In the context of an unprecedented event such as the COVID-19 pandemic, at present, the effectiveness of stringent social distancing and international traffic-related measures in decreasing the rate of spread of SARS-CoV-2, and related mortality, is inferred from empiric observations of their application in countries experiencing different transmission scenarios (e.g., Australia, China, Germany, Italy, New Zealand, and Spain). Such observations are consistent with and corroborated by mathematical models.