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Our World — 12 July 2008

MUSIC: "Our World" theme

This week on "Our World" ... A changing China challenges its health care system ... a new source for biofuels ... and Florida's planned buy-out of sugarcane farmers offers hope for a threatened ecosystem ...

KRAUS: "This land purchase is going to allow us to restore the Everglades more quickly, in a much less engineered fashion, and in a much more sustainable way."

Saving the Everglades ... how clean hands at childbirth boost infant survival ... and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

We begin today with the world's two most populous countries — China and India — which face challenges as their economies prosper and their populations age.

DENTZER: "These are youthful and vibrant countries in many respects, but they too have aging populations. They are also disturbingly eating more and more like us in the West, and suffering the dietary and health consequences of obesity and other chronic diseases in greater and greater numbers."

Susan Dentzer edits Health Affairs, a journal whose new issue takes a broad look at health policy and practice in China and India.

One article looks at the role of nutrition in China, and wonders if changes in dietary habits will overwhelm the country's health care system.

The author, Barry Popkin, is a professor of nutrition at the University of North Carolina. He has been studying Chinese eating patterns for a decade, conducting in-home surveys in more than 5,000 households, measuring portions and doing medical exams of residents. He says people in China eat differently now than they used to.

POPKIN: "The Chinese consume around three to four times the amount of cooking oil they did several decades ago, and almost consume 400 calories a day from cooking oil. They've shifted from steaming and boiling their food to frying it."

Popkin says another big change is the addition of animal products — mostly dairy, poultry and pork — to their diet.

Those changes in diet and plus a decrease in daily physical activity for many Chinese people are taking their toll. Nearly 30 percent of the population is either overweight or obese, and that percentage is increasing at an alarming rate.

POPKIN: "This would not be important if they were just getting a little fatter. But what's happening is that the hypertension, the diabetes, and all the other heart diseases and cancers are going up very rapidly. So these changes that we're seeing in the way the Chinese are becoming overweight are truly having broader effects on their health and on their well-being."

So China faces new medical challenges with an aging population subject to chronic illnesses and diseases that typically strike beginning in middle age.

China was once known for its rural health workers, so-called "barefoot doctors," who provided basic medical care in the countryside. In the 1970s, the government sharply curtailed public healthcare, but is now moving rapidly to implement insurance programs.

Somnath Chatterji of the World Bank says changes in China are coming at breathtaking speed. Take one statistic - the doubling of the percentage of the population over age 60.

CHATTERJI: "It took France a century to do that. And that has taken China, or will take China, 27 years."

Chatterji writes in Health Affairs about aging populations in China and India. By 2030, older Indians will bear almost half the disease burden in their country. In China, it will be two-thirds. Part of the reason is that smoking continues to be popular in both nations.

Chatterji points out that a key element in a health system is prevention education.

CHATTERJI: "So in other words, if you educate people, and if you empower people to take their own health in their hands, there are chances that actually you'd be able to prevent a lot of this chronic illness. But the time to act is now, not wait for four decades and then suddenly have this sort of come upon you."

China and India both face serious HIV/AIDS epidemics — an estimated 700,000 infected people in China, and two and a half million in India. World Bank public health specialist Kees Kostermans says that in India, officials are using what experts call "evidence-based" prevention strategies - in other words, those which research has shown to be effective.

KOSTERMANS: "Condom promotion, if you focus it on the right groups. If you treat the sexually-transmitted infections. If you make sure that clean needles are available for the injecting drug users. That you use peer education and you involve these high-risk groups themselves in the mobilization for the fight against HIV — all show that you can reduce the risk for HIV transmission, really works."

In China, the government insists it is committed to providing adequate health care for all. Princeton University's Tsung-Mei Cheng interviewed Chinese health minister Chen Zhu for Health Affairs and summarized his comments for reporters.

CHENG: "The government views health care as a right. And it is an ultimate objective of social and economic development in China. But then also they view the right to health care as a means to achieving sustained, coordinated, overall, social and economic development."

In that interview, incidentally, Minister Chen stressed that the government intends to continue giving Chinese traditional medicine equal status in the health care system with modern Western medicine.

As we just heard, some countries moving up into middle-income status have already made big gains in reducing infant mortality. But some of the world's poorest countries are still suffering high death rates at birth and in the first year of life. As we hear from health reporter Rose Hoban, sometimes the simplest changes can make a huge differece.

