Dr Margaret (Pearl) Dunlevy was an epidemiologist whose championing of immunisation served to eradicate tuberculosis in Ireland. Born in Donegal, Dunlevy received her licence from RCSI in 1932, coming first in her class. After several years training in Britain, including a period as a TB physician in Cardiff, Dunlevy earned a diploma in public health from UCD, again coming first in her class. She continued her research into TB as assistant medical officer in Dublin, at Crooksling Sanatorium and at St Ultan’s Hospital for Infants, where she was member of the BCG committee (Bacillus Calmette–Guérin: a vaccine primarily used against tuberculosis). The success of a Dunlevy’s BCG pilot programme in Dublin led to its nationwide expansion, with further success. In later years, Dunlevy published extensively and was a columnist for the Irish Medical Times. She was President of the RCSI Biological Society, President of the Irish Society for Medical Officers of Health and a Member and Fellow of the Royal College of Physicians of Ireland.