The cohort study provided unique opportunities for studying every aspect of the disease and the staff gradually grew to 28 including doctors, medical technologists, nurses, statisticians, computer staff, social workers and counsellors. The 800 children in the Cohort have now been followed for periods up to 48 years, documenting the development of haematological change, principal clinical features and causes of death with the production of 139 papers in the medical literature. Of the 311 subjects with HbSS, 136 have died, 82 emigrated, and 93 are alive and resident in Jamaica, the 100% follow-up after 48 years being testimony to the suitability of Jamaica for long-term studies of disease. The Unit was also fortunate in attracting many visiting workers such as Professor Alan Bird from Moorfields Eye Hospital in London, who for 20 years, led a team of ophthalmologists to document the evolution of retinal disease. Support from the in the US also allowed three studies on the role of laser treatment in eye complications. Other close collaborators included Professor David Weatherall and Professor Douglas Higgs of the Weatherall Institute of Molecular Medicine, Oxford, Dr. George Dover of Johns Hopkins Hospital, Baltimore, and Professor Andreas Kulozik of the University of Heidelberg, Germany. The requirements of the staff and the research programmes now outstripped the facilities inherited from the previous MRC Unit and further developments were needed.
