From the beginning of the COVID-19 pandemic, alongside the enormous humanitarian and medical effort, the scientific community came together to achieve as much information as possible about the virus and to identify control strategies for the infection. The result was the rapid development of several highly effective vaccines, some of them already adopted. Since the distribution of vaccines is currently underway and is heterogeneous among all countries, it remains still essential to understand the most efficacious measures to control the spread of the virus. By using an agent-based model we examine the efficacy of wearing face masks in combination with practicing social distancing. We explicitly consider a heterogeneous population of asymptomatic individuals and realistic values of face masks protection against viral transmission. Our simulations show that high compliance in social distancing is necessary to curb the spread of the infection and that wearing face masks provides the highest protection even if only a small population fraction are simultaneously practicing social distance. Finally, even if a large population fraction is asymptomatic, face mask effectiveness in controlling the viral spread is not reduced. In conclusion, our simulations demonstrate that the synergistic use of face masks and social distancing is the most effective intervention strategy for the infection.