this is bbc news: i'm david eades with the latest headlines for viewers in the uk and around the world. a blunt warning from the us vice president on a visit to central america — don't come to the united states because you won't get in. i want to be clear, to the folks in this region who think about making the dangerous trek to the united states—mexico border, do not come. the first new treatment for alzheimer's for nearly twenty years has been approved by us regulators. this will give hope to the people who have not had any hope for a very long time. there are patients and participants in my trials who were desperate to find something that will help. a dramatic fall in applications from asians to study at american universities