via HeritageDaily: 17th- and 18th-century risk of disease through Migration

17th- and 18th-century risk of disease through Migration

HERITAGE March 3, 2014 – No comments
smallpox

The fate of migrants moving to cities in 17th- and 18th-century England demonstrates how a single pathogen could dramatically alter the risks associated with migration and migratory patterns today.

Cities have always been a magnet to migrants. In 2010, a tipping point was reached for the first time when, according to the World Health Organization, the majority of the world’s population lived in cities. By 2050, seven out of 10 people will have been born in – or migrated to – a city. One hundred years ago, that figure was two out of 10.

Today, cities are generally the safest places to live. If you live in one, you’re likely to be richer than someone living in a rural environment. If you’re richer, you’re likely to live longer. If you live in a city, you have better access to hospitals and healthcare, and you’re more likely to be immunised.

But that was not always the case. In 17th- and 18th-century England, city life was lethal – disproportionately so for those migrating from the countryside.

Dr Romola Davenport is studying the effects of migration on the health of those living in London and Manchester from 1750 to 1850, with a particular focus on the lethality of smallpox – the single most deadly disease in 18th-century England. In the century before 1750, England’s population had failed to grow. Cities and towns sucked in tens of thousands of migratory men, women and children – then killed them. It’s estimated that half of the natural growth of the English population was consumed by London deaths during this period. Burials often outstripped baptisms.

In 2013, cities are no longer the death traps they once were, even accounting for the millions of migrants who live in poor, often slum-like conditions. But will cities always be better places to live? What could eliminate the ‘urban advantage’ and what might the future of our cities look like if antibiotics stop working?

By looking at the past – and trying to make sense of the sudden, vast improvement in survival rates after 1750 – Davenport and the University of Newcastle’s Professor Jeremy Boulton hope to understand more about city life and mortality.

“For modern migrants to urban areas there is no necessary trade-off of health for wealth,” said Davenport. “Historically, however, migrants often took substantial risks in moving from rural to urban areas because cities were characterised by substantially higher death rates than rural areas, and wealth appears to have conferred little survival advantage.”

The intensity of the infectious disease environment overwhelmed any advantages of the wealthy – such as better housing, food and heating. Although cities and towns offered unparalleled economic opportunities for migrants, wealth could not compensate for the higher health risks exacted by urban living.

“Urban populations are large and dense, which facilitates the transmission of infectious diseases from person to person or via animals or sewage. Towns functioned as trading posts not only for ideas and goods but also for pathogens. Therefore, growing an urban population relied upon substantial immigration from rural areas,” explained Davenport.

“After 1750, cities no longer functioned as ‘demographic sinks’ because there was a rapid improvement in urban mortality rates in Britain. By the mid-19th century, even the most notorious industrial cities such as Liverpool and Manchester were capable of a natural increase, with the number of births exceeding deaths.”

Davenport has been studying the processes of urban mortality improvement and changing migrant risks using extremely rich source material from the large London parish of St Martin-in-the-Fields. The research, funded by the Wellcome Trust and the Economic and Social Research Council, is now being augmented with abundant demographic archives from Manchester, funded by the Leverhulme Trust.

For both cities, Davenport and colleagues have access to detailed records of the individual burials underlying the Bills of Mortality, which were the main source of urban mortality statistics from the 17th to the 18th century. These give age at death, cause of death, street address and the fee paid for burial, which enables them to study the age and sex distribution of deaths by disease. In addition, baptismal data allow them to ‘reconstitute’ families as well as to measure the mortality rates of infants by social status.

“The records themselves give only a bald account of death,” said Davenport. “But sometimes we can link them to workhouse records and personal accounts, especially among the migrant poor, which really bring home the realities of life and death in early modern London.

“Smallpox was deadly. At its height, it accounted for 10% of all burials in London and an astonishing 20% in Manchester. Children were worst affected, but 20% of London’s smallpox victims were adults – likely to be migrants who had never been exposed to, and survived, the disease in childhood. However in Manchester – a town that grew from 20,000 to 250,000 in a century – 95% of smallpox burials were children in the mid-18th century, implying a high level of endemicity not only in Manchester but also in the rural areas that supplied migrants to the city.

