I'm very fond of this location because it has a lot meaning in public health. It's part of the history of why we are so much healthier today than we were two hundred years ago if we go back to 1800s, beginning of the eighteen hundreds Denmark was industrializing, just like many other countries and people were moving into the cities to work in the factories, but they moved into what today we'd call sub-conditions, really lousy for their health and health conditions were terrible. But then in 1853 there was a cholera epidemic and 3,000 people died in the space of a few weeks of a total population of 150 thousand or so so it's very dramatic and very tragic and in the aftermath of that, people started to realize that it had something to do living conditions that were there and so you had a group of people, both medical professionals but also the city government and politicians and industrialists as well as the workers themselves who really started being very aware of that and as a result of that people were allowed to build houses outside the city walls. Until then Copenhagen had been a walled city and you were not allowed to build outside the walls but then they realize that really something had to be done you should be able to build outside the walls and so people move out and these were some of the first buildings that were built this was built and this group of houses was built in 1874 and health got much better and one of the things that's interesting to me is that you have all these different people the politicians, the medical professionals, they met up they all agreed that this was an important thing to build these houses and because they build houses that were actually quite modest each of these houses and small houses had three families in them but importantly they also had a pump and a latrine outside and medical profession didn't really... they had a very vague and basically mistaken understanding of what caused cholera or how to treat it but of course when people moved into these houses, as modest as it might have been, the fact that they had access to a latrine and to a pump, meant that health improved dramatically. So this was all before medical knowledge had really advanced that far. (You, being a health demographer,) (could you tell us a bit about the demographic situation.) (For example, the birth rates are falling these years.) (So, will the population actually grow in the future?) As you're saying, this decrease in the birth rate is one is major demographic trend of the last sixty years or so. In 1950, women, on average, were having five children, globally, and today it's less than 2.5 children per woman, globally. So, that is a dramatic change actually. But, of course, the population is still growing, because as long as the women are having more than the so-called replacement level, which is often around 2.1 children per woman the population will grow. Right now it's growing at about eighty million a year. (Will it continue like that?) That, of course, depends on how... what assumptions we make about the future and one of the things that, specific to demography, is that it's quite predictable or that it's relatively predictable. Let me give you a story. When my father turned eighty he said to my mother: "Well, Karen, I made it to eighty." And she said to him, according to what he remembers, she said: "Well, yes, but it sure took you a long time." So, of course, as I say, demography is relatively predictable it takes 80 years to become 80 years old, so demographers are prone to making predictions decades ahead in a way you would never catch an economist doing it. So, indeed you have projections of populations that demographers have made. For example, if you see this graph, today we are on average... rather, the estimate of how many people in the world is 7.4 billion or so. That's today, 7.4 billion. If you project that until 2050, the estimates are about 9.6 billion, what is called the most likely projection. But that, of course, if you protect that further into the future, that depends very much in the assumptions that you make. Again, what is called the most likely projection is that we will have 11 billion people by the end of the century, but that is on the assumption that birth rates continue to decline at the rate they've been declining until now. If, instead, they stay constant in every country in the world, then we will be at 28 billion. So, it's just to show that these projections depend very much on the assumptions that you make and small differences in your assumptions have a very large impact when you make a projection. for, closer to a 100 years. You can see here that the world population in terms of more developed regions and less developed regions and the urban/rural, you can see that the lowest one that is the rural area of the more developed countries, that's small and declining. The urban areas of more developed countries also fairly stable and fairly small but certainly not increasing very much. That's about one billion people. But then if you look at the rural areas of the less developed regions, that's the green one, you can see that that's actually not increasing, that's staying pretty stable and the place where you really have an increase, that's the red one that's the less developed regions, urban areas just about all future growth in the world population will happen in urban areas of less developed regions. And out of those three billion or so,one bilion are presently estimated to live in slum conditions So, if we first look at the age-sex composition, I think it's very important that we remember that each country is quite different on that. here's one from Iran. In 1990, Iran looked like what was sort of classical so-called population pyramid, with many children and then decreasing