The importance of wearing a mask is mainly to prevent the spread of the mask wearing illness - to those around it. In the East, this practice is known even before the appearance of the Corona virus among anyone who feels unwell or has signs of disease, to protect the environment in the public sphere. It is important to note that wearing a mask in the public space is not a good idea to protect yourself, in part because the simple mask protection capability, the most common among users (surgeon / surgical mask), is mediocre and insufficient - between 50% and 75% protection.

The second type of mask is N95 and provides about 95% protection. Therefore, this mask is suitable for those who wear it only on condition that they fit the mask well and tighten it. In practice, it is designed for the use of medical staff or people who are around patients who want to protect themselves. Some of these masks have a valve for airborne discharge of the wearer, which means that if he is ill he risks his environment.

In my estimation, if we were wearing masks earlier, it would have helped reduce the number of infections we currently record (for example, a person from overseas who infected people by train, taxi, etc. until he got to his home). The general public must wear masks in the public space, and those who visit a medical facility must wear a mask to protect the medical staff, which is a very expensive personnel at this time.

In my opinion, once they open the current closure and somewhat mitigate the existing restrictions, it is worth considering using the surgeon's mask so that if a person is ill and has no symptoms - he will not infect the environment. Also, in areas that have a lot of patients, it is pointless to go with this mask to the public space to reduce the risk of infecting other people.

It is important to remember that respiratory infectious disease can infect in one of two ways: one is a drop infection - through breathing, coughing or sneezing up to two meters from the person. The corona infects in this way, and some studies have shown that the corona virus can also remain as an aerosol - a smaller particle that can survive for several hours in the air.

One of the benefits of the simple mask is that it prevents the wearer from putting her hand on her lips or face.

In practice, such a mask is good for up to two hours or until it fills with moisture and gets wet, and then has to be replaced. So, in the end, if Israel wants people in the public sphere not to infect others - it should make sure that everyone has simple surgical masks, that is, provide a few such masks per person a day, which of course requires formal decision-making and accompanying preparation.

Brought to print: Dan Lavie

Dr. Yoav Yehezkeli is a professor of emergency management and disaster at Tel Aviv University and one of the founders of the epidemic treatment team