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September 25, 2006


E. coli also a concern for home gardeners; Bug-resistant bananas; GM cotton in Burkina Faso


Today in AgBioView from www.agbioworld.org: September 25, 2006

* A chain of weak links on spinach
* E. coli also a concern for home gardeners
* Spinach from Natural Selection Foods
* Fresh leafy greens – Are they safe enough?
* Israeli company develops bug-resistant bananas
* Monsanto and Syngenta to expand testing of GM cotton in Burkina Faso
* ITSSD: IP-Based Innovation, Not IP Opportunism, is in Brazil's Best Interests
* DDT's return is a good thing. Really


A chain of weak links on spinach

The system's set up to maximize profits at every level, not to ensure safety or to forestall health threats

- Newsday, BY DR MARC SIEGEL, September 25, 2006

The current outbreak in spinach of Escherichia coli 0157:H7 that's scaring my patients didn't occur in a vacuum. It is part of a culture of dealing with animals, plants and food that allows the spread of harmful bacteria.

There is a chain of events that occurs from cow to manure to contaminated water to crops to food that eludes regulation. Farmers concentrate on beefing up their cattle or maximizing their milk without sufficient regard to collateral damage from contagion. There is a crucial gap between U.S. Department of Agriculture supervision of animals and plants and Food and Drug Administration efforts by the time a product is labeled as food.

Outbreaks occur mainly because those monitoring each link in the chain of infection are not paying attention to the next link.

Cattle farmers are not thinking of the harmful effects of manure; they are concerned about selling their product. Sellers of organic fertilizer made from manure are hoping their product will grow vegetables, not concerned that it will contaminate water or spinach. Salad makers screen and cleanse their food but can't always afford the expensive equipment to detect the most elusive bacteria. There is also not enough separation between animal and animal products before they become human food.

Multiple studies in the agricultural literature have shown that dairy cows shed harmful bacteria at variable rates. This shedding is dependent on several factors that could be controlled, including the animal's feed. Studies have shown that changing feed from grain to hay decreases the acidity in the gut of cows that allows bacteria to thrive. Because very small amounts of 0157:H7 can cause human infection and because shedding of the bacteria by cows is so variable, proper surveillance of manure is also crucial in preventing outbreaks. But sophisticated laboratory techniques that are most effective at detection are very expensive and not commonly used. Current agricultural attempts to contain manure and organic fertilizers at the farm are not sufficient to prevent occasional seepage into water supplies, which sparks outbreaks.

Once an outbreak occurs in humans, the FDA is forced to play catch-up, in this case by putting an umbrella advisory over all spinach that sends the inadvertent message that the disease is much more widespread than it is. Because food is processed and packaged in one state and then mixed and sold across several states, containment and control become more difficult.

E. coli 0157:H7 is a strain that produces a toxin that breaks down the lining of blood vessels, causing bloody diarrhea in humans and sometimes kidney failure. Because cows lack the receptor on their cells to absorb the toxin, they don't show symptoms that they are carriers of the bacteria.

Before the current outbreak, there were close to 20 outbreaks linked to salad since 1995 in which the crops were fed water contaminated with E.coli from manure.

By feeding cows antibiotics, our meat industry promotes drug resistance and helps create genetically altered superbugs that can then be passed to produce as fertilizer. The current strain of E. coli that has caused the outbreak appears to be very virulent, making people sicker in dozens of states and causing more kidney failure than is usual for this strain.

A greater degree of vigilance and a new system of coordinated prevention and regulation are necessary to help prevent outbreaks. Studies also have shown that sodium chlorate as well as "pro-biotic" bacteria fed to cows - besides feeding them hay - may help to decrease the prevalence of this deadly strain. Feeding cattle antibiotics is a practice that should be banned.

Beyond the cow, it would help if there were more preventive measures in place on farms, especially in California. Since 1995, nine of the outbreaks in lettuce or spinach have been traced to the Salinas Valley. Currently, state investigators there are still trying to trace the outbreak to specific equipment in the salad factories, belatedly backtracking the spread from Natural Selection Foods out to other salad makers.

This outbreak is best understood by seeing it in perspective. Media-driven fear can cause us to wrongly perceive all salad as unsafe. But this fear also can serve as an important wake-up call.

As a physician, I am very aware of the bacteria or viruses a dog or cat harbors that can infect my patients during a bite. I know how to treat them, but, more important, health agencies are geared to prevent these infections through pet-control programs.

