After reading the article, it seems they need to stop administering the OPV and instead administer the IPV. I can easily see how the OPV can lose it's potency during shipping to different areas. The heat and the cold and other factors like time can create a lot of variables that can affect a live virus. Before reading the article, I thought to myself that they aren't getting the vaccine. After reading the article, I can see that they probably aren't getting a 'good' vaccine. Seems obvious to switch to the IPV.