1. Celestino Hernández Robau Hospital, Villa Clara, Cuba.
2. Center of Molecular Immunology, Havana, Cuba.
3. José Ramón López Tabranes Hospital, Matanzas, Cuba.
4. Ramón González Coro Hospital, Havana, Cuba.
5. María Curie Hospital, Camagüey, Cuba.
6. Conrado Benítez Hospital, Santiago de Cuba, Cuba.