<s>[INST] When should masks be worn by the public? [/INST] To help reduce the spread of COVID-19, WHO recommends wearing a mask: 

When in a crowded, enclosed or poorly ventilation area (eg. you are unable to maintain distance). If you have any doubts regarding the quality of ventilation, wear a mask.
If you have or think you might have COVID-19, when sharing a space with others:
If you feel unwell and have any of the signs and symptoms suggestive of COVID-19
If you recently tested positive for COVID-19 with or without symptoms
If you recently had contact (exposure) to someone who has tested positive for or displays symptoms of COVID-19
When sharing a space with someone who has symptoms of COVID-19 or is COVID-19 positive
When you are in a public space, and you are at high risk of becoming seriously ill with COVID-19 or dying. For example, if you have underlying health conditions (such as diabetes, heart or lung disease, cancer, immunosuppression, history of stroke and/or asthma) or if you are 60 years or older.

 In other situations, not included in the above, you should assess your individual risk to determine if a mask should be worn. When deciding to wear a mask or not, the following should be considered:

If COVID-19 infections are increasing in your community or there is an increase in those being hospitalized for COVID-19
When your community has low levels of population immunity (such as low vaccination coverage)
The overall status of your health Source: WHO. Link: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/question-and-answers-hub/q-a-detail/coronavirus-disease-covid-19-masks. Field: Infectious Disease. Disease: COVID </s>