In this study done at UNC Chapel Hill, researchers found that the SARS-CoV-2 virus first infects the body through the nose, establishes itself there, and then progresses into the airway and lungs.
Hou, Y. J., et al., (2020). SARS-CoV-2 Reverse Genetics Reveals a Variable Infection Gradient in the Respiratory Tract. Cell, 182(2), 429-446.e14.