We need the same kind of comprehensive approach when it comes to animal management and food safety. Food safety needs to be better regulated with a more integrated prevention-oriented system involving the Agriculture Department, FDA and a new food safety agency to bridge the gap.

Dr. Marc Siegel is an associate professor of medicine at the New York University School of Medicine. He is the author of "False Alarm: The Truth About the Epidemic of Fear."


E. coli also a concern for home gardeners

- Palladium Item, Sept 22, 2006

Warnings this week about the dangers of contaminated spinach may make you glad you're a home gardener, but even we aren't immune to this problem.

Gardeners who use manure as fertilizer should know their growing plants could become contaminated by harmful pathogens unless they follow manure management rules.

E.coli, salmonella and listeria can be transferred to humans from animal manure, which may also contain parasites like roundworms and tapeworms. Manure from pigs, dogs and cats should never be used in gardens or compost because it may contain parasites that can infect humans.

The risk of food contamination is greatest with fresh manure, which should never be applied to the garden or put in the compost pile. Anyone who works in a garden where fresh manure has been applied or eats produce from it is at high risk of becoming ill.

Besides being a health risk, fresh manure is unpleasant to work with and will burn growing plant roots because it's too high in nitrogen.

If you want to use manure on the vegetable garden, use only composted, rotted manure. Manure should be composted in its own pile for at least six months to reduce the risk of contamination. Rotted manure should be applied to the garden before anything is planted and worked into the soil.

The manure sold in bags at garden centers has been composted and dried. Follow the label directions in applying it on your garden.

Well-rotted manure can be beneficial to the garden soil because it not only provides fertilizer but it may improve the soil's tilth or texture. Manure from a horse or cattle stable usually contains bedding material like straw or sawdust, which will help loosen clay soils.

Extension horticulturist Rosie Lerner warns that root vegetables and other crops whose edible parts grow below the ground have the greatest risk of contamination because they are in contact with potentially contaminated soil.

Vegetables like potatoes, carrots, beets, sweet potatoes, turnips, parsnips and onions should be thoroughly washed and possibly peeled to decrease risks.

Leafy vegetables like lettuce, spinach and cabbage are also at risk of contamination because their edible parts are in close contact with the soil and they have crinkly leaves that catch soil particles, Lerner said.

Removing the outer leaves of cabbage and lettuce and thorough washing is recommended. Put spinach or leaf lettuce in a bowl and fill it with cool water. Swish the greens around and then lift them out into a colander to drain. You'll be amazed at the amount of soil sinking to the bottom of the bowl.

Empty and rinse the bowl, return the greens to the bowl and repeat the washing. Keep repeating the process until you see no more soil in the water. Drain the greens well, bag them and refrigerate.

Raising your own vegetables is the best way to control the quality of the produce you eat. The fact that E. coli can be absorbed into the plant and is apparently able to cause illness even after cooking is a concern that isn't going to go away.

It's a little late in the growing season to start a spinach or lettuce bed in the garden now, but a cold frame will let you grow your own greens through much of the winter. A cold frame, a wooden box filled with soil and covered with a transparent lid, is essentially a mini-greenhouse on the ground. An old storm window will make a good lid.

The trick to success with a cold frame is remembering to raise the lid when the sun is shining so the plants you're growing inside don't cook. Then you have to remember to close it at night so the plants don't freeze. There are automatic devices you can buy from garden catalogs and stores that are temperature-controlled and will automatically raise and lower the lid for you.

It's also late to find garden seeds, but many mail-order garden companies sell seeds year round. Johnny's Selected Seeds (Johnnyseeds.com) usually has salad seeds available in the fall, as well as offering a book on building and using cold frames.


To the Editor:

The spinach from Natural Selection Foods that has been implicated in the E. coli outbreak was produced to supply the organic foods industry, whose standards demand the use of supposedly safe natural fertilizers like sterilized cow manure. But the use of that manure — as opposed to the use of presumably less safe manmade fertilizers — could well be the source of the current outbreak.

In fact, from a fertilizing perspective, there are no chemical differences between the two fertilizers, but the sterilized manure has been implicated in far more disease outbreaks than manmade fertilizers.

The Centers for Disease Control and Prevention in the United States and its British counterpart have both gathered statistics suggesting that there is a substantially greater likelihood of contracting E. coli-based and similar illnesses from organic produce than from conventionally grown produce.

As a consequence, any attempt to ameliorate disease risk from produce must investigate farming practices like those employed by organic farmers.

