Thursday, April 20, 2006

TIM LAMBERT, DISSEMINATOR OF MISINFORMATION

The April 14th issue of Science contains an article titled "Environmental Science Adrift in the Blogosphere" by Alison Ashlin and Richard J. Ladle. The article summary states:
Weblogs are a growing global phenomenon with important consequences for science policy and communication. A survey of blogs on environmental topics shows that they vary greatly in accuracy, which indicates a need for participation by informed scientists.
Apparently – I'm not a Science subscriber and don't have access to the article – one of the "excellent, informative sites" recommended is Science Blogs. Well, either Ashlin and Ladle haven't read Deltoid or they're endorsing Tim Lambert's continuing dissemination of misinformation.

Here's Lambert's description of his blogging mission (my bold):
I'm a computer scientist in the School of Computer Science and Engineering at the University of New South Wales in Sydney, Australia. I don't blog about computer science very much but rather about areas of science with political implications such as global warming, the relationship between guns and crime and the use of DDT against malaria. Usually I'm inspired by reading an article and noticing something that doesn't seem to be correct. I then do a little bit of research and before you know it I have a blog post explaining what is wrong and why it is wrong.
So, Deltoid isn't really a science blog, it's a political blog. That's just as well because Lambert gets plenty wrong, especially when it comes to DDT and the fight against malaria. Actually, Lambert doesn't so much get it wrong as he intentionally misinforms. A close look at his DDT-malaria posts makes this obvious.

Lambert's most recent reference to DDT is in a post critical of Greenpeace co-founder Patrick Moore for signing "a pro-DDT petition advocating policies that would cripple the United States' fight against malaria". The embedded link – Lambert continues to bounce my links to his old blog: copy and paste http://timlambert.org/2005/08/ddt11/ – leads to an earlier Lambert post titled "Petition to Kill African Children Now!" in which he observes:
The latest stunt from Africa Fighting Malaria is a petition advocating policies that would cripple the United States efforts against malaria... The goal should be to reduce malaria and you should let the experts figure out the best way to do this. It should not be to spray DDT.
The overall goal of the petition is efficient deployment of resources, not mindless spraying of DDT:
Specifically direct such funds to the actual purchase and deployment of: (1) DDT, or any other proven, more cost-effective insecticide/repellant, for Indoor Residual Spraying (IRS) in any given malarial locality; and (2) of ACTs, or other equally effective and durable drugs, for treatment of malaria patients and reduction in transmission rates.
Lambert never bothers to explain how the petition would kill African children. In view of the findings of a 2005 GAO investigation into U.S. anti-malaria efforts the petition's emphasis is not unreasonable:
Objective 2: Key Challenges to Implementation

Insufficient Financial Resources

Lack of funding for program implementation and donor support activities, including

•Updating of national prevention and treatment policies

•Establishment of monitoring, evaluation, and surveillance systems

•Capital investments—such as the purchase of equipment for IRS programs— needed to support effective policy implementation Examples of reported consequences

•Delays in implementation of updated prevention and treatment policies

• Limited capacity to expand a newly integrated policy involving the coupling of ITN use with IPT

Inability of programs to purchase a sustainable supply of insecticides, spray equipment, and vehicles for mobilization of spray teams needed to effectively implement IRS programs

• Limited use of available research and monitoring and evaluation data to make program implementation more effective
The best I can work out, not only is USAID unsupportive of spraying programs, it has so far provided $0 for the purchase of DDT. Lambert and USAID are both a bit tricky when discussing USAID and DDT, noting correctly that USAID does not ban the indoor spraying of DDT. Tricky wording aside, it's obvious USAID is not supportive of DDT use. (Copy and paste http://timlambert.org/2005/11/usaid-isn’t-against-using-ddt-in-worldwide-malaria-battle/ to access the USAID post.)

Lambert also indicates that the World Health Organization supports DDT use by citing this from a WHO DDT FAQ brochure:
WHO recommends indoor residual spraying of DDT for malaria vector control.
On the surface this appears to be a recommendation of DDT use when, in fact, it's merely recommending how DDT should be used if it's going to be used:
How is DDT used for malaria vector control?

