenient than going to the hospital and community for nucleic acid testing, and the "home" can easily complete the test at home. Many people even think that antigen detection can completely replace nucleic acid testing, is this idea reliable?
At a press conference held by the joint prevention and control mechanism of the State Council, Wang Guiqiang, director of the Department of Infectious Diseases of the First Hospital of Peking University, made it clear that antigen detection is a very important supplementary means of nucleic acid testing, mainly in controlled groups, home isolation groups or closely controlled groups, but antigen testing cannot replace nucleic acid testing, and its test results cannot be used as a substitute for nucleic acid test results.
"Antigen testing is to detect antigenic proteins outside the new crown virus, while nucleic acid testing is to detect the RNA (ribonucleic acid) inside the new crown virus." Chen Chunqi introduced that if the number of antigen proteins on the surface of the virus is relatively small, then the test result identification - "small red bar" may not be displayed. 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 of amplifications will increase significantly, which greatly increases the accuracy of the test, but this also causes a long detection time.
Both tests have advantages and disadvantages, but nucleic acid testing is still the "gold standard" for determining COVID-19 infection, and its status cannot be replaced by antigen testing.
At present, the mainland adopts the screening mode of nucleic acid detection and antigen detection crossover, which can not only detect strong positive infections of the new crown virus earlier, but also will not miss weak positive infections, and achieve early detection, early reporting, early isolation and early treatment.
Can wearing a mask blow fire extinguishing a flame indicate that the mask is ineffective?
Truth: This is too one-sided as a standard for mask failure
Recently, there is a "rapid verification method" in the circle of friends about whether masks can block the new crown virus. In the relevant video, a person wearing a mask blows the flame of a lighter, and points out that if he can wear a mask to blow the flame, it means that the mask he wears cannot block the new crown virus 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 has been "full of loopholes" and will allow the air flow to pass easily.
In this regard, Qian Xiaoming, a professor at the School of Textiles of Tianjin Polytechnic University, said that the reason why masks can block the virus is mainly based on meltblown cloth, which uses polypropylene as the main raw material and is composed of microfibers. Meltblown cloth fibers can reach 1 to 4 microns in diameter, forming a meltblown cloth hole that is so small that even the new coronavirus with a very small diameter cannot pass through. At the same time, the microfibers of meltblown cloth have a large specific surface area and a strong electret charge, so they can easily adsorb viruses and dust.
Qian Xiaoming believes that judging the effectiveness of masks is one-sided only based on whether they can blow fire extinguishers through masks. "Because whether you can blow out the flames is related to the size of the flames, the distance it blows, and the way you wear a mask." He said.
"If you want to ensure the effectiveness of meltblown cloth masks, you need to first meet the following three conditions. First, it is necessary to purchase mask products marked with qualified production batch numbers and in line with national standards through formal channels; second, masks should be worn correctly; third, masks should be used correctly, and they should not be used repeatedly. Qian Xiaoming said.
Anti-aging NMN is the "miracle drug" to cure the new crown?
Truth: Case studies cannot conclude that there is a cure for COVID-19
Since the outbreak of the new crown pneumonia epidemic, every once in a while there will be a variety of unreliable "special drugs" for the treatment of new crown pneumonia, including veterinary drugs, drinks, etc., and even garlic and male yellow have been given the effect of curing new crown pneumonia.
For the obviously unreliable rumors, everyone will laugh at it, but recently there is an article on the Internet that Harvard University's medical doctor used NMN to cure the new crown patients. It is also endorsed by Harvard University, and it involves the anti-aging "miracle drug" NMN, which sounds very credible and has attracted widespread attention.
NMN, known as nicotinamide mononucleotide, is a nucleotide derived from ribose and nicotinamide. It has been reported that NMN supplementation can increase the number of intracellular nicotinamide adenine dinucleotides, thereby improving the metabolic state of cells and ultimately playing an anti-aging role.
The main basis for the "NMN cure for the new crown" is a paper published by Dr. Robert, an American doctor. In the study, 10 patients were treated with NMN, and they all had symptoms such as fever and cough. Among them, 8 of them had positive nucleic acid test results, and blood tests showed that the inflammatory factors in the patient's body had increased to varying degrees. After receiving NMN treatment, the patient's symptoms were relieved and the number of inflammatory factors decreased.
"This study alone cannot conclude that NMN can cure COVID-19, because it is only a case study." Wang Yimin, deputy director of the Department of Critical Care Medicine at Tianjin TEDA Hospital, said, "According to evidence-based medicine, the evidence adequacy of individual studies is very low. In the case of COVID-19, many patients can heal themselves. On the surface, the patients involved in the study improved after taking NMN, but if they did not take NMN, could the patients also be cured? Such case studies cannot explain this critical issue. ”
Sichuan Observation (Source: CCTV News)