“So studying urban populations can tell us not only about conditions in cities but also about the circulation of diseases in the rest of the population.”

The greater lethality of smallpox in Manchester is, for the moment, still a mystery to researchers; but evidence suggests the potential importance of transmission via clothing or other means – as opposed to the person-to-person transmission assumed in mathematical models of smallpox transmission in bioterrorism scenarios. Although smallpox was eradicated in the late 1970s, both the USA and Russia have stockpiles of the virus – which has led to fears of their use by terrorists should the virus ever fall into the wrong hands. Data on smallpox epidemics before the introduction of vaccination in the late 1790s are very valuable to bioterrorism researchers because they provide insights into how the virus might spread in an unvaccinated population (only a small proportion of the world’s population is vaccinated against smallpox).

From 1770 onwards, there was a rapid decline in adult smallpox victims in both London and Manchester, which Davenport believes could be attributable to a rapid upsurge in the use of smallpox inoculation (a precursor of vaccination) by would-be migrants or a change in the transmissibility and potency of the disease. By the mid-19th century, towns and cities appear to have been relatively healthy destinations for young adult migrants, although still deadly for children.

“Smallpox was probably the major cause of the peculiar lethality of even small urban settlements in the 17th and 18th centuries,” said Davenport, “and this highlights how a single pathogen, like plague or HIV, can dramatically alter the risks associated with migration and migratory patterns.”

“The close relationship between wealth and health that explains much of the current ‘urban advantage’ is not a constant but emerged in England in the 19th century,” added Davenport. “While wealth can now buy better access to medical treatment, as well as better food and housing, it remains an open question as to whether this relationship will persist indefinitely in the face of emerging threats such as microbial drug resistance.”

Header Image : An 1802 cartoon of the early controversy surrounding Edward Jenner’s vaccination theory, showing using hiscowpox-derived smallpox vaccine causing cattle to emerge from patients. WikiPedia

Contributing Source : University of Cambridge

© Copyright 2014 HeritageDaily – Heritage & Archaeology News

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via GoogleMapsMania: Google’s Population Explorer-TRY THIS!

Monday, February 24, 2014

Population Mapping


Population Explorer is a Google Maps based tool that can estimate the population of any area on Earth, down to an area of 1km2.

Draw a polygon anywhere on the Earth and Population Explorer will provide an estimate of the population within the defined area. I’ve tested the tool by selecting areas that I know, such as London and the UK, and I’ve also tested it by searching for estimates in deserts and the sea. From my limited testing Population Explorer does seem to return accurate population estimates.

The results of each search displays the total population, the population density, the number of males & females, the age structure of the population and population growth estimates.

Map via WashingtonPost: Where people are moving to and from

Where people are moving to and from

The map above comes from Atlas Van Lines and shows where their customers were headed last year. Most states had a steady balance of people coming and going, but the blue ones below are where the movement was mostly inbound and the yellow ones show states that were losing people faster than they were gaining them.

via PewResearch: Global Population Estimates by Age, 1950-2050-INTERACTIVE

JANUARY 30, 2014

Global Population Estimates by Age, 1950-2050

Pew Global Population Interactive

The demographic future for the U.S. and the world looks very different than the recent past. Growth from 1950 to 2010 was rapid—the global population nearly tripled, and the U.S. population doubled. However, population growth from 2010 to 2050 is projected to be significantly slower and is expected to tilt strongly to the oldest age groups, both globally and in the U.S.

Source: United Nations, Department of Economic and Social Affairs, World Population Prospects: 2012 Revision, June 2013

via Nat’l Geographic: The Growth of Megacities

Geography in the News: The Growth of Megacities

Posted by Neal Lineback of Geography in the NewsTM on February 17, 2014
By Neal Lineback and Mandy Lineback Gritzner,  Geography in the NewsTM

Megacities’ Expansive Growth

For the first time in human history, more of the world’s 6.8 billion people live in cities than in rural areas. That is an incredible demographic and geographic shift since 1950 when only 30 percent of the world’s 2.5 billion inhabitants lived in urban environments.