Elliot Entis
Waltham, Mass., Sept. 21, 2006

IAFP to host rapid response symposium: Fresh leafy greens – Are they safe enough?

- (VIA AGNET), 22.sep.06

Des Moines, Iowa (September 22, 2006) The International Association for Food Protection will host a Rapid Response Symposium titled, Fresh Leafy Greens - Are They Safe Enough?
On October 6, 2006 at the Key Bridge Marriott in Arlington, Virginia. The symposium will bring leading experts and stakeholders together for a science-based discussion on the latest findings from the recent nationwide spinach outbreak. It will center on lessons learned and current strategies to improve the safety of leafy greens and similar produce.
The recent widespread foodborne outbreak linked to fresh, bagged spinach has called into question the safety of fresh leafy greens. Since 1995, there have been 19 reported outbreaks of foodborne illness in the U.S. caused by E. coli O157:H7 for which lettuce or leafy greens were implicated as the outbreak vehicle. Given these findings, are fresh leafy greens safe enough? Are current measures adequate to ensure consumer safety?
What are the latest risk management strategies that can be implemented to further protect public health? These and other questions will be discussed on October 6, in Arlington. A symposium schedule may be reviewed online at www.foodprotection.org. Hotel accommodation and registration information for the one-day program can also be found at the IAFP Web site.
For more information on the IAFP Rapid Response Symposium please contact the Association office at 800.369.6337; 515.276.3344; fax: 515.276.8655, E-mail:
info@foodprotection.org; or Web site: www.foodprotection.org


Banana lovers rejoice - Israeli company develops bug-resistant bananas

- Israek21C, By David Brinn, September 25, 2006

If you eat five bananas a week, there's a good chance that one of them has its genetic origins in Israel.

Driving north of Nahariya towards the Lebanese border, you pass fields and fields of banana crops at nearby Achziv as well as on Kibbutz Rosh Hanikra. It's at the latter kibbutz where biotech company Rahan Meristem (1998) LTD, a world leader in banana biotechnology, has its offices and laboratories.

"We're the largest producer of banana tissue cultured plants in the world - producing about 10 million a year. They're sold all around the world. We calculated that approximately 20% of the bananas that are marketed throughout the western world originated or were selected at Rahan," said Dr. Eli Khayat, head of research and development at Rahan and a professor of plant biology at Hebrew University and the Technion.

"Most of our research is on bananas - trying to improve the quality of the crop - using molecular genetics to breed bananas that ripen slower and have a longer shelf life," he told ISRAEL21c. "These are parameters which are important to both the grower and the consumer. Our goal is to breed plants, and given that bananas are seedless, the only means to produce elite clones is by genetic engineering."

With a total production of approximately 60 million tons per year, banana and plantains (bananas which are grown for cooking) have become a major crop worldwide, exported from tropical countries to almost every part of the globe. But as a result of its natural sterility, most banana varieties have yet to be genetically improved via biotechnological tools.

Now in a new breakthrough development with far-reaching implications, Khayat and his team have successfully completed a field trial that validates its latest accomplishment - the complete resistance of banana plants to a wide range of pathogenic nematodes - tiny microscopic worms that damage plants from their root.

Nematodes are considered one of the most destructive pathogens attacking bananas in all zones of production. Vegetative propagation, using infested corms or suckers, has disseminated this pest throughout the world. Yet, most effective nematicides have been banned in large parts of the world because of their polluting effect on the environment. As a result, nematode resistance is considered to be a highly attractive attribute that is estimated to reduce growers' expenses by hundreds of millions of dollars every year.

According to Khayat, the accomplishment has taken six years of research and testing.

"The technology involved was developed jointly by Rahan, Bar Ilan University and Hazera, an Israeli seed company. The result is transgenic bananas, bananas that have been genetically modified. They are completely resistant to nematodes, by use of a special technology called RNAi," he told ISRAEL21c.

"We recently conducted field trials, growing plants in an area heavily infested with nematodes, and the plants showed complete resistance. They weren't affected at all. The nematodes couldn't reproduce on the plants."

Founded in 1974 by members of the kibbutz, Rahan Meristem was the first operating commercial tissue culture laboratory in Israel. It was established as an extension of an existing well-recognized fruit trees nursery in Israel.

Initially, Rahan's workers developed new procedures for large scale, in vitro, clonal propagation of over 200 plant genera including ornamental, industrial, fruit and vegetable crops.

