This is pretty exciting news. Cuba has a long history of sending medical aid to other developing countries, and right now the vaccine timeline for a lot of poor African countries is really, really bad. If this pans out, it could save a lot of lives.
Does Cuba have the capacity to produce enough vaccines for those nations? That would be really surpising to me
The South African government at the time was rabidly anti-communist -- think Eugene McCarthy and the red scare in the U.S. -- so I doubt they would have much to do with Cuba.
And then the apartheid croaked everywhere south of 17th parallel
Beyond that, this vaccine is insanely easier to produce than the mRNA vaccines.