You may be surprised to see two lectures on death in adolescence in this series. Because we tend to view the adolescent years as the healthiest in life, we tend not to think about death in this age group. Indeed, until very recently, many in health policy would have had a similar view of mortality in young people, that death wasn't common, and was of little policy relevance. With the publication of a number of recent sentinel papers, we now understand there are around 2.5 million deaths in young people aged 10 to 24 each year. And that by and large, these deaths are preventable. It is first, perhaps worthwhile revisiting the idea of a window of vulnerability for health problems related to emotion and emotional control. When we consider mortality in young people, it is largely related to problems of this kind. Before moving to talk about the specifics of mortality in young people, it's important to understand where our information comes from. The best mortality data comes from countries that operate a national death register. Those countries with a national death register capturing at least 70% of all deaths are shown on this slide. One important message is that those countries in Sub-Saharan Africa and Southern Asia, where we know mortality rates in young people are highest, have no national death registers. In those settings, we rely on other methods, other sources of data, such as verbal autopsies used in household surveys. These methods are based on interview, and are far less accurate, particularly when we come to speak about the causes of death. So looking first at where deaths tend to occur in young people, the darker shades reflect higher mortality rates in 10 to 24 year olds. In this slide, the global regions are grouped according to the World Health Organization, with the high income countries grouped separately. You will see that mortality in high income countries is much lower than in any of the other regions. The Western Pacific region is dominated by China, which has comparatively low mortality rates in young people. Other places in the region, including Papua New Guinea and the Pacific Island nations, have much higher mortalities, but this is obscured by the weight of numbers in China. The countries of the former Soviet Union and Latin America have an intermediate mortality pattern. This is illustrated in this next slide by contrasting the very different mortality rates in young males compared to young females in these regions. Perhaps you may have some idea about what is causing death in young males in Latin America. If you guess that it might be something to do with high rates of homicide, you would be right. And in the Russian Federation, here, the high mortality rates in males result from a mixture of homicide, suicide, and motor vehicle injuries. The high mortality rates of Southeast Asia and the Eastern Mediterranean region differ in that rates of death are actually very similar in males and females. Southeast Asia is marked by very high rates of injury deaths in young women compared to other parts of the world. These injuries include deaths due to suicide and burning. But the highest mortality rate region is Sub-Saharan Africa, where mortality rates in young women exceed those in young men. Again, perhaps you might be wondering why this should be. If you thought it was something to do with high maternal mortality, and HIV deaths in young women, you would be correct. If we take a finer grained look at the 21 global sub-regions of the global burden of disease study, the differences in sex ratios of death become clear. The highest mortality regions are in Central, Southern, and Eastern Sub-Saharan Africa. Here, there are generally more deaths in females than in males. Mortality in Western Africa has until recently been a little lower than elsewhere, probably because HIV is less endemic. That pattern will have changed as a result of the recent 2015 Ebola outbreak. Many of the Ebola victims are, in fact, young people. South Asia stands out for its relatively high mortality in young women. Both injury and maternal deaths contribute to this picture. The lowest mortality regions are those with the highest income. In these subregions the great majority of deaths are in males. If we consider the question of where the most deaths occur in adolescents the picture looks somewhat different. This slide illustrates clearly that more deaths in 15 to 19 year olds occur in South Asia than in any other sub-region. This reflects the size of the adolescent population in countries such as India, Pakistan, and Bangladesh. The bubble diagram on the right illustrates this again. Even though Eastern, and Eastern Sub-Saharan Africa has a higher death rate, the size of the bubble in South Asia is much larger, reflecting that much larger number of adolescents in that sub-region. This word cloud illustrates the same point down to country level. India, Pakistan, Nigeria, and China stand out in terms of the numbers of deaths of girls aged 15 to 19 because of their large adolescent populations. Lastly, there is a question of what happens to mortality in young people with economic development. We know that with economic development there have been great improvements in mortality in childhood, and maternal mortality as well. This graph shows all cause mortality trends in 50 predominantly high and middle-income countries with good mortality data going back 50 years. These improvements in early childhood mortality can be seen in one to four year olds, where the reduction in mortality over 50 years has been around 80%. In contrast, the mortality trajectory for young adults and older adolescents is not changed over 50 years in these countries. Indeed, in these countries the mortality in young adulthood is now substantially higher than it is in earlier childhood. This is largely due to our success in controlling childhood infectious diseases through better sanitation, and nutrition, vaccination, and effective treatment. But a failure to make similar progress in adolescents and young adults is now a challenge for the global public health community.