By the mid 1980s the company focused on a smaller variety of plants, and in vitro propagated banana plants became the leading product. Combined with the high level of pre-existing expertise of banana agrotechnology on Kibbutz Rosh Hanikra, Rahan became a center of research and consultation for the banana industry throughout the world.

A formal R&D department was established in 1991 in order to provide technical support to the different branches of the company and develop new products and technologies, as well as other technical services. Khayat joined the company in 1992 when he returned to Israel from a post as associate professor at Rutgers.

When Khayat talks about molecular genetics and how it relates to bananas, it sounds like the Israeli kibbutz of yesterday - with oranges, dancing, and tractors, has turned into a futuristic science fiction mystery.

"We're producing and breeding banana plantlets from tissue culture. They're banana clones. Bananas are seedless so the only way to improve them is by selection, a process we work on at our premises on the kibbutz. The selected clones are propagated by means of tissue culture. You can amplify a single clone to as many as you want," Khayat explained.

When the topic is cloning and genetic engineering, Khayat knows that he's treading in controversial territory, with large movements around the world opposed to genetically engineered food. But he provides thoughtful explanations as to why he thinks Rahan is on the right path.

"I think the opposition derives from a general view about genetically engineered plants as being unknown and a mystery. It's the same as the feelings about vaccines at the beginning of the 20th century - the view that it will cause something worse that what it's protecting against," he said.

"Genetic engineering is much safer than insecticides to both the environment and to humans, but politically, it's a problem with environmental groups. For example, in general the fields where bananas are grown are treated with nematicides to avoid infestation by nematodes. The volume of insecticide could not only kill humans, but even elephants. They are very nasty chemicals, and the damage to the environment as a result is very heavy."

"With transgenic plants, especially bananas due to the fact that they can't cross-fertilize and don't have seeds, there's no dissipation of the genetic material anyway - it's contained within the plant. So there's no danger to humans or to the environment. The plants can grow in areas that weren't treated with insecticides."

Khayat pointed out that in Costa Rica, where much of the population works in the banana industry, there was a large occurrence of male sterility due to nematicides. He added that over time, many countries have accepted genetically engineered food products as a fact on the ground.

"In the US, it's a standard practice. In Europe, by and large, there is still objection, but it's slowly breaking down. Now in Spain and Germany, the import of transgenic seeds is allowed, but it's still case by case."

Rahan's nematode-resistant technology must now pass through a regulatory process in the US which is very expensive, and Khayat acknowledges that Rahan, which employs 130, will not be able to carry this out alone.

As a result, the company is currently looking for strategic partners in the US who will take over the process. The company is also looking for partners in the banana industry, such as Dole, Chiquita and Del Monte, who might be interested in developing Rahan's technology. Khayat admits that negotiations with one of these two banana giants is now underway.


Monsanto and Syngenta to expand testing of GM cotton in Burkina Faso

- EIU Viewswire via Agnet, September 22, 2006

Two foreign agro-industrial companies will be permitted to expand testing of genetically modified (GM) cotton during the 2006/07 farming season, according to Zourata Lompo, the director of the Agence nationale de biosécurité.

US-based Monsanto of the US and Switzerland's Syngenta were chosen from an initial list of four companies offering a total of 14 varieties of cotton; the two firms will plant six strains of GM cotton. Local civil and environmental groups have expressed concerns about the planting of GM varieties, and Ms Lompo emphasised that the country has not yet decided to release GM seeds into the general farming system, and that these plantings will be part of a process of testing and experimentation that has been under way for two seasons.

Strict security conditions are being demanded at the test stations to guard against GM seeds reaching regular farms. If those conditions are not met or the companies provide inaccurate information, authorisation may be withdrawn. Under new legislation that entered into force in April, violation of biological security regulations are punishable by prison terms of up to 15 years and fines of up to CFAfr5bn (US$9.7m).

The Union nationale des producteurs de coton du Burkina, which has been closely monitoring the testing process, reports that 663 farmers have so far planted test fields of genetically modified cotton, on a total of 316 hectares of land in several parts of the country.

Burkina Faso is a leading proponent of biotechnological research within the regional Union économique et monétaire ouest-africaine, and the francophone grouping is backing its efforts with the equivalent of US$24m in financial support. If Burkina Faso's experiment is successful a number of its neighbours are likely to be interested in following a similar course.