WHO recommends indoor residual spraying of DDT for malaria vector control.
Did Lambert intentionally misinform his readers by citing that quote out of context or is he simply ignorant? I'm inclined to believe the former; either way it's hardly the quality one should expect from a science based blogger who's right into fact-checking. Anyway, the WHO brochure is hardly a glowing endorsement of DDT:
Why is DDT use for malaria vector control so controversial?

DDT is a persistent organic compound. This means that the compound can stay in the environment long after its initial application as an insecticide (up to 12 years). During this time, DDT and its breakdown products may enter the food chain and accumulate in fatty tissues (bioaccumulation). Harmful effects in the wildlife population have been linked to DDT, including the thinning of eggshells in birds exposed to the compound. There are also fears that DDT may have a long-term impact on human health. Although there is currently no direct link between DDT and any negative human health effect, there is growing evidence that it may disrupt reproductive and endocrine function. Opponents of DDT use for vector control argue that its use should be curtailed on these grounds.

Advocates of the continuing use of DDT as an insecticide for disease vector control base their argument on various factors: the unacceptably high levels of mortality and morbidity caused by malaria, the proven effectiveness of DDT in significantly reducing malaria transmission, the relatively low cost of DDT interventions, and the lack of any sustainable alternative in many endemic countries. They argue that the negative environmental and other effects associated with DDT use in the past reflect the massive uptake and bioaccumulation arising from the high amounts used as general agricultural pesticide. The amount of DDT used for disease vector control is negligible compared with that used in agriculture. The advocates also argue that when strictly used indoors, as recommended by WHO, DDT poses very little if any environmental threat.
The main reason DDT is so controversial is because discussions like that above continue to emphasize the supposed hazards associated with DDT use. Tim Lambert's intentionally misleading posts just add to the confusion.

Update: Here's another example of WHO's negative view of DDT, this from the WHO Expert Committee on Malaria 20th Report:
3.2.1Indoor residual spraying with insecticides

In many programmes, mainly in the Americas and some countries in Asia, indoor residual spraying continues to be the main vector control measure implemented. There is, however, a tendency to reduce reliance on spraying, and there is also a marked decrease in the use of conventional residual insecticides, such as DDT, which have been replaced by new-generation insecticides, such as the pyrethroids, at considerable financial cost to the programmes. Improvement in local knowledge of malaria epidemiology (especially disease transmission), with refinement of surveillance mechanisms and proper use of collected data, could lead to the implementation of more selective vector control and further reduce reliance on indoor residual spraying.

8.1.1Indoor residual spraying

Non-selective coverage, as used for DDT and other insecticides in the past, is no longer a recommended strategy. Reduction of widespread coverage is still needed in the Americas, Asia and in some areas of Africa (where malaria transmission is focal and unstable, and in epidemic-prone areas). Given the financial and human resources involved, combined with the potential for vector resistance and environmental concerns, indoor residual spraying should be used only in well defined, high or special risk situations. DDT is being phased out because of its previous widespread use in the environment, and the resulting political and economic pressure.
The pressure was on back when this report was written, around the time the Stockholm Convention on Persistent Organophosphate Pollutants (POPs) Treaty was being negotiated, to eliminate DDT from the anti-malaria arsenal. Tim Lambert often claims DDT has fallen into disfavour mostly because mosquitoes became resistant to it; the WHO report indicates that there were political and economic pressures but does not specifically mention DDT resistance as a factor.

To be continued...

1 Comments:

Blogger GMO Pundit said...

There are at two substantial issues I have taken up with Lambert but failed to get any indication on his part of an interest in the downside of opposing DDT.
Taken together, the two issues prove anti-DDT activism has killed people and caused a large amount of disease, numbersing many thousands of cases.. Exactly
First, Amir Attaran (Dr Roberts and others work shown malaria got out of control in South America after DDT discontinuation, but was sucessfully controlled in the areas where DDT was retained. This is best seen in:

Balancing risks on the backs of the poor. Attaran A, Roberts DR, Curtis CF, Kilama WL. Center for International Development, Kennedy School of Government, Harvard University, Cambridge, Massachussetts 02138, USA amir_attaran@harvard.edu.

(Note though the death rate among malaria cases in South Americ is much lower than in Southern Africa.)



