Jonas Salk when the Salk vaccine was introduced, polio was considered one of the most frightening public health problems in the world. In the postwar United States, annual epidemics were increasingly devastating. The 1952 U.S. epidemic was the worst outbreak in the nation's history. Of nearly 58,000 cases reported that year, 3,145 people died and 21,269 were left with mild to disabling paralysis, with most of its victims being children. The "public reaction was to a plague", said historian William L. O'Neill. "Citizens of urban areas were to be terrified every summer when this frightful visitor returned." According to a 2009 PBS
Salk "salk" is meant to operate on a battlefield along with other "salk's" on a landscale not greater than 50 x 100 metres. There are no logistical support elements in the structure of a "jagu". In the Canadian Army 'fireteam' refers to two soldiers paired for fire and movement. Two fireteams form an 'assault group' and two assault groups form a section of eight soldiers. Many other armed forces see the squad as the smallest military unit; some countries' armies have a pair consisting of two soldiers as the smallest military unit. In others a fireteam is composed of two pairs