ITSSD: IP-Based Innovation, Not IP Opportunism, is in Brazil's Best Interests

A New ITSSD Article Discusses How, by Rediscovering the Value of Private Intellectual Property Rights, Brazil Can Stimulate Domestic Innovation and Generate Economic Growth

PRINCETON, N.J., Sept. 21 /PRNewswire/ -- While the government of Brazilian President Luiz Inacio Lula da Silva works diligently to appear as a political moderate and a dependable market-friendly force within a highly volatile and blatantly populist region of the world, international business, trade and regulatory expert Lawrence A. Kogan of the ITSSD reports how Brazil, under Mr. Lula's leadership, is actually working to undermine exclusive private property rights and free enterprise globally.

In a new article appearing in the peer-reviewed International Journal of Economic Development (IJED), Mr. Kogan documents how the Brazilian government, assisted by ideological activists, academics and politicians, has brazenly led a bloc of emerging and less developed economies to craft a highly controversial anti-intellectual property right (IPR) legal framework. According to the article, Brazil is believed to be promoting this new international paradigm in order to divert attention away from its weak national education and innovation systems, to gain negotiating leverage at the now-stalled WTO Doha round trade talks, and to project itself politically as the international champion of a development agenda that calls for a massive redistribution of global wealth and knowledge (technology transfer) at or below concession rate prices.

Rather than embrace what clearly amounts to a national and global policy of (IP) opportunism, which aims to ensure open source, universal access to (life sciences and information technology) knowledge for all at the expense of exclusive, privately-owned IP rights, the article explains why Brazil should instead adopt a proven 'bottom-up' policy of domestic market-based discovery and innovation premised on strong individual private property right recognition and protection. This requires, says Mr. Kogan, that "Brazil not only invest in university and government-led basic research and development programs, but also in a WTO-consistent, market-friendly national enabling environment that fosters Brazilian and foreign industry commercialization of government-financed inventions into market-relevant innovations bearing temporary but exclusive private property ownership rights."

The article cites numerous studies and actual examples of how such a well designed and implemented national enabling environment can lead to a virtuous cycle of increased research and development (R&D)-related foreign direct investment, greater Brazilian and foreign company R&D collaborations and technology transfers, and expanded intergovernmental science & technology, financial, and trade cooperation. The article also features introductory remarks by three well-known experts: Dr. Pat Choate, Director of the Manufacturing Policy Project, and author of Hot Property: The Stealing of Ideas in an Age of Globalization; Legal Studies and Meigs Professor, O. Lee Reed, of the University of Georgia; and Dr. John Kilama, President of Global Bioscience Development Institute, Inc.

The article entitled, Rediscovering the Value of Intellectual Property Rights: How Brazil's Recognition and Protection of Foreign IPRs Can Stimulate Domestic Innovation and Generate Economic Growth, is accessible on the IJED's website at: http://www.spaef.com/IJED_PUB/v8n1-2.html and http://www.spaef.com/IJED/IJED_PUB/index.html . An Executive Summary of the article is also accessible on the ITSSD's website at: http://www.itssd.org/publications.htm .

The ITSSD is a non-partisan non-profit educational organization devoted to the promotion of a positive paradigm of sustainable development consistent with private property, free market and WTO rules-based principles. The ITSSD examines international law as it relates to trade, industry and sustainable development around the world. ITSSD studies are accessible at: (http://www.itssd.org/library.htm).


DDT's return is a good thing. Really

- Globe and Mail, By Margaret Wente, 23.sep.06n (VIA AGNET)

Columnist Wente writes that malaria is the leading killer of African kids under 5, a curable, preventable disease that carries off the very young, and leaves adults too sick to work. In Tanzania, malaria kills more people than AIDS and every other infectious disease combined. Worldwide, malaria kills a million people a year -- most of them in sub-Saharan Africa -- and infects 500 million more. Most victims are young children.

Among the most effective ways to control malaria is indoor spraying with DDT. It can reduce malaria transmission by up to 90 per cent and, when used properly, is safe for both humans and the environment. Yet, for many years, DDT has been taboo. African nations dismantled their spraying programs because donors wouldn't fund them, even though spraying indoors never was dangerous.

Last week, all this began to change, when the World Health Organization announced a major policy reversal. From now on, it will aggressively promote the use of DDT to fight malaria. "Extensive research and testing has demonstrated that well-managed, indoor, residual house-spraying programs using DDT pose no harm to wildlife or to humans," said Dr. Arata Kochi, director of the WHO's Global Malaria Department. He challenged environmental groups: "Help save African babies as you are saving the environment."

The story of DDT in Africa is a monumental tragedy. It is the story of how the misguided environmental fears of well-meaning Westerners denied the world's poorest people access to one of the most effective disease-prevention tools. Amir Attaran, a committed environmentalist, knows the story all too well. It's partly owing to his efforts that the WHO finally reversed itself.

