Poliomyelitis to occur in the late 19th century in Europe and the United States. In the 20th century it became one of the most worrying childhood diseases in these areas. The first polio vaccine was developed in the 1950s by Jonas Salk. In 2013 the World Health Organization hoped that vaccination efforts and early detection of cases would result in global eradication of the disease by 2018. The term "poliomyelitis" is used to identify the disease caused by any of the three serotypes of poliovirus. Two basic patterns of polio infection are described: a minor illness which does not involve the
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