HOBAN: In the past 20 to 30 years, health experts have done a lot to reduce childhood mortality in developing countries. Low-tech advances such as oral rehydration solution, vaccination campaigns, and nutrition programs have saved the lives of many young children who might have otherwise died.

But in some countries, rates of neonatal deaths remain high. Professor James Tielsch from the Johns Hopkins School of Public Health says part of the problem is that babies are being born at home.

TIELSCH: "So these are not kids that are getting delivered in hospitals or any place like that. They are coming in to life in a very hygiene challenged environment, if you will. quite dirty environments. So there is lots of opportunity for infection."

HOBAN: Tielsch and his colleagues have been following the health of children in an impoverished area of southern Nepal. He says many newborns don't live long enough to benefit from advances in health care. They die of infections within weeks of birth.

So Tielsch's colleagues undertook a campaign to educate tens of thousands of women about a simple health precaution - washing their hands before helping a mother give birth.

TIELSCH: "So we had about 60 percent of the women who actually delivered the babies — whether it's a family member, the grandmother, or whether it's a local untrained traditional birth attendant- who actually wash their hands with soap and water before they deliver the child. And that simple act is associated with an almost 20 percent reduction in death in the first month of life."

HOBAN: The team also taught mothers to wash their hands regularly with soap and water before handling their newborns, such as when they picked them up to breast feed or dress them.

TIELSCH: "That again was associated with a very significant — somewhere in the range of 40 percent — reduction in mortality as well. So these two very simple kind of hygiene-related, hand-washing related behaviors were associated with very large reduction in mortality."

HOBAN: Tielsch says educating women about hand-washing is part of a new campaign to teach mothers about simple practices to improve the health of their infants. Those practices include breastfeeding, better care for umbilical cords on newborns, swaddling babies to keep them warm, and, of course, frequent hand-washing.

Tielsch's research is published in the Archives of Pediatrics and Adolescent Medicine. I'm Rose Hoban.

When people talk about biofuels, they may mean ethanol from corn or sugarcane, or diesel fuel from soybeans. But another source is algae. Algae contains a lot of oil. There was some research prompted by the oil crisis of the 1970s. But with fuel prices so high, scientists around the world are looking at algae again. Stephanie Hemphill reports on one novel approach to getting algae to grow fast.

HEMPHILL: Roger Ruan has been trying for years to figure out how to turn algae into diesel, economically. He's the director of the Center for BioRefining at the University of Minnesota.

Ruan says there's no question it can be done; some people are already producing algae oil. They're growing it in open ponds. It's used for pharmaceuticals, food supplements, and cosmetics.

RUAN: "Right now, based on an open pond type of system, you can easily get 5,000 gallons [19,000 liters] of oil, and soybean would give you, probably, 50 [gallons, 190 liters]. So that's the kind of difference, that's 100 times difference, right?"

HEMPHILL: So algae can be far more efficient at producing diesel fuel than soybeans. But how do you grow enough algae to make a dent in the nation's energy demand?

Ruan is turning to an unlikely partner: the local sewage treatment plant.

RUAN: "Because it has a lot of nutrients in the wastewater: phosphorus, nitrogen, and so on are all available in the wastewater, and actually you spend lot of money to remove these from wastewater, so if we can kill two birds with one stone, that would be the best, and that's what we're hoping to do."

HEMPHILL: St. Paul, Minnesota's sewage treatment plant sits on the bank of the Mississippi River. The basement of the building where the solids are separated from the liquids is a brightly lit space. It's filled with big steel pipes and valves and tanks.

Off to one side, Ruan's team is setting up a rack of aquariums — the future home of juicy green algae. When everything is ready, some of the partially-treated waste will be diverted into the tanks, where it will feed the algae.

The waste is still full of stuff that's bad for the river, but good for algae.

POLTA: "It's got a fair amount of phosphorus, and some ammonia nitrogen that the algae are going to need."

HEMPHILL: Bob Polta is manager of research and development at the treatment plant.

It's easy to see why Polta likes this idea: every day the facility has to remove four tons of phosphorus and more than 16 tons of nitrogen from the waste stream.

The algae experiment, if it works, will allow them to do some of that removal in a more cost-effective way. And this could be the answer to Roger Ruan's problem of trying to create enough algae to make enough oil to compete with petroleum diesel.