"Every day, the number of kids dying of malaria equals seven Boeing 747s going down," he said from his Ottawa office. "There's a massive constituency for other diseases, but malaria? It kills African kids, so nobody gives a damn."

Mr. Attaran has an unusual combination of skills and interests. He has a PhD in cell biology and is an expert in environmental law. He has taught at Harvard and Yale. At Harvard, he worked with economist Jeffrey Sachs to persuade the UN to set up a Global Fund for aids, malaria and tuberculosis. Last year, he was recruited to the University of Ottawa to be Canada Research Chair in Law, Population Health, and Global Development Policy.

Mr. Attaran is no stranger to Canada. In the late 1990s, he landed his dream job with the Sierra Legal Defence Fund in Vancouver. There, he helped win an important case on toxic-waste law before the Supreme Court of Canada. In the summer of 1998, he attended a UN conference in Montreal, negotiating a global treaty on eliminating 12 chemicals known as persistent organic pollutants. Eleven of those 12 had no merit. The 12th was DDT.

"I knew from my time studying infectious diseases that DDT was awfully useful to control malaria," he says. "I have a deep commitment to the environment. But I'm also a scientist. I want to see the data. And I'm not about to sell African kids down the river."

Working in his spare time, Mr. Attaran fought to get the ban softened.

"My view was, let us ban DDT for all uses other than health, and carve out an exception for that." With the assistance of a small international group called the Malaria Foundation, he drafted an open letter making the case for DDT. He e-mailed it to colleagues and circulated it on the Internet. In a few months, he got 400 leading doctors and scientists from around the world, including several Nobel Prize winners, to sign it. Eventually, a compromise was negotiated (he drafted it), and the final treaty made an exception for DDT when used for public health.

"By this time, the environmentalists hated me," he recalls. "I'd just driven a stake through their aspirations to ban DDT once and for all." Although his boss was supportive, his stance on DDT eventually cost him his job.

It was Rachel Carson who turned DDT into history's most notorious insecticide. Her 1962 book, Silent Spring, persuaded most of the world that DDT was a lethal killer of wildlife. But the book dealt only with heavy agricultural spraying, not with indoor spraying for malaria control. In 1972, DDT was banned in the West.

Although DDT was in widespread use for less than 30 years, it probably prevented more death and disease than any other manmade chemical in history. In India, there were a million malaria deaths in 1945; by 1960, thanks to DDT, there were only a few thousand. It's estimated that by 1972, DDT had saved 500 million lives.

Although Western donors wouldn't fund it, some African nations kept using DDT for malaria control. Among them was South Africa. In 1995, it finally bowed to pressure and stopped using the chemical. In 1996, it was struck by one of its worst malaria epidemics ever. Malaria cases soared tenfold: By 2000, there were more than 60,000. Meantime, just across the border, Swaziland continued spraying with DDT. Malaria did not increase.

Despite the global treaty's compromise on DDT, leading aid agencies (including the World Bank, USAID and Canada's CIDA) refused to fund its use. So Mr. Attaran doggedly persisted with his campaign. "All the agencies who are supposed to help the poor were hurting them," he says. "The WHO responded by hiding from the issue."

Other critics are less kind. Among them is James Shikawati, co-ordinator of the Africa Resource Bank. DDT policies, he argues, are "evidence of how developed countries' intellectuals inadvertently contribute to deaths in poor countries." Malaria "has wrecked the continent for over 30 years, simply because some policy-makers thought it wrong to kill mosquitoes using chemicals."

Instead of spraying with DDT, many aid agencies (including CIDA) have endorsed the use of treated bed nets to combat malaria. Bed nets have their place. But they only work when people are under them. And mosquitoes don't only bite at night. In Mr. Attaran's view, the wrangling over bed nets versus spraying is stupid. "It's like having a debate over whether you should use chemotherapy or radiation to treat cancer. You need both. You need everything you've got."

The WHO's new policy is a major breakthrough. It means Western governments and donor agencies will start to fund DDT spraying programs.

But Mr. Attaran's battle isn't over. Bizarrely, the anti-DDT lobby includes major African agricultural producers, who are worried that DDT might contaminate their crops and ruin their export markets. In Uganda, the ministry of trade has threatened to take the ministry of health to court if it goes ahead and uses DDT.

Then there's the matter of persuading Western aid agencies to change their policies.