numbers as you go up with a very high birth rate of about six or so children per woman. And this was partially because the or at least you can say that the government at that point was very much in favor of high birth rates - at the time they were in a war with Iraq and that is often the case during a war you want more children to replenish etc etc. Then in 1990, when the war with iraq was over, the minister of health went to the leadership and said this is not good - six children per woman - This is not good for the health of the mothers, it's not good for the health of the children, it's is not good for the health of the family, it's not good for the economy. We should start a family planning program. And so, indeed family planning program was started, which was one of the most far-reaching ever to be seen, actually. And one of the things he did, for example, was that, you saw that every couple that was getting married had to go for family planning education before they got married. Both the men and the women. Very unusual. And as a result, the birth rate fell, so instead of having six children, women were having two children, approximately. And this happened in 10 years. Very fast. So, you see that these people got older here and then the birth rates starts to decline you have much fewer children. This is in 2010. If you project it into the future, into 2050, these young children here will have got to be young adults here, and will have become older adults here. So you see a child bulge, developing into this bulge, developing into this old age bulge. Now, Iran is a very special case, an extreme case of this, but actually something a little bit in that direction is happening with the rest of the world also. But not in all countries, for example, in the neighboring countries like Afghanistan, this hasn't happened. May be small changes, but otherwise it still looks like the pyramid over here in 1990. So, Afghanistan still looks like this pyramid that Iran was in 1990, 25 years ago. (What about the migration?) Yes that is, of course, also a very important demographic factor. So, here again, democraphers will say that the most important and migration trend is not international migration, it's not displacement. Those are important issues in themselves, but from a democratic point of view, the biggest change is urbanization urbanization within the same country. So, by 2008 or so, Half the world's population was living in urban areas for the first time. Here again you have to look at the age-sex composition because isn't just the whole rural population that is moving into the cities. Here's an example from China, in 2000 and you can see that the people - this is age pyramid of migrants, in time, people who moved to the cities - and you can see that most the people who moved to the cities are young adults, between the ages of 15 and, say, 50 or so. They're the ones who moved into the cities, leaving behind the children and the older adults. So, this of course, has health implications these people have different health needs than generally very healthy young adults, but the health needs they have in health care will be reproductive health, example whereas the children will need vaccinations and older people will need help with non-communicable diseases. So, that's sort of the patterns of health and health care that you need, but equally important is that in most developing countries low and middle-income countries, the people who look after older people are the young adults. So, the young adults have all moved into the city, leaving these older adults in the countryside without that day-to-day care and that's very important in low and middle-income countries family care, where older adults still rely on family for their health care. Now another thing that's important in migration is that recent migrants often move into slum areas. You have less good conditions than those who are long-term residents. Here is just a picture that shows that. This is from Cotonou, in Benin, in West Africa, and you can see that you have some very nice looking at houses up on the hills and that you have some more slum looking house in town close to the water, very close to the water and this is a fairly picture that will see in many places those who're well-established, they will have nice housing those who are recent arrivals will move into areas where the housing is not that good and which is very vulnerable to either slow onsets - rise in sea levels - or sudden onset disasters - hurricanes and things like that. And, in fact, this is just one picture but altogether something like a third of all urban populations live in slums and an increasing proportion of those are living in urban centers which are close to the water. So. you have what is called a low elevation coastal zones. People living in low elevation coastal zones, that's a very common concept within disaster work. And they are, of course, very vulnerable to both slow onset and sudden onset, water-related disasters. And this is actually recognize in the in the new sustainable development goals, which will presumably be adopted in September. The old Millennium Development Goals had a little bit about urban areas, reducing the number of slums, numbers of slum dwellers, etc. But the new sustainable development goals of are, of course very focused on environmental issues and one of the words they will mention again and again is resilience a lot of reference to resilience and there's a whole goal devoted to urban areas and in particular focusing on the resilience of people living in areas like this - slum dwellers living in areas which particularly vulnerable to sudden onset disasters water related, and how one can actually help the coping capacities and the resilience of populations like that.