Polta says there's a big potential, both for cleaning wastewater and for producing energy in the same place.

POLTA: "All the wastewater treatment ponds in the small communities are essentially using algae to treat wastewater; it's just that they're not being harvested. We're getting two goals together here, and two research groups. One is essentially taking algae and harvesting the oil and making biodiesel, and another using algae as a treatment scheme, to see if we can make this thing really fit."

HEMPHILL: Polta expects by the end of the year he'll know more about whether this is a practical idea.

Roger Ruan says within six-to-ten years someone, somewhere, will be producing diesel from algae on a commercial scale.

For The Environment Report, I'm Stephanie Hemphill.

Support for the Environment Report comes from the U.S. Department of Agriculture and the Gaylord and Dorothy Donnelley Foundation. You can get in touch with them at

Time again for our Website of the Week, when we showcase interesting and innovative online destinations.

This week it's a site aimed at educating people about some of Earth's most endangered and crucial ecosystems, and urging action to protect them

BARRY: "The is a, true portal site, which means that it has a real search engine of the best-reviewed rainforest information. It tracks news, it provides links, it has a blog. And most importantly, it allows people to take action to get governments and companies to protect rainforests."

Glen Barry is founder of He says the site has information for anyone with even a casual interest in rainforests, though it's really aimed at conservation professionals and others who are passionate about the subject.

BARRY: "For example, right now we're running a campaign to protect the major rivers of the Amazon. And we recently ran a campaign on Laos' plans to dam the last major rainforest wilderness in their country. So it's very much towards motivating people, informing them in order that they will make a stand to protect rainforests for the Earth's future."

Protecting the rainforests, Barry says, is in everyone's interest, no matter where they live.

BARRY: "They're absolutely essential for climate, for water, for forest products, and essentially they're our habitat. So rainforests are more important than ever, and as goes the rainforest will go humanity."

Find out about the key role rainforests play, whether you live near one or not, at, or get the link to this and more than 200 other Websites of the Week from our site,

MUSIC: Zil - "Song for the Rainforest"

It's VOA's science and technology magazine, Our World. I'm Art Chimes in Washington.

If you go to a rainforest, you might run across the Aedes aegypti mosquito. It carries the viruses for dengue and yellow fevers, which infect more than 50 million people each year. A recent discovery published in the Proceedings of the National Academy of Sciences could reduce the prevalence of these diseases. Eric Libby has details.

LIBBY: The Aedes aegypti mosquito commonly lays its eggs in water collected in containers like buckets or abandoned tires, but not all containers are equal.

APPERSON: "We know that they like dark colored containers. And we know that once they get into close proximity to a container, there are odorants from the containers that guide mosquitoes in. And then we know they are stimulated to lay eggs."

LIBBY: Entomologist Charles Apperson at North Carolina State University and his colleagues have identified what attracts those female mosquitoes.

APPERSON: "Our discovery is that bacteria are largely responsible, both for production of the odorants and also for stimulating mosquitoes to lay eggs."

LIBBY: As they digest organic materials like fallen leaves, the bacteria produce chemical compounds called carboxylic acids. Mosquito larvae feed on these bacteria, so the carboxylic acids indicate there will be food available when the mosquito eggs hatch. Adult female Aedes aegypti mosquitoes have evolved to look for these signs.

This insight into mosquito behavior could offer better ways to measure the size of mosquito populations. More importantly, Apperson says, it could lead to improved methods of controlling of mosquito numbers.

APPERSON: "There are two approaches involving chemical control. The one is to place an acutely lethal insecticide in containers and lure them to those containers. And then when they land they pick up this fast acting insecticide and the adults are killed."

LIBBY: The second approach relies on the fact that mosquitoes do not lay all of their eggs in just one container of water. They visit several locations to deposit eggs. Apperson explains that a few pools of water can be treated with chemicals called insect growth regulators. These hormones are crucial for mosquito development, but if too large a dose is present in a certain stage of development, the mosquitoes will die.

APPERSON: "The mosquitoes that walk around on the surfaces that are treated then fly to other containers to lay eggs will transmit and transport some of this chemical because they have contaminated their bodies. They land on the surface of the water and they are able to transmit to the water enough residue of these insect growth regulators that they can control a substantial proportion of the mosquito's larvae that are in that container as well."

