The number of confirmed cases of covid-19 globally has exceeded 100 million, reaching 100,203,700, and the cumulative number of deaths has exceeded 2.14 million, reaching 2,147,411.
Among them, the epidemic in Europe and the United States is particularly serious. The number of confirmed cases in the United States has reached more than 26 million, and the death toll has exceeded 430,000. Although the number of new cases in a single day has fallen from before, it still reaches more than 150,000.
The number of confirmed cases in the UK has reached 3.58 million, with more than 100,000 deaths, and the current epidemic situation is continuing to deteriorate. Due to the severe epidemic in the United Kingdom and the emergence of mutant strains of the new crown virus, many European countries including France, Germany, and Italy have blocked the United Kingdom, banning British travelers from entering the country, and even in the trade of some goods, the United Kingdom has also been blocked. The current Britain has become the "sick man of Europe", and all countries are trying to stay away from Britain.
Why is covid-19 raging in Europe and America?
First of all, Europeans and Americans like to gather. The United States has just gone through the baptism of the general election, the US general election, various parades, various gatherings, various speeches, and tens of thousands of times, which greatly increased the gathering and flow of people. The increase in the epidemic in the United States is directly related to the general elections. Coupled with the arrival of the American New Year, that is, Christmas, the population movement and relative movement have increased, which has accelerated the population flow and caused the epidemic to continue to spread. During the Christmas period, the European population also moved in large numbers.
Secondly, in winter, the weather in the United States is even colder, making the virus more active and also leading to the accelerated spread of the epidemic. Many people place their hopes on the vaccine. When the vaccine has not yet been widely used and the effect of the vaccine is unknown, they have relaxed their vigilance and paid no attention to the epidemic, and even did not wear a mask. Therefore, the virus came in.
Finally, Europeans and Americans advocate freedom, and they don't like to wear masks, and even hold parades and other gathering activities, which undoubtedly provide conditions for the growth of the virus.
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At present, the most effective method of epidemic prevention is to wear a mask
In recent weeks, the growth rate of the U.S. epidemic has declined, thanks to the U.S. policy of maintaining social distancing and mandatory wearing masks.
American infectious disease expert Fauci said that wearing two layers of masks to resist the new crown virus is more effective than wearing one layer of masks, which is "common sense." A mask is a physical covering that can prevent droplets. If you have a physical covering, and then cover with another layer, it will be more effective. In an interview with the NBC news program "Today", he said that wearing two layers of masks at the same time provides more protection than just wearing one.
Dr. Marybeth Sexton, assistant professor of infectious disease at Emory University School of Medicine in Atlanta, agrees with Fauci. She said that the new variant virus "may cause patients to have more virus in their nose and mouth, so when they breathe, talk, cough or sing, they may release more virus particles into the environment than ordinary people. "
Sexton added, "If everyone is wearing a mask, this shouldn't be a big problem."
In response to the outbreak, Dr. Scott Segal, director of anesthesiology at Wake Forest Baptist Health in Winston-Salem, North Carolina, has been studying facial masking for most of the past year.He said that three-layer medical surgical masks often provide the best protection for ordinary people. For those who choose cloth masks, it is recommended to use two layers of high-quality cotton material with high weft density.
An easy way to test the effectiveness of a cloth mask at home is to point it at the light. If light shines between the individual fibers of the cloth, it may mean that virus particles can also pass through, and such masks are ineffective.
In short, even if there is a vaccine as a guarantee, the most effective means of preventing the epidemic is still wearing a mask.（try Suntech mask machine）
Where do we have to wear masks?
【indoor】
1. Foreign immigrants should wear masks when conducting home isolation medical observation; family members should wear masks when in close contact with home isolation medical observation personnel.
2. When family members suffer from respiratory-transmitted diseases, they should wear masks and seek medical treatment in time.
3. The family room should be ventilated. In daily situations, family members do not need to wear masks.
【Guesthouse, Hotel】
1. When consumers enter public areas such as hotels and hotel lobbies, they should wear masks and consciously maintain a social distance of more than one meter from others.
2. Consumers do not need to wear masks after entering their guest rooms.
3. Hotel and hotel staff should wear masks throughout the work period.
【Shopping malls, supermarkets】
1. Consumers should wear masks all the time when they enter the mall for shopping and consumption; after shopping, they can leave the mall or supermarket and enter the outdoor environment without wearing a mask.
2. The staff of shopping malls and supermarkets should wear masks throughout the work period.
【restaurant】
1. Consumers should wear masks after entering the restaurant.
2. Wear a mask when ordering food in a restaurant and calling service personnel for service.
3. Consumers can remove their masks during meals, avoid or reduce conversations as much as possible, and encourage the use of public chopsticks and spoons.
