History
Agent Peggy Carter of the SSR went on a mission to the Zodiac base, she took out the Zodiac members single handed and was able to retrieve the serum/virus.[1] The virus became the possession of S.H.I.E.L.D. following its transition from the SSR.
Decades later, the virus was stolen by a terrorist group led by Baker after the organization had labeled the virus as having been destroyed.
S.H.I.E.L.D. agents Captain America; Brock Rumlow and Black Widow managed to retrieve it before it could be used for any purpose.[2]