For decades prior to the 1930s, southern racism and poverty had created an alarming increase in deaths among African Americans due to tuberculosis, pellagra and other illnesses.

By creating alliances with influential white and African-American groups and raising funds, Simkins made a substantial impact on the health of African Americans in South Carolina.

She remained active for many years in the Southern Conference Educational Fund (SCEF), a southwide interracial civil rights organization, working with James Dombrowski and Carl and Anne Braden.

In 1981, she was honored by a coalition of civil rights groups, who established an endowment in her name to provide income for activists working for the causes of the underprivileged.

Hundreds of people attended a memorial service following her death on April 5, 1992, and Judge Matthew J. Perry stated: She probably will be remembered as a woman who challenged everyone.

She challenged the white political leadership of the state to do what was fair and equitable among all people and she challenged black citizens to stand up and demand their rightful place in the state and the nation.Simkins died in Columbia, South Carolina on April 5, 1992, an event recognized by the South Carolina legislature.

Her portrait by Larry Francis Lebby, initiated by legislation sponsored by Representative Alma W. Byrd,[6] hangs in the South Carolina State House.