More likely it was smallpox contacted through Basque fishermen who were following the cod runs.
There is some circumstantial evidence that the Basque were aware of some parts of North America due to their wide ranging pursuit of cod.
I actually read a book about cod fishing. Cod used to be extremely plentiful in the North Atlantic until a leftwing Canadian government decided to get in the fish factory business. Despite the fact that their own fishermen begged them not to massively harvest cod from large fish factory boats, the Canadian government went ahead and did so with the result that the cod population of the North Atlantic was almost wiped out and never recovered.
p.s. When I was a kid in Puerto Rico one of my favorite foods from street vendors was Bacalao Frito. Fried salt cod. YUmmie!