Flying flocs can accelerate the spread of new crowns, and antigen testing can replace nucleic acid testing...
At the moment of the new crown pneumonia epidemic, do not add confusion to rumors
【Dispel rumors】
At a recent press conference held by the Joint Prevention and Control Mechanism of the State Council, Wu Liangyou, deputy director of the National Health Commission's Bureau of Disease Control and Prevention, said that in recent times, the national epidemic situation has gradually stabilized, but the impact of cross-input between regions is obvious. The task of dynamic clearing is very difficult.
Just as all parts of the country are striving to achieve the goal of social clearance as soon as possible, rumors about the new crown pneumonia epidemic continue to emerge.
Fei Xu can speed up the spread of the new coronavirus, antigen testing can replace nucleic acid testing, wearing a mask can blow out a lighter, which proves that the mask is ineffective... The appearance of these rumors makes people panic.
In order to clarify the fallacy and dispel doubts, the reporter of Science and Technology Daily interviewed relevant experts.
Can flying flakes accelerate the spread of the new coronavirus? Fact: There are no cases of infection caused by flying fluff
The pear blossoms are pale white and the willows are dark green, and when the catkins fly, the city is full of flowers.
It is said that April is the most beautiful day in the world, but when the spring flowers bloom, the difficult "flying season" in the north also comes.
The catkins flying all over the sky rushed towards the face, and it "drilled" into people's mouths and noses if they were not careful.
Therefore, some netizens take it for granted that since items that have been in contact with the new coronavirus may carry the virus, then the catkins flying in the air can also absorb the new coronavirus after contact with the droplets coughed up by the infected person. Dispersion accelerates infection of healthy people.
In this regard, Wu Zunyou, chief epidemiologist of the Chinese Center for Disease Control and Prevention, made it clear that in the past two years or more of research, it has not been found that flying fluff can adsorb viruses, and so far there has been no report on the infection caused by flying fluff.
Wu Youzun said that the new coronavirus is generally not transmitted directly from an infected person to a healthy person in the form of a free virus. The new coronavirus usually uses droplets as a carrier and is adsorbed on the surface of tiny droplet particles. Patients cough, sneeze, etc. The droplets are sprayed out, and the virus is adsorbed on the droplet particles and discharged together.
Droplets are generally small in size, with a particle size of 1 to 5 microns, and their transmission distance is 1 to 2 meters. When healthy people come into contact with droplet particles adsorbed with the new coronavirus, they may be infected.
"Actually, this is the principle of aerosol transmission." Chen Chunqi, a professor at the School of Life Sciences of Hubei University, said that if you are infected with the new coronavirus through flying floes, you need to meet very harsh conditions.
First of all, people infected with the new crown need to sneeze or cough towards the catkins, and the droplets that have absorbed the virus must also touch the catkins, and the new crown virus must reach a certain number, and the "poisonous" catkins must also accurately contact healthy people. respiratory tract infection.
Therefore, so far, there have been no cases of infection caused by flying fluff.
Although the fear of flying catkins accelerating the spread of the new coronavirus has been eased, the danger of droplets spreading the new coronavirus has to be guarded against. At the same time, in order to avoid pollen allergies caused by willow catkins and so on, it is recommended that the public must wear masks when going out.
After returning to the room, you should wash your hands first, wash your nose and face at the same time, and clean up the flying dust on your coat in time.
Can antigen testing replace 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 self-testing, it has been very popular with the public, and even at the beginning of the market, it appeared "empty in seconds" as soon as it was put on the shelves.
Many people feel that antigen testing is obviously more convenient than going to hospitals or communities for nucleic acid testing, and the testing can be done easily at home.
Many people even believe that antigen testing 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 at Peking University First Hospital, made it clear that antigen testing is a very important supplement to nucleic acid testing, and it is mainly used in people under control, those in home isolation or those under close control. However, antigen detection cannot replace nucleic acid detection, and its detection results cannot be used as a substitute for nucleic acid detection results.