The world’s largest cities, particularly in developing countries, are growing at phenomenal rates. As a growing landless class is attracted by urban opportunities, meager as they might be, these cities’ populations are ballooning to incredible numbers.

A May 2010 Christian Science Monitor article on “megacities” predicted that by 2050, almost 70 percent of the world’s estimated 10 billion people—more than the number of people living today—will reside in urban areas. The social, economic and environmental problems associated with a predominantly urbanized population are considerably different from those of the mostly rural world population of the past.

A megacity is an urban agglomeration (accumulation) with more than 10 million inhabitants. Sixty years ago in 1950, there were only two megacities—New York-Newark and Tokyo. In 1995, 14 megacities existed. Today, there are 22, mostly in the developing countries of Asia, Africa and Latin America. By 2025, there will probably be 30 or more.

gitn_1049_Megacities

Urbanization has been occurring in the developed countries of the West for 200 years. Since the Industrial Revolution, a period from the 18th to 19th century in which machine-based manufacturing grew tremendously, cities have grown rapidly. As technological innovations flourished, economies previously dependent on manual labor and draft-animals began to change. People moved into the cities to find work and relatively quickly, cities began to grow exponentially.

Today, the most rapid megacity growth is occurring in the world’s least developed and poorest countries—those least able to handle the political, social, economic and environmental problems associated with rapid urbanization.

In the most modern industrialized countries, on average, three out of four people already live within an urban area. In contrast, in the least-developed regions of the world, more than two out of three people still reside in a rural area. But that statistic is changing rapidly.

For people in developing countries, even the slums of cities like Mumbai, India, can offer more opportunities than their poor subsistence-based villages can. People gravitate to the cities because the potential for making money is greater there. While most of the economies in rural areas are agriculture-based with little cash flow, in the cities, people may be able to earn cash for work or retail sales.

The 10 largest cities in the world in 2010 and their projected populations by year 2025 are Tokyo, Japan  (37.1 million), Delhi, India (28.6), São Paulo, Brazil (21.7), Mumbai, India (25.8), Mexico City (20.7), New York-Newark (20.6), Shanghai, China (20.0), Calcutta, India (20.1), Dhaka, Bangladesh (20.9) and Karachi, Pakistan (18.7).

According to the Christian Science Monitor, along with the masses come problems associated with providing necessary services like clean water, sanitation systems to remove the megatons of garbage and human waste and transportation systems to ferry workers. In addition, many cities have difficult times providing electrical networks, health care facilities and police protection.

Urbanization is not all bad news. According to the Christian Science Monitor, some see great promise in the trend, especially those companies that build roads and buildings.  If a city is efficient, energy consumption can decrease by 20 percent. Transportation costs for goods and labor can fall considerably in cities because markets and workers are all close together. In essence, cities are where cash flows—they are where economic growth takes place.

As the world’s population increases at the rate of 134 million per year, the urbanization process is pushing more and more people into the cities. Such frenetic rates of urbanization and intense poverty of large urban populations strain resources. Nonetheless, to poverty-stricken, landless people, cities offer visions of opportunity. The resulting massive urban underclass, particularly in developing countries, represents one of the world’s greatest social and economic challenges.

The real question is, “What are the limits to urban growth?”

And that is Geography in the News.

Sources: GITN #1049, “Growing Megacities,” June 28, 2010; GITN #844, “Megacities: 10 Million or More People,” Aug. 4, 2006; and Bruinius, Harry, “March of the Megacities,” The Christian Science Monitor, May 10, 2010.

Co-authors are Neal Lineback, Appalachian State University Professor Emeritus of Geography, and Geographer Mandy Lineback Gritzner. University News Director Jane Nicholson serves as technical editor. Geography in the NewsTM  is solely owned and operated by Neal Lineback for the purpose of providing geographic education to readers worldwide.

via the Guardian: Time running out for China’s one-child policy after three decades

Time running out for China’s one-child policy after three decades

As list of exemptions grows, experts predict scrapping of rule said to have prevented 400m birthsChina baby
Even if the one-child policy is scrapped, many Chinese couples say they are unlikely to have bigger families because of the expense. Photograph: Afp/AFP/Getty Images

Chen Xi once saw the one-child policy as a brick wall, unyielding and inevitable. Now she considers it a nuisance.

