Hannah Cohen graduated, way back in 1972, from New England Deaconess Hospital School of Nursing in Boston . She has worked in a variety of areas form pediatrics to geriatrics, in hospitals and home care, and in several states and provinces.

She was educated in HIV as a volunteer at the AIDS Committee of Ottawa in 1988 and subsequently was a founding member of Women and HIV projects in Ottawa and Victoria. In 1996, she became the first nurse at Oasis , a program to address gaps in HIV prevention and treatment, especially for people marginalised by poverty, addictions, multiple diagnoses, gender, race or sexuality.

That is also when she joined CANAC/ACIIS. She became the Ontario rep in November, 2002.