LIBBY: Apperson's research demonstrates that a better understanding of mosquito behavior can inspire new tactics in reducing mosquito-transmitted diseases. This is Eric Libby in Washington.

The Everglades is a vast wetland that once covered most of South Florida. Since the 1800s, agriculture and other development has replaced much of the original wildlife habitat. Now, a proposal by the region's biggest sugar producer to quit farming and sell its land to the state for permanent conservation has raised new hopes for the Everglades ecosystem. And as Véronique LaCapra reports, it could give a big boost to restoration efforts.

LaCAPRA: The Florida Everglades is the largest remaining subtropical wetland in the United States. But over the past century or so, half of the floodplain has been drained for human use. In the late 1940s, a massive government engineering project built roads, canals, and levees, to make even more dry land and fresh water available for farming and other development.

AUMEN: "Just in South Florida now we have as many as seven million people, living right up against the Everglades."

LaCAPRA: Nick Aumen is an aquatic ecologist for the Everglades National Park, which protects the southern part of the original Everglades. In what used to be the northern part of the wetland, a huge agricultural area now covers more than 2,800 square kilometers.

AUMEN: "Crops can be grown almost year-round. We're a major source of winter vegetables for a lot of the United States, and South Florida's also a major producer of sugar, sugarcane, for the United States."

LaCAPRA: Producing sugarcane and other agricultural crops takes fertilizer — plant nutrients, such as phosphorus. Mark Kraus is an ecologist with the Everglades Foundation, a non-profit organization that supports Everglades restoration. He says that while phosphorus may be good for sugarcane, it has been devastating for the Everglades' plants, which need very low levels of nutrients.

KRAUS: "The Everglades are adapted to about 10 parts per billion of phosphorus. When you add a lot of additional phosphorus, it promotes the growth of other plants that aren't natural to those low-nutrient systems."

LaCAPRA: Changes in water flow, nutrient pollution, and invasive species have all taken their toll on the Everglades, eliminating 90 percent of the wetland's former two million wading birds, and bringing almost 70 species — including panthers, alligators, and crocodiles — closer to extinction.

And as Nick Aumen explains, restoration projects have been expensive, and slow to show results.

AUMEN: "Perhaps the biggest restoration effort was begun in 2000. That project is projected to take as much as 35 years. Over that 35 year time period, one estimate has it up to about $18 billion dollars."

LaCAPRA: Recent restoration efforts have focused on energy-intensive engineering projects, including a controversial plan to pump water from Lake Okeechobee in and out of underground aquifers to control flooding and water availability.

But according to Mark Kraus, a proposed land deal could change all that.

KRAUS: "This land purchase is going to allow us to restore the Everglades more quickly, in a much less engineered fashion, and in a much more sustainable way."

LaCAPRA: At the end of June, the state of Florida proposed to buy out U.S. Sugar Corporation, the largest sugarcane producer in the United States. The deal would take more than 750 square kilometers out of production, to be replaced by large water storage areas and artificial wetlands.

KRAUS: "This is really exciting. I have been involved in this Everglades restoration project for over 12 years now. We always thought that the right way to do this would be to be able to acquire some agricultural land and provide these large areas of water storage and water cleansing."

LaCAPRA: Under the current terms of the deal, no restoration projects will begin anytime soon: U.S. Sugar gets six years to transition out of farming.

Nick Aumen cautions that seeing environmental benefits from the more than 75,000 hectare buy-out could take even longer. A previous government land acquisition took ten years to start restoration in an area less than a third that size.

AUMEN: "So it would not be surprising for us if this took as long, especially because it's a much larger land area."

LaCAPRA: But Aumen and Kraus agree that if the deal between the state of Florida and U.S. Sugar is successful, it could bring about unprecedented environmental benefits to one of the world's most beautiful — and threatened — ecosystems. For Our World, I'm Véronique LaCapra.

MUSIC: "Our World" theme

That's our show for this week. If you'd like to get in touch - maybe you have a science question for us - email us at Or use the postal address -

Our World
Voice of America
Washington, DC 20237 USA.

Rob Sivak edited the show. Bob Doughty is the technical director. And this is Art Chimes, inviting you to join us online at or on your radio next Saturday and Sunday as we check out the latest in science and technology ... in Our World.