"Antigen detection is to detect the antigenic protein outside the new coronavirus, while nucleic acid detection is to detect the RNA (ribonucleic acid) inside the new coronavirus." Chen Chunqi introduced that if the number of antigenic proteins on the surface of the virus is relatively small, the test result will be marked - "Xiaohong" bar" may not be displayed.
Nucleic acid detection needs to be done through amplification. Because of the amplification process, even if the number of nucleic acids is small, the number of nucleic acids will increase significantly after amplification, which greatly increases the accuracy of the test, but it also causes the detection time to be relatively short. long.
Both detection methods have their own advantages and disadvantages, but nucleic acid detection is still the "gold standard" for determining new coronavirus infection, and its status cannot be replaced by antigen detection.
At present, my country adopts the cross-screening mode of nucleic acid detection and antigen detection, which can not only detect those with strong positive infection of the new coronavirus earlier, but also will not miss those with weak positive infection, and realize early detection, early reporting, early isolation, and early detection. treat.
Wearing a mask can blow out the fire, indicating that the mask is invalid? The truth: It is too one-sided as a mask failure standard
Recently, a "quick verification method" for whether masks can block the new coronavirus has been circulating in the circle of friends.
In the related video, a person wears a mask to blow the flame of a lighter, and points out that if he can blow the fire while wearing a mask, it means that the mask he wears cannot block the new coronavirus and needs to be discarded.
The principle of this verification method is that if wearing a mask can blow out the flames, it means that the mask is already "full of loopholes", so that the airflow can easily pass through.
In this regard, Qian Xiaoming, a professor at the School of Textiles of Tianjin University of Technology, said that the reason why masks can block the virus mainly depends on melt-blown cloth, which uses polypropylene as the main raw material and is composed of microfibers.
The fiber diameter of the melt-blown cloth can reach 1 to 4 microns, and the pores of the melt-blown cloth formed are very small, and even the new coronavirus with a very small diameter cannot pass through.
At the same time, the microfiber of the 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 based on whether they can blow fire through masks.
"Because whether the fire can be blown out depends on the size of the fire, the distance it blows, and the way you wear a mask," he said.
"If you want to ensure the effectiveness of melt-blown cloth masks, you must first meet the following three conditions. First, you need to buy mask products marked with qualified production batch numbers and meet national standards in regular channels; second, you must wear masks correctly; Third, masks must be used correctly and cannot be used repeatedly." Qian Xiaoming said.
Anti-aging NMN is the "magic medicine" to cure the new crown? Fact: Case studies can't lead to a cure for Covid-19
Since the outbreak of the new coronary pneumonia, various unreliable "special drugs" for the treatment of new coronary pneumonia have been circulated every once in a while, including veterinary drugs, beverages, etc. Even garlic and realgar have been given the ability to cure new coronary pneumonia. effect.
Everyone will laugh at rumors that are obviously unreliable, but there is a recent article on the Internet that a Harvard MD used NMN to cure a severe patient with the new crown.
It is endorsed by Harvard University and involves the anti-aging "magic drug" NMN. This rumor sounds very credible, so it has attracted widespread attention.
NMN stands for nicotinamide mononucleotide, which is a nucleotide derived from ribose and nicotinamide.
It has been reported that NMN supplementation can increase the amount of nicotinamide adenine dinucleotide in cells, thereby improving the metabolic state of cells, and ultimately has an anti-aging effect.
The claim that "NMN cures the new crown" is 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.
Eight of them had positive nucleic acid test results, and blood tests showed that inflammatory factors in the patients had increased to varying degrees.
After receiving NMN treatment, the patient's symptoms were relieved, and the number of inflammatory factors also decreased.
"On the basis of this study alone, it is impossible to conclude that NMN can cure the new crown, because it is only a case study." Wang Yimin, deputy director of the Department of Critical Care Medicine of Tianjin Taida Hospital, said, "According to evidence-based medicine, the evidence of case studies is sufficient. Very low. Taking the new coronary pneumonia as an example, many patients can recover by themselves. On the surface, the patients involved in the study improved after taking NMN, but if they did not take NMN, would the patients also recover? This case Research cannot explain this critical question."
◎Our reporter Chen Xi