History of poliomyelitis Hospital, successfully cultivated the poliovirus in human tissue. This significant breakthrough ultimately allowed for the development of the polio vaccines. Enders and his colleagues, Thomas H. Weller and Frederick C. Robbins, were recognized for their labors with the Nobel Prize in 1954. Two vaccines are used throughout the world to combat polio. The first was developed by Jonas Salk, first tested in 1952, and announced to the world by Salk on April 12, 1955. The Salk vaccine, or "inactivated poliovirus vaccine" (IPV), consists of an injected dose of killed poliovirus. In 1954, the vaccine was tested for its ability to
Salk of soldiers (fire and maneuver team) forming a fireteam. Salk A salk () is a small military unit led by a senior soldier that is subordinate to an infantry squad. "Salk" is bigger than a lahingpaar ("fire and maneuver team") but smaller than a jagu ("squad"). It is also one of the smallest military formation among the Estonian Ground Force infantry units. It usually consists of three to five soldiers, and may be further subdivided into fire and maneuver teams. A "salk" is composed of two fire and maneuver teams of two soldiers each, as well as a fireteam leader