The problem is that a “border run” requires exiting Costa Rica, and entering another country, typically at the land border with Panama or Nicaragua. Effective 11:59 pm on Monday, Panama will close it’s borders to foreigners. At present, information from the Ortega regime in Nicaragua is vague and does not address border closures or foreigners. Officials at land borders in Central America also have a tendency toward making arbitrary decisions.
Leaving Costa Rica offers no guarantee of re-entry for a foreigner, and those lacking an entry and exit stamp from the adjacent country may find themselves in an irregular situation; unable to travel outside of the immediate border area.
In other words, once you have “stamped out” of Costa Rica, it is normally prohibited to “stamp back into” Costa Rica, until having gone through the entry and exit process in either Nicaragua or Panama. However, as the last few days have demonstrated, in the face of the Pandemic, what is “normal” is subject to change. Should border officials or the military in Nicaragua decide that a foreigner is at risk or showing symptoms then what is the recourse? Could a traveler find themselves standing on the border of two countries, neither of which will accept their entry?
Getting on a crowded bus and standing in lines at a crowded border crossing is a not a prudent course of action, especially for the elderly or those most at risk from the COVID-19 virus. Americans who intend to stay in Costa Rica for the Pandemic should stay put. Otherwise, right now would be a good time to get on a flight to the United States.