Individuals with no or mild symptoms at the pre-symptomatic and early stages of infection may contribute to the spread of COVID-19. A face mask may help reduce the spread of infection in the community by minimising the excretion of droplets from such individuals who may not even know that they are infected. Therefore, the use of face masks in the community may primarily serve as a means of source control which is relevant in epidemic situations where the number of asymptomatic but still infectious persons in the community may be significant.