The turning point came in November when, just as she began the fifth month of her pregnancy, Beijing announced a big change to the contentious policy, allowing couples to have two children if one parent is an only child. Chen, a 28-year-old employee at a state-owned enterprise, should qualify – her husband does have siblings, but she does not.

Yet her hopes may be dashed: although she is pregnant with her first child, she lives with her husband’s 16-year-old daughter from a previous marriage, and family planning officials may consider the teenager her own.

As Chen fruitlessly searched the internet for details, her emotions turned from hope, to confusion, to anger – first at the lack of information, then at the policy as a whole. “This policy has so many downsides – it violates natural law, it makes kids spoilt and thankless,” she said. “Sooner or later, they’re going to have to give it up. It’s really just a matter of time.”

Chen is not alone. While experts doubt the relaxation will deliver a baby boom, they say it has delivered something else entirely: a paradigm shift for many Chinese people who, over three decades, have grown numb to the government’s role in their reproductive affairs.

The policy’s pitfalls are common knowledge: it has engendered an economically perilous demographic crunch and human rights abuses such as forced late-term abortions, abducted infants and the use of violence to collect fines.

Yet “resistance against the policy has never really been that strong”, said Wang Feng, an expert on China’s demographics at the University of California, Irvine. “That’s why I think this top-down change – when the government says ‘now the policy has outlived its use and needs to be changed’ – that actually triggers a change in thinking.”

Five years ago, Wang estimated, only three out of 10 Chinese people were adamant that the policy should be scrapped. “Now, with the announcement of this change, it may not be an exaggeration to see a shift to the other way around. Maybe nine out of 10 would say it’s about time to get rid of this.”

Last week, the wealthy coastal province of Zhejiang became the first to sign the revision into law. Hubei in central China and Guangxi in the south could follow suit by March, state media say.

Authorities say the policy has prevented 400m births since its implementation in the late 1970s. For evidence, they often point to UN estimates that the country’s birthrate has dropped from 4.77 births per woman in the 1970s to 1.64 in 2011. Yet experts have called the figure into question. China’s greatest fertility drop-off occurred in the decade before the policy was introduced, they say; its continuing decline mirrors that of other developing nations.

China already allows many people to have two children, such as couples who are both only children, and ethnic minorities.

Yet many of these families refrain, unwilling to bear the economic cost of a second child. Since the early 1990s, “there’s been no tightening up of the policy, but the fertility rate continues to decline”, said Zuo Xuejin, an executive vice-president at the Shanghai Academy of Social Sciences. “So the basic driver for declined fertility is socioeconomic change.”

If China’s demographic trends hold, the country will probably scrap the policy by 2020, according to Zuo. “By 2025, the government will be encouraging people to have more children.”

Yet the policy will almost certainly continue to have a hold on people for years, experts say, for reasons that have little to do with demographics. For leading officials, backtracking on a three-decade-old policy would entail an intolerable loss of face. The country’s sprawling family planning bureaucracy, which levies more than £1bn annually in fines, is too deeply entrenched to suddenly dismantle.

“At the same time as China announces this policy change, it says the government will continue to put population control as its main mission,” said Cai Yong, a sociology professor at the University of North Carolina, Chapel Hill. “You see a contradiction right there.”

Chen is still waiting for details on her eligibility, and probably won’t find answers until Beijing formally legislates. She badly wants a second child, unlike many of her colleagues. “If my child doesn’t have any siblings, she’ll grow up very lonely,” she said. If she finds out it is illegal, she will book a flight to the US and hopefully give birth there, granting her child foreign citizenship.