4. After the meal, you should wear a mask and leave.
【Outdoor activity】
1. You should not wear a mask during single-person outdoor activities such as outdoor running.
2. When playing badminton, table tennis, tennis and other sports, due to the long distance between the two parties, it is not necessary to wear a mask.
3. When engaging in violent confrontational sports such as basketball, it is not necessary to wear a mask if the temperature of the participants is not abnormal, and conversations should be avoided during the exercise.
[Indoor environment in other public places]
1. Consumers should wear masks all the time when entering public places; after leaving public places and entering the outdoor environment, they do not need to wear masks.
2.Workers in public places should wear masks throughout the work period.
How do masks play a role in epidemic prevention?
How does the mask work:
(1) Diffusion deposition: Brownian motion of particles diffuses and shifts to filter fibers, and is adsorbed by molecular gravity. It is easiest to capture small-scale particles, fine fibers and low-speed particles.
(2) Retained deposition: The larger particles moving with the airflow are retained by the mechanical sieving effect of the filter material. The ratio of the particle diameter to the diameter of the filter membrane fiber affects the interception efficiency.
(3) Inertial deposition: When particles pass through the curved mesh channel of the filter material, the particles escape from the airflow and hit the filter fiber due to inertia, and are trapped by molecular gravity. The trapping effect is good when large particles, high density and high speed.
(4) Electrostatic attraction and deposition: The particles are deposited by the electrostatic action of the filter fiber.
The smaller the particles, the stronger the sedimentation effect of 1, 4, and the larger the particles, the better the effects of 2, 3, so the smaller the particles, the more difficult it is to filter. Synergistic effects of various filtration mechanisms, the most easily penetrated particle size range of ordinary mechanical filter media is 0.1m-0.3m.
Mask components
Medical masks generally have a three-layer (non-woven) structure. They are made of two layers of spunbond non-woven fabrics that are professionally used for medical and health care, and a layer of meltblown non-woven fabrics with filtration and antibacterial filtration of more than 99.999% are added in the middle. It is made by ultrasonic welding.（try Suntech Melt blown machine）
The three-layer decomposition of medical masks: the outer layer has an anti-droplet design (spunbond non-woven fabric) + middle layer filtration (meltblown non-woven fabric) + moisture absorption of the inner layer (spunbond non-woven fabric).
(1) Spunbond non-woven fabric (outer layer): mechanically isolate dust and large particles in the air through fiber pores.
Advantages: ventilation, filterability, water absorption, water resistance, good hand feeling, softness and lightness
Disadvantage: Cannot be cleaned
(2) Melt-blown non-woven fabric (middle layer):
The main material is polypropylene, which is a kind of ultra-fine electrostatic fiber cloth, which can capture dust and germs. When the droplets containing covid-19 are close to the meltblown non-woven fabric, they will be electrostatically absorbed on the surface of the non-woven fabric and cannot penetrate. This is the key layer for the mask to play the role of bacteria isolation.
(3) Spunbond non-woven fabric (inner layer): absorbs the liquid and moisture released by the wearer, and avoids the effect of moisture penetrating the mask from affecting its protective effect. Prevent droplets from coughing out and affecting the surrounding environment.
Advantages: ventilation, filterability, water absorption, water resistance, good hand feeling, softness and lightness
Disadvantage: Cannot be cleaned
Nose bridge strip: It is a thin rubber strip inside the mask, which plays the role of fixing the mask on the bridge of the nose. The use of environmentally friendly plastic strips does not contain any metal, and is breathable and comfortable.
How to judge whether the mask contains melt blown cloth?
The key layer of the mask is the meltblown cloth layer with electrostatic adsorption in the middle. If the static electricity is lost, the anti-epidemic effect of the mask will also decrease. When the meltblown layer encounters water, the electrostatic adsorption effect will be greatly reduced, so pay attention to waterproofing. The method to check whether the melt blown cloth is effective is as follows:
(1) Cut the mask open and see whether the meltblown layer can absorb small pieces of paper, because the electret meltblown cloth has electrostatic adsorption, but it is difficult to detect what level the mask can reach.
(2) Melt blown cloth will melt in fire and will not burn. You can tear the middle layer of the open cover and burn it with a lighter. If it does not burn, it is usually melt blown cloth.
(3) Tear the melt blown layer into strips, there will be obvious electrostatic adsorption effect, and the strips of melt blown layer can also be adsorbed on the stainless steel.
(4) You can pour a little water on the melt blown cloth, it is a better melt blown cloth that does not leak.
(5) Testing with professional testing equipment.
With 50 years of technical precipitation and manufacturing experience, Suntech has carefully developed and designed intelligent mask machines and meltblown machines, which have high production efficiency, save labor, and help human health with "precision and intelligent manufacturing".
