If a person has a disease or condition that prevents the body from making enough healthy blood cells, they may need a blood stem cell transplant. These diseases include: leukaemia, lymphoma, thalassemia, aplastic anaemia, sickle cell anaemia, severe combined immunodeficiency syndrome, myelodysplastic syndromes, congenital neutropenia and chronic granulomatous disease. #WorldBoneMarrowDonorDay