“Before, most people would go to Canada, but some policies changed, so people don’t go there any more,” she said. “Going to America is really popular. If that’s what it takes, that’s what I’ll do.”

via APA: UN: There are 232 million international migrants worldwide

Years later, we still see evidence that Earnst Ravenstein’s Laws of Migration are still at work.
-The Human Imprint
▇ ▅ █ ▅ ▇ ▂ ▃ ▁ ▁ ▅ ▃ ▅ ▅ ▄ ▅ ▇
Ravenstein’s Laws of Migration
  1. Most migrants move only a short distance.
  2. There is a process of absorption, whereby people immediately surrounding a rapidly growing town move into it and the gaps they leave are filled by migrants from more distant areas, and so on until the attractive force [pull factors] is spent.
  3. There is a process of dispersion, which is the inverse of absorption.
  4. Each migration flow produces a compensating counter-flow.
  5. Long-distance migrants go to one of the great centers of commerce and industry.
  6. Natives of towns are less migratory than those from rural areas.
  7. Females are more migratory than males over short distances; likewise males are more migratory than females over longer distances.
  8. Economic factors are the main cause of migration.
▇ ▅ █ ▅ ▇ ▂ ▃ ▁ ▁ ▅ ▃ ▅ ▅ ▄ ▅ ▇
 [ 15 February 2014 18:49 ]

Baku. Shamil Alibayli – APA. A new report launched today by the United Nations spotlights the significant impact of young migrants on origin, transit and destination countries and communities, as well as the challenges they face, as told in their own voices.
APA reports quoting UN website that according to the latest UN estimates, there are 232 million international migrants worldwide, representing 3.2 per cent of the world’s total population of 7.2 billion.

There are 35 million global migrants under the age of 20, up from 31 million in 2000, and another 40 million between the ages of 20 and 29. Together, they account for more than 30 per cent of all migrants. Females account for approximately half of all global youth migrants.

Published by the UN Department of Economic and Social Affairs (DESA), the latest World Youth Report outlines the global situation of young migrants by highlighting some of the concerns, challenges and successes experienced by young migrants.

“Recognizing the diversity of youth migrants is important for understanding the impact of migration on the human development of young men and women as well as on their countries of origin and destination,” states the report.

“It is also essential for designing specific interventions that address their unique vulnerabilities and enable them to realize their hopes and aspirations.”

According to the report, the impacts of youth migration are mixed. When young people migrate, they tend to improve both their own financial situation and the economic circumstances of their families through the income they earn and the remittances they send home, while destination countries benefit from greater economic efficiency.

However, countries of origin can suffer from negative impacts of human capital flight, or brain drain, notably of health and education professionals, the report states.

It goes on to say that the process of migration itself brings different challenges and experiences and can affect overall outcomes for young people. Prior to migration, young people may be excited at the prospect of leaving home and discovering a new place, while they also face challenges.

Interactive: Racial Dot Maps via: University of Va.

The Racial Dot Map

One Dot Per Person for the Entire United States

Created by Dustin Cable, July 2013

Access and Use Policy


Link to Full Screen Map

Download a High Resolution Image of the U.S. Racial Dot Map (33 MB)

Please read the Access and Use Policy, which describes how this map can be used and how it should be cited.

NEW: You can see the new Congressional Dot Map project with election results here.

The Map

This map is an American snapshot; it provides an accessible visualization of geographic distribution, population density, and racial diversity of the American people in every neighborhood in the entire country. The map displays 308,745,538 dots, one for each person residing in the United States at the location they were counted during the 2010 Census. Each dot is color-coded by the individual’s race and ethnicity. The map is presented in both black and white and full color versions. In the color version, each dot is color-coded by race.

All of the data displayed on the map are from the U.S. Census Bureau’s 2010 Summary File 1 dataset made publicly available through the National Historical Geographic Information System. The data is based on the “census block,” the smallest area of geography for which data is collected (roughly equivalent to a city block in an urban area).

The map was created by Dustin Cable, a former demographic researcher at the University of Virginia’s Weldon Cooper Center for Public Service. Brandon Martin-Anderson from the MIT Media Lab deserves credit for the original inspiration for the project. This map builds on his work by adding the Census Bureau’s racial data, and by correcting for mapping errors.

The Dots

Each of the 308 million dots are smaller than a pixel on your computer screen at most zoom levels. Therefore, the “smudges” you see at the national and regional levels are actually aggregations of many individual dots. The dots themselves are only resolvable at the city and neighborhood zoom levels.

