91Èȱ¬

In this month's 91Èȱ¬ Health Check with Claudia Hammond and Dr Ayan Panja, we focus on the latest research helping babies and children around the world. Our first destination is Ukraine, which has the lowest childhood vaccination rates in Europe. Could this make the country vulnerable to outbreaks of dangerous diseases such as polio? Irene Caselli reports from Venezuela, where politicians have provoked a row over parental choice in their bid to promote breastfeeding over formula milk. And Claudia finds out why psychologists in London want to know why babies laugh � and what it tells us about the development of their minds.