ahlam1399
04-17-2016, 09:10 PM
155 countries and territories are switching to a different polio vaccine, in what health officials say is the next step to completely eradicating the disease worldwide.
أكثر... (http://www.npr.org/sections/thetwo-way/2016/04/17/474580802/new-polio-vaccine-rolled-out-in-massive-synchronized-worldwide-switch?utm_medium=RSS&utm_campaign=news)
أكثر... (http://www.npr.org/sections/thetwo-way/2016/04/17/474580802/new-polio-vaccine-rolled-out-in-massive-synchronized-worldwide-switch?utm_medium=RSS&utm_campaign=news)