THE British Medical Journal has an open access article discussing effort to ban DDT- a ban Lambert repeatedly claimed was never attempted or implemented.
Doctoring malaria, badly: the global campaign to ban DDT
http://bmj.bmjjournals.com/cgi/content/full/321/7273/1403

DDT for malaria control should not be banned
BMJ 2000;321:1403-1405 ( 2 December )

Amir Attaran, director, international health research, a Rajendra Maharaj, deputy director, vector-borne diseases. b
a Center for International Development, Harvard University, Cambridge, MA 02138, USA, b South Africa Department of Health, Communicable Disease Control, Private Bag X828, Pretoria 0001, South Africa

Correspondence to: A Attaran amir_attaran@harvard.edu

The treaty on persistent organic pollutants---POPs---will be finalised at the United Nations Environment Programme meeting in Johannesburg, 4-9 December. One proposal is to ban DDT, still used by many countries for controlling the mosquitoes that spread malaria. It should not be banned, argue Amir Attaran and Rajendra Maharaj, specialists in malariology and also international development and law---there's no evidence that spraying with DDT harms anyone. The issue is not straightforward, says Richard Liroff, director of the World Wildlife Fund's alternatives to DDT project; the treaty raises a series of equity challenges.
KEY QOTE FROM THIS PAPER
South Africa illustrates these limitations in practice. Facing pressure from environmentalists, the national malaria control programme abandoned DDT in favour of more expensive pyrethroid insecticides in 1996. Within three years, pyrethroid resistant A funestus mosquitoes invaded KwaZulu-Natal province, where they had not been seen since DDT spraying began in the 1940s. Malaria cases then promptly soared, from just 4117 cases in 1995 to 27 238 cases in 1999 (or possibly 120 000 cases, judging by pharmacy records). Other provinces experienced similar catastrophes, and South Africa was forced to return to DDT spraying this year. It had little alternative: no other insecticide, at any price, was known to be equally effective.

This experience raises a challenging question: if the wealthiest, most scientifically advanced, and least malarious major country of sub-Saharan Africa cannot make do without DDT, how can superendemic and impoverished countries like Tanzania, Congo, or Mozambique do so? Should they be asked to?

We conclude that the public health benefits of DDT amply outweigh its health risks---if, indeed, such risks exist at all. For doctors or their banner groups such as Physicians for Social Responsibility to campaign otherwise is not only wrong but outrageously unethical. Risk-benefit trade-offs are part of public health and medicine, and we would be swift to condemn the malpractice of doctors who would from ideology deny their patients cyclosporin, tamoxifen, chlorambucil, azathioprine, or any other lifesaving drug known to be a human carcinogen.12 The situation with DDT and malaria is hardly different. The public health malpractice of its avoidance must stop.


The second substantive issue that Lambert avoided in discussions with me is the epidemic of malaria that occured after DDT was banned in South Africa in the leadup to the Joberg 200 conference. When DDT was eventually reintroduced the epidemic was bought under control.

S Afr Med J. 2005 Nov;95(11):871-4
Impact of DDT re-introduction on malaria transmission in KwaZulu-Natal.
Maharaj R, Mthembu DJ, Sharp BL.
Malaria Research Programme, Medical Research Council, Durban, South Africa. rajendra.maharaj@mrc.ac.za

OBJECTIVES: To determine whether the re-introduction of DDT in KwaZulu-Natal had any effects on malaria transmission in the province. DESIGN, SETTING AND SUBJECTS: The 2000 malaria epidemic in KwaZulu-Natal has been attributed to pyrethroid-resistant anopheles mosquitoes in the area. Previous studies have shown that these mosquitoes are still susceptible to DDT. To determine whether DDT re-introduction had any impact on malaria transmission in KwaZulu-Natal, the following variables (pre- and post-epidemic) were investigated: (i) the number of reported cases; and (ii) the distribution of Anopheles funestus in relation to the insecticides sprayed. OUTCOME MEASURES: The notified malaria cases and the distribution of A. funestus were measured to determine the effects of DDT re-introduction on malaria transmission. RESULTS AND CONCLUSION: After DDT re-introduction, the number of malaria cases decreased to levels lower than those recorded before the epidemic. A. funestus appears to have been eradicated from the province. The combination of an effective insecticide and effective antimalarial drugs in KwaZulu-Natal has resulted in a 91% decline in the malaria incidence rate. Unfortunately the continued exclusive use of DDT within the malarious areas of the province is threatened by the emergence of insecticide resistance.

1:03 PM  

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