Wearing a mask is a great way to slow transmission and save lives, but masks alone cannot prevent every case. Personal protective equipment can be prone to human error or inconsistent use, and it is less effective when people are in close contact over a long period of time.
How Widespread Quarantine Works
Complete quarantines, where everyone in a geographic area stays isolated regardless of their infection status, can stop the spread of COVID-19 in its tracks. However, this can be difficult to maintain over the long term without major disruptions to essential services and economic activity.
How Manual Contact Tracing Works
Contact tracing allows for a smarter, more targeted quarantine, where only those who came into contact with an infected person are required to isolate themselves. However, it can be very difficult to discover and notify every person who may have been exposed.