| findings | explain | geographic spread of COVID-19 (count: 1) | |
|---|---|
| These findings explain the rapid geographic spread of COVID-19 and indicate containment of this virus will be particularly challenging.
| |
| infections | geographic spread of | COVID-19 (count: 1) | |
| This finding indicates that contagious, undocumented infections facilitated the geographic spread of COVID-19 within China.
| |