Each dot on the map is also color-coded by race and ethnicity. Whites are coded as blue; African-Americans, green; Asians, red; Hispanics, orange; and all other racial categories are coded as brown.

Shades of Purple, Teal, and Other Colors

Since dots are smaller than one pixel at most zoom levels, colors are assigned to a pixel depending on the number of colored dots within that pixel. For example, if a pixel contains a number of White (blue dots) and Asian (red dots) residents, the pixel will be colored a particular shade of purple according to the proportion of each within that pixel.

Different shades of purple, teal, and other colors can therefore be a measure of racial integration in a particular area. However, a place that may seem racially integrated at wider zoom levels may obscure racial segregation at the city or neighborhood level.

Take the Minneapolis-St. Paul metro area as an example:

While Minneapolis and St. Paul may appear purple and racially integrated when zoomed out at the state level, a closer look reveals a greater degree of segregation between different neighborhoods in both cities. While some areas remain relatively integrated, there are clear delineations between Asian, black, and white neighborhoods.

Lightly Populated Areas

Toggling between color-coded and non-color-coded map views in lightly populated areas provides more contrast to see differences in population density. Take North and South Dakota as illustrative examples:

In the black and white version, it is easier to see the smaller towns and low-density areas than in the color-coded version. Different monitor settings and configurations may make it harder or easier to see color variations in lightly populated areas, but the non-color-coded map should always show differences in population density fairly well.

Dots Located in Parks, Cemeteries, and Lakes

The locations of the dots do not represent actual addresses. The most detailed geographic identifier in Census Bureau data is the census block. Individual dots are randomly located within a particular census block to match aggregate population totals for that block. As a result, dots in some census blocks may be located in the middle of parks, cemeteries, lakes, or other clearly non-residential areas within that census block. No greater geographic resolution for the 2010 Census data is publicly available (and for good reason).

A more accurate portrayal of the geographic distribution of residents is possible if data is available on the location of parks, buildings, and/or physical addresses. Individual dots could therefore be conditionally placed based on this data.

The following is an example of using additional data to improve the dot density map for the City of Charlottesville, Virginia:

No Extra Data

Using Additional Address and Park Data

By conditioning the location of dots based on physical address and excluding locations with parks or commercial property, the dot map for Charlottesville becomes a more accurate portrayal of the population distribution of the city. However, the City of Charlottesville is unusual in that this data is made publicly available. There are no nationwide datasets for all parks or physical addresses. As a result, the national-level Racial Dot Map does not make these adjustments.

The Data

All of the data displayed on the map are from the 2010 Summary File 1 (SF1) tables from the U.S. Census Bureau. Table P5, “Hispanic or Latino Origin by Race,” was merged with block-level state shapefiles from the National Historical Geographic Information System. Five racial categories were created based on the data in table P5: non-Hispanic White, non-Hispanic Black, non-Hispanic Asian, Hispanic or Latino, and a category for all other racial categories including the multiracial identifications. The sum of all five categories equals the total population.

Methodology

Python was used to read the 50 state and District of Columbia shapefiles (with the merged SF1 data). The GDAL and Shapely libraries were used to read the data and create the point objects. The code retrieves the population data for each census block, creates the appropriate number of geographic points randomly distributed within each census block, and outputs the point information to a database file. The resulting file has x-y coordinates for each point, a quadkey reference to the Google Maps tile system, and a categorical variable for race. The final database file has 308,745,538 observations and is about 21 GB in size. The processing time was about five hours for the entire nation.

The database file was then sorted by quadkey and converted to a .csv format. SAS was able to do this within an hour without crashing.

Processing 2.0.1 for 64-bit Windows was used to create the map tiles. The Java code reads each point from the .csv file and plots a dot on a 512×512 .png map tile using the quadkey reference and x-y coordinates. The racial categorical variable is used to color-code each plotted dot. This process used the default JAVA2D renderer, but other platforms may work better using P2D. Map tiles were created for Google Maps’ zoom levels 4 through 13 to make the final map. A non-color-coded map was also produced to help add more contrast for lightly populated areas. In total, the color-coded and non-color-coded maps contain 1.2 million .png files totaling about 7 GB. Producing all of the map tiles in Processing took about 16 hours for the two maps.

