Recently, everyone is very nervous, worried about
the new coronavirus infection, is it necessary to wear N95 masks?
Can ordinary medical surgical masks prevent new coronavirus? How to wear a mask? Now for everyone to do a homework on medical surgical masks.
American Medical Surgical Mask
Medical masks are usually called
Surgical Mask or Procedure Mask in English, and may also be called Dental Mask, Isolation Mask, Medical Face Mask, etc. In fact, they are the same. The name of the mask does not indicate which protective effect is better.
Although various English nouns actually refer to medical masks, there are often different styles. The traditional surgical masks used in the operating room are "Tie-On" bandages (above left), so many are called surgical masks. Surgical masks are also designed with straps. For ordinary people, the "Earloop" ear-hook medical mask will be more convenient to use.
CDC Anti-pandemic Mask Description
Medical surgical masks: not only prevent the wearer from spreading the germs, but also protect the wearer from spray and liquid splashes, and have a preventive effect on diseases spread by large particles of spray; but ordinary medical masks cannot filter small Particulate aerosol has no preventive effect on airborne diseases.
N95 masks: can block large particles of droplets and more than 95% of non-oily small particle aerosols. Properly wearing NIOSH certified N95 masks can prevent airborne diseases, and can be used as the lowest protective mask for airborne diseases such as TB tuberculosis and SARS However, N95 masks cannot filter gas or provide oxygen, and are not suitable for poisonous gas or low oxygen environment.
Surgical N95 mask: meets the N95 particle filtration standard, can prevent droplet transmission and airborne diseases, and can block the blood and body fluids that may occur during the surgery. FDA approved it as a surgical mask.
Can wearing a mask prevent the new coronavirus?
Experts believe that
the novel coronavirus (2019 Novel Coronavirus) is mainly spread by respiratory droplets, and can also be spread by contact.
Therefore, the transmission route of the new coronavirus is actually very similar to the transmission route of the influenza virus. In the case of not fully understanding
the new coronavirus, we can refer to some previous research data on whether wearing a mask can prevent the influenza virus.
Wearing a mask can help prevent viral infections
A study published in the International Journal of Infectious Diseases evaluated the risk of influenza infection among family members with children suffering from influenza-like illness, comparing N95 masks with ordinary medical masks and no gas density tests. (Non-fit-tested P2 masks) and three cases without wearing masks. The results of the study showed that family members who wear masks correctly have a 80% lower risk of influenza. However, there is no significant difference between the use of ordinary medical masks and N95 masks that have not tested gas density.
Another study in the Annals of Internal Medicine surveyed 400 people with influenza. The results showed that when you wash your hands frequently and wear masks, the risk of influenza in the family of patients is reduced by 70%.
A report from the University of Michigan is to study the effect of non-pharmaceutical interventions (NPI) on the prevention of influenza in the event of a vaccine shortage. The study surveyed more than 1,000 college students living in student dormitories, comparing "without special defense measures vs. The prevention effect of wearing a mask vs wearing a mask + washing hands frequently, the study found that wearing a mask alone cannot prevent influenza, but wearing a mask and washing hands frequently can reduce the risk of influenza by 75%.
In addition, a CDC study showed that patients wearing medical masks can greatly reduce viral aerosol emissions (reduced by 3.4 times), which can reduce virus copy number by 2.8 times for small particles smaller than 5 microns; for particles larger than 5 microns , Can reduce the virus copy number by 25 times.
It can be seen from the above that for the influenza virus and
the new coronavirus, the combination of wearing a mask and washing hands frequently can effectively reduce the possibility of transmission of the virus through droplets and contact, thereby reducing the risk of infection.
How to bring a medical surgical mask?
Medical masks usually have positive and negative blue and white sides, also known as blue and white masks. In fact, medical masks have at least three layers:
The outer layer is mostly blue or other colors, made of water blocking material, which can prevent liquid from entering the mask to its inside;
In the middle is the filter layer to block germs;
The inner layer is white, which can absorb moisture and absorb moisture during exhalation.
Therefore, when wearing a mask, you should face the white side to yourself, and the colored side to the outside to have a protective effect.
Correctly wearing medical surgical mask:
Clean your hands before wearing a mask;
Choose a mask that fits your size, put the metal strip on the side of the mask upward, hang the elastic bands on the back of the ear, and then fully expand the outer folding surface to ensure that the mask completely covers the mouth, nose and chin, and then press the metal strip with both hands. Nose clip to make the mask fit the face completely;
Try not to touch the mask again after wearing the mask. If you must touch it, you should wash your hands before and after;
When removing the mask, try not to touch the outer layer of the mask, you should pull the elastic band from behind the ear to remove the mask;
Masks should be discarded and put in the trash bin after use, and the hands should be washed immediately. Medical masks are disposable and do not be reused.
When to wear a mask:
When approaching a sick person, wear a mask before 6 feet / 2 meters (data shows that flu patients can infect people within 6 feet of them);
If you are sick, you should wear a medical mask before approaching others;
If you have symptoms of infectious diseases such as flu or new pneumonia, you should wear a medical mask when you go to the doctor to prevent the spread of bacteria.
If there are many people around with coughing and sneezing symptoms, wearing a mask can also prevent yourself from being sprayed by droplets, but medical masks cannot filter small aerosols suspended in the air. That is to say, when walking on an empty street and there are no people nearby, there will be no difference in the effect of wearing a medical mask.
How long can a medical mask be worn?
It is generally recommended that ASTM certified medical surgical masks be used continuously for no more than 4 hours, because the protective effect will decrease with time. In addition, when the medical mask becomes wet, dirty or damaged and falls off, it will also affect the protection effect, and all new masks should be replaced.
Medical masks should be discarded in trash cans with lids after use to reduce the chance of germs spreading.
Disposable masks should not be reused. After cleaning, sterilizing and disinfecting with water, heating, alcohol and other chemicals, ultraviolet light, etc., it is likely to damage the waterproof layer and filter layer of the mask. Testing is generally not recommended. However, in the case of shortage of materials, the method of choosing dry heating or ultraviolet disinfection masks is relatively more reliable.
In addition to paying attention to personal hygiene, you should also pay attention to the hygiene of your home and work environment. Especially when someone is sick around you, you should touch the surface of some objects that your hands often touch, such as mobile phones, mouse keyboards, desktops, door handles, refrigerator door handles, light switches, TV remote controls, toilet flush handles, faucets, etc. Sterilize and disinfect with alcohol or disinfectant wipes at least once a day.
