face mask in corona virus era

1. in parts of Asia: compulsory and necessary.

1.1. safer and considerate

1.2. solidarity

1.3. protect invididuals and other

1.4. polite, respect other

1.5. Czech

1.6. pollution affects health.

2. social nudge

2.1. ritual and more hygienic behaviour

2.2. small activities well effect on society

2.3. reusing when lack mask

2.4. being criticised for lacking precaution

2.5. in West, pp can be attacked or shunned if wearing mask.

3. undocumented cases

3.1. silent carriers

3.2. prevailing wrong belief

4. different among countries.

5. WHO: subjects should wear and don't need to

5.1. should

5.1.1. sick and having symptom pp

5.1.2. responsible for taking care of suspected pp

5.2. don't need

5.2.1. everyone else