The Google Maps API is used to display the map tiles. Map tiles with zero population are never created using the above method. Therefore, an index was used to tell the map application whether a tile exists in order to prevent 404 errors.

The entire code is up on GitHub and was adapted from code developed by Brandon Martin-Anderson and Peter Richardson in order to account for the racial coding and errors in reading the shapefiles.

via Pew Research Center: As the population grays, Americans stay upbeat

As the population grays, Americans stay upbeat

BY RAKESH KOCHHARLEAVE A COMMENT

FT_14.02.10_USGlobalAging_200pxOne-in-five Americans are expected to be 65 and older by mid-century, and this could be a problem for the country. There is worry that government and household finances may be pushed to the brink by rising pension and health care expenditures. Economic growth, we are warned, might suffer with fewer workers and more retirees. But what does the public think?

It may come as a surprise that the American public is pretty optimistic. In a Pew Research Center survey, only about one-in-four Americans say the growing number of older people is a major problem for the country, nearly two-thirds are confident they will have an adequate standard of living in their old age, and almost one-half say that individuals are primarily responsible for their own economic well-being as they get older.

FT_14.02.10_USGlobalAging_310pxThese opinions differ sharply from public opinion in most of the 20 other countries that we surveyed. Americans are among the least likely to view aging as a major problem; they are more confident than most of their old-age economic well-being; and they are one of few to express in plurality that individuals are primarily responsible for their own well-being in old age.

Why are Americans so confident? And is there a gap between demographic reality and U.S. public opinion? It is hard to be sure, but the views of the American public are consistent with demographic projections. On two major counts—population growth and population aging—the future for the U.S. is robust compared with other countries.

Take population growth. Yes, the U.S. population is expected to grow more slowly in the future—at 0.6% annually from 2010 to 2050 compared with 1.1% annually from 1950 to 2010. But this still amounts to an addition of 89 million people, among the largest gains globally. And the U.S. population should grow much faster than the populations of its major partners (or rivals), such as Germany, Britain, Japan, South Korea and China.

Americans may have another reason to feel more confident than others about their demographic future: the U.S. is aging at a comparatively slow pace. The median age in the U.S. is expected to increase from 37 in 2010 to 41 in 2050. Meanwhile, a greater increaseis expected globally, from 29 to 36, and most people in South Korea, Japan and Germany are expected to be older than 50 by mid-century.

But the U.S. population is still aging, right? Does that raise no concerns?

It is possible the public has heard the alarm bell but believes that corrections will be made. Although it is difficult to anticipate the choices individuals might make in the future, Americans may plan to boost their retirement savings. And family structures may be evolving to adapt to the needs of the elderly, perhaps through growing numbers ofmulti-generational households.

The future state of public expenditures also need not be gloomy. The principal driver of health care expenditures is cost inflation and reining that would significantly brighten the long-run outlook for Medicare and Medicaid. The Congressional Budget Office has alsoestimated that gradually raising the full retirement age for Social Security to 70 for people born in 1973 or later (it is currently at 67 for people born in 1960 or later) would reduce federal outlays on the program.

When it comes to the workforce, the elderly are already showing signs of greater activity. The labor force participation rate among those 65 and older has nearly doubled since 1985. With people living longer and healthier lives, we may continue to see more elderly workers choosing to delay retirement in the coming decades.

Economists have also noted that modest gains in productivity, through innovation, capital investment or a more educated workforce, may counter the effects of an aging workforce. Immigration may also be used to boost the size of the workforce.

All this is not to say that population aging presents no challenges. A recent report from the National Academy of Sciences posits that “Population aging will have profound fiscal effects as well as effects on the broader economy.” But the same study concludes that “[aging does not present]…insurmountable challenges for the United States…An aging society need not have lower living standards, slower growth in innovation and productivity, or inefficiently high tax rates.” The American public, for now, is a believer in the positive.