Source:
https://dushi.singtao.ca/toronto/健康/接触哪些动物容易染病？人和动物接触的界线在哪/
Home disinfection methods Learn about these to keep you away from infectious diseases!
Canadian Metro Network
February 21, 2020 16:25
With the increasing number of confirmed and suspected cases of new coronavirus pneumonia, various suggestions for personal protection measures have emerged. In addition to common protective measures such as wearing a mask and washing hands frequently, the issue of household disinfection has also received much attention.
A few days ago, a message proclaiming "Mr. Zhong Nanshan's anti-virus tricks" was widely spread on the Internet. It was stated that "washing the throat with fresh saline can prevent virus infection".
However, this news is not the opinion of Academician Zhong Nanshan, nor is there any scientific basis. Academician Zhong Nanshan's team openly rumored that salt water gargle is good for cleaning the mouth and throat and is helpful for pharyngitis. However, the area invaded by the new coronavirus is in the respiratory tract, and mouthwashing cannot clean the respiratory tract. Secondly, there are no research results suggesting that saline has a killing effect on the new coronavirus.
So what can we do with the increasingly important situation of virus protection?
Medical alcohol is most commonly used and is available for general occasions
The most common virus killer is medical alcohol.
According to the "Diagnosis and Treatment of Pneumonia Caused by a New Coronavirus (Trial Version 3)", 75% alcohol can effectively inactivate the virus. Therefore, under the general requirements of killing, such as ordinary daily necessities, medical alcohol can be used for disinfection. It is best to buy commercial medical alcohol directly, and it is difficult to master the concentration.
Note that white wine cannot be used as a disinfectant, let alone bathing!
Figure 丨 Weibo @ 游 识 猷
Medicinal alcohol refers specifically to 75% alcohol. Alcohol can denature proteins, so it has the effect of killing microorganisms. However, the low-concentration alcohol has a poor killing effect, and the high-concentration alcohol can cause the protein on the surface of the microorganism to solidify too quickly, and the alcohol cannot penetrate into it, and the effect is poor. Practical research has found that alcohol with a concentration of around 75% has a strong killing effect.
Bacteria and viruses are two different types of organisms. Medical alcohol has a strong killing effect on bacteria, but it may not be effective on viruses and may not be effective on many viruses. 2019-nCov can be killed by alcohol because of its protein envelope.
Hand Sanitizer and "Sterilizing Hand Sanitizer"
Wash your hands frequently with hand sanitizer or soap, and wash your hands with flowing water for more than 20 seconds. It has a certain effect on blocking the spread of the virus and can be used in combination with other protective measures. Hand washing methods can refer to effective prevention of pneumonia, proper hand washing and wearing a mask.
Among all hand washing products, hand sanitizers containing "fungicide" are particularly popular. However, like medical alcohol, the germicide in hand sanitizers is not necessarily effective against viruses. For new types of coronaviruses, there is no accurate research conclusion about how effective these fungicides are.
Common hand sanitizers generally use two types of fungicides (or bacteriostatic agents). One is chlorine-containing phenols. The representative substance is p-chloro-xylenol (PCMX). The other is quaternary ammonium salts. Representative substance is benzalkonium chloride (BAC). The common germicidal hand sanitizers on the market are almost all formulated from these two substances.
In some scientific tests, both PCMX and BAC can kill some viruses, such as common influenza viruses. However, the concentration used in experiments is often high, and the elimination effect is strongly related to the type of virus. For example, another common virus, HIV, these fungicides are just for fun.
The active ingredients of disposable hand sanitizers and hand disinfection products are relatively diverse, some are alcohol, some are cetrimonium chloride, hypochlorous acid, etc. They can be used as an alternative when it is not convenient to wash your hands with running soap and your hands are not significantly dirty.
Efficient and high destructive 84 disinfectant
In many people's homes, there is also a common type of disinfectant, which is 84 disinfectant.
The main component of 84 disinfection solution is hypochlorous acid (and hypochlorite). Its disinfection principle is strong oxidizing, which will cause many components in microorganisms to be oxidized and eventually lose their function, unable to reproduce or infect.
Similar to 84 disinfectant is chlorine dioxide. This is also a type of chlorine-containing disinfectant, which can also kill viruses with the help of strong oxidizing properties. At present, it is generally used as a disinfectant for tap water.
Because it has strong oxidizing properties, it also has a bleaching effect.
These disinfectants need to be diluted before use. When diluting, pay attention to the concentration (available chlorine content). In general household disinfection, you can refer to the instructions for disinfection solution to wipe and soak related items. Hypochlorous acid is unstable and easy to decompose. When using 84, pay attention to the expiration date; if you use a disinfection tablet for water, remember to use the "existing mix".
However, the use of chlorine-containing disinfectants is strongly irritating. Always follow the instructions when using, pay attention to ventilation, do not get in the eyes and contact the mucous membranes. Another side effect is that because they both generate chlorine atoms, if used on some metal materials, the chlorine atoms will cause long-term corrosion; some equipment related to circuits, such as mobile phone, computer and other equipment, use this type of disinfectant Need to be careful.
Also, it must be noted that 84 disinfectant solutions cannot be used with toilet cleaners. They will chemically generate chlorine gas, which will not only cause disinfection failure, but also the toxicity of chlorine gas will cause harm to the body.
Peracetic acid is cost-effective but has poor stability
During the SARS epidemic in 2003, many people heard about the prestige of peracetic acid, which became the main force for disinfecting public places.
From the perspective of molecular structure, peroxyacetic acid has only one more oxygen than acetic acid, which makes it super oxidizing and has the effect of sterilization. Under normal circumstances, peroxyacetic acid only needs to be formulated into an aqueous solution with a concentration of about 0.005%, which can be used for killing, and it can kill almost all viruses within one minute, and it is very efficient.
However, there is also a significant disadvantage of peroxyacetic acid, which is that it is less stable and easily decomposes. As a dangerous product, it is difficult to buy peracetic acid directly on the market, and for most people, it is not practical to prepare a peroxyacetic acid solution.
Peroxyacetic acid is also corrosive, so be careful when using it. However, it will not have a significant impact on all types of equipment in life.
Physical kill method, need to consider the occasion
Generally speaking, there are no more than two methods for physically killing viruses. One is to use light, usually ultraviolet light; the other is to use heat. Most viruses are sensitive to ultraviolet light and high temperatures.
Relatively speaking, high-temperature anti-virus has high operability in a domestic environment. For example, some items can be boiled in hot water, and clothing can be washed at the highest temperature indicated on the label. According to the guidance of the National Health Commission, heating at 56 ? C for 30 minutes can effectively kill the 2019-nCov virus.
Ultraviolet light is a simple method of disinfection. In the laboratory, it is usually only necessary to turn on the ultraviolet lamp to disinfect the operating table. However, the current domestic UV lamp equipment is usually not designed to kill, and the ultraviolet light they emit may not be suitable for killing viruses. In addition, the side effects of ultraviolet light are very large, it will produce many toxic and harmful substances such as ozone, and may directly cause harm to the human body (electrical ophthalmitis and dermatitis will occur after 20 minutes of exposure). Therefore, the use of UV lamps as a means of eliminating viruses is not recommended.
Other less common disinfectants
In addition to some of the common disinfection methods mentioned above, there are many substances or methods that can also be used to kill viruses, such as ether, chloroform, etc., which have also been identified as effective for new types of coronaviruses.
However, because these substances are often hazardous, such as ether, which is flammable and explosive, and chloroform can easily produce highly toxic phosgene when it is not stored properly, which can cause death. Therefore, they are difficult to purchase and extremely Recommended for non-professionals.
