How many of them are medical workers who escaped from Venezuela...?

Cubans stranded in Costa Rica, blame falls on U.S. Cuban Adjustment Act
by: W. T. Whitney Jr.
December 7 2015

A dispute between Nicaragua and Costa Rica over the fate of Cuban migrants heading to the United States highlights the injustice and unfairness of the U. S. Cuban Adjustment Act (CAA) of 1966. Through that law, any Cuban citizen arriving on U.S. soil gains permanent residence after a one-year stay. The legislation has served U. S. propaganda purposes by creating a flood of immigrants ready to be portrayed as refugees fleeing political repression.

According to the Pew Research Center, 15,341 Cubans arrived in the United States during the first nine months of fiscal 2014 and 27,296 during the comparable period of fiscal 2015, a 78 percent increase. The burgeoning number of people leaving Cuba, primarily for economic reasons, stems from fear that the CAA will soon be repealed. Indeed, with diplomatic relations now re-established, many observers in Cuba and the United States alike are saying that getting rid of the CAA is a prerequisite for truly normal bi-national relations.

In recent years Cubans on the way to the United States have been heading first to Quito, Ecuador and then moving northward to the U. S. border with Mexico. They rely less and less on the once well traveled ocean route across the Florida Straits. Not only are the small boat crossings often deadly, but also the U.S. Coast Guard, on intercepting migrants at sea must, according to a U. S. Cuban agreement of the 1990s, return them to Cuba.

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Speaking to reporters afterwards, Salvadoran foreign minister Hugo Martínez noted general agreement "that the countries meeting here were not responsible for setting off that emigration." He condemned U. S. "measures that discriminate against other immigrants." Costa Rican foreign minister Manuel González cited consensus as to "the inappropriateness of the U. S. Cuban Adjustment Law ... which ... converts the United States into a magnet." Cuban Foreign Minister Bruno Rodriguez, also in attendance, concurred.

More:
http://peoplesworld.org/cubans-stranded-in-costa-rica-blame-falls-on-u-s-cuban-adjustment-act/