The controller is priced at $50 USD, and will release alongside Valve's Steam Link service, which is also slated for a $50 release. The controller's worldwide pricing will be announced closer to November, Valve said. Hands-on With the Updated Valve Controller. 01:37.
Polio rose to epidemic proportions in the United States with more than 21,000 cases reported in 1952 [3]. With the development of effective vaccines against the virus during the 1950s the incidence of poliomyelitis went in decline and the last case of wild-type virus reported in the United States was in 1979.
Below are three graphs. The first shows the number of polio cases in the United States, adults and children, from 1937 to 2013. The second graph shows the number of deaths caused by the polio virus in adults and children from 1950 to 2013. And the third graph shows the polio vaccination rates among children aged 19 to 36 months in the United States from 1980 to 2014. As of Aug. 18, 2014, the CDC recommends that children receive the first dose of the polio (IPV) vaccination at 2 months of age. Microscopic view of the polio virus