Cuba is responsible for developing two of only 23 coronavirus vaccines to have entered phase III trials anywhere in the world - and it has another three on the way. Helen Yaffe (University of Glasgow) explains how the Soberana, Abdala, and Mambisa vaccines work;
https://blogs.lse.ac.uk/latamcaribbean/2021/03/31/cubas-five-covid-19-vaccines-the-full-story-on-soberana-01-02-plus-abdala-and-mambisa/
