Fitch isn't saying that either of those events is imminent but Latin America faces that double whammy if things take a turn for the worse either in the U.S. economy or in China.
This is because Latin American economies have strong links with the U.S. economy even where political links remain virtually non-existent, as in Cuba and Venezuela.
Despite frequent diplomatic or political spats with Cuba and Venezuela, two regional states that are seen to be extreme left of other regional countries judged to be friends, mercantile and oil trade continues between those countries and the United States, independent analysts said in response to the Fitch report.
The Fitch special report said a potential "double-dip" in the United States or a hard landing in China would have negative economic implications for Latin American countries.
"Commodity-exporting countries in the region would see their external accounts deteriorate, although in most cases, external buffers are relatively strong to prevent a currency or a balance-of-payments crisis," Fitch said.
The scale of dislocation would vary across the region contingent on countries' starting economic position, fiscal and external buffers and policy flexibility. Sovereign ratings could suffer in some cases, depending on the depth and duration of the shock and the authorities' policy response. However, neither of these scenarios is Fitch's base case.
"We believe that economies with strong trade links to the U.S. economy, particularly Mexico and the Central American nations, could contract or decelerate sharply if a 'double-dip' occurs in the U.S.," said Fitch expert Santiago Mosquera, a director at the rating company.
If the United States suffered that economic eventuality, he said, demand for Latin America exports would collapse. Given the nature of their export-oriented industries and the spill-over effects to other sectors, domestic demand and employment in those countries could be negatively affected, too.
Fitch says a result of a U.S. slowdown would be a dramatic drop in U.S. tourism to the region and cuts in Latin American family remittances to their native countries.
Fitch cited the smaller economies of Aruba, Costa Rica, the Dominican Republic, Ecuador, El Salvador, Guatemala, and Jamaica among those exposed to the risks. But other, larger economies would not be immune to dangers.
Despite the increase in trade between China and Latin America in recent years, the impact from a potential hard-landing in China could come from its effect on commodity prices.
"Commodity-exporting countries in the region would see their external accounts deteriorate, although in most cases, external buffers are relatively strong to prevent a currency or a balance-of-payments crisis," Mosquera said.
However, countries like Argentina and Venezuela may face increased currency pressures while Ecuador could potentially see a harder economic adjustment due to its dollarized foreign exchange regime.
Adverse terms of trade shock will slow growth dynamics in the region due to the spillover effects on domestic demand and a possible reduction in capital flows.
Some of the more heated economies, in particular Brazil, Argentina and Chile, are already complaining their exports are affected by cash infusions drawn to their interest rates, causing national currencies to overvalue.
Fitch said pressures could build on public finances, particularly where governments show strong dependence in commodity-related revenue, such as Bolivia, Ecuador, Venezuela, and Mexico, or where the economies lack fiscal ability to maneuver in hard times -- Argentina, Brazil, Colombia, Ecuador, Mexico, and Venezuela or in countries that lack large fiscal savings.
The last category is said to include nearly all Latin American countries except Chile and Peru.