Benefits offset by infant deaths? DDT no panacea


Cover of August 2008 Emerging Infectious Diseases from the CDC, featuring: Jan Steen (c. 1625–1679). Beware of Luxury (c. 1665). Oil on canvas 105 cm x 145 cm. Kunsthistorisches Museum, Vienna, Austria

Cover of August 2008 Emerging Infectious Diseases from the CDC, featuring: Jan Steen (c. 1625–1679). Beware of Luxury (c. 1665). Oil on canvas 105 cm x 145 cm. Kunsthistorisches Museum, Vienna, Austria

Weighing risks against benefits for DDT spraying is very difficult. Anti-environmentalists and junk science purveyors claim millions of deaths from DDT’s not being sprayed.

They never tell us about the kids DDT could kill.

When we combine data from North America on preterm delivery or duration of lactation and DDE with African data on DDT spraying and the effect of preterm birth or lactation duration on infant deaths, we estimate an increase in infant deaths that is of the same order of magnitude as that from eliminating infant malaria. Therefore, the side effects of DDT spraying might reduce or abolish its benefit from the control of malaria in infants, even if such spraying prevents all infant deaths from malaria.

*   *   *   *   *

The prohibition of DDT use for malaria control was probably not the sole cause of increasing malaria burden in sub-Saharan Africa (40), and thus DDT will probably not be the sole cure for the malaria epidemic there. Insecticide-treated bed nets, widely used in African households to prevent mosquito bites, are effective (41,42). Synthetic pyrethroid insecticides, cheaper than DDT, are available (43,44). Where DDT is used, all infant deaths, plus birth weights and the duration of lactation, should be counted. Some thought could also be given to a formal trial, since the risk and benefit calculations apply to individual dwellings, and an effective alternative, namely bed nets, is available. (Chen A, Rogan WJ. Nonmalarial infant deaths and DDT use for malaria control. Emerg Infect Dis [serial online] 2003 Aug. Available from: URL: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3020610/)

Go read it — the issue of spraying or not is complex, and this study talks only about infant deaths (there may be greater life saving among older children and adults that would make the infant deaths a trade off policy makers would consider, for example). It’s a study from the Centers for Disease Control, part of a continuing series of technical publications from CDC titled Emerging Infectious Diseases. This series tracks much of the work done to fight malaria world wide.

This is valuable information. It shows the issue is much more complex that just “spray or don’t spray.” It’s also information that JunkScience.com hopes you will not pursue. It’s real information, and it refutes the junk science claims from that site.

(In June 2004 the denialists at Africa Fighting Malaria had a letter published complaining about this paper’s findings, but offering no data in rebuttal.)

Wikimedia Commons image of Jan Steen's painting,

A more clear image from Wikimedia Commons of Jan Steen’s painting, “Beware of Luxury.” Click on cover of journal at top of post for a discussion of this painting and how it relates to infectious diseases.

7 Responses to Benefits offset by infant deaths? DDT no panacea

  1. gebelik says:

    Wishing you Happy New Year 2011! Thankx so much for this! I havent been this thrilled by a blog for quite some time! You’ve got it, whatever that means in blogging. Anyway, Youre definitely somebody that has something to say that people should hear. Keep up the good job. Keep on inspiring the people!

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  2. Ed Darrell says:

    Check out the rants of Steven Milloy at the so aptly-named Junk Science website. His work, and that of Elizabeth Whelan, and much of the work of Paul Driessen until recently, urges DDT as the only answer — spray more of it, and curse those “nasty environmentalists” who stand in the way.

    If you pay attention, you’ll note that indoor use of DDT in limited spraying — usually called “indoor residual spraying,” or IRS — is allowed under the POPs Treaty, has always been part of the arsenal of WHO, and in fact has the backing of almost all major environmental groups, including Environmental Defense, the group whose origins trace back to the first DDT fights in the U.S.

    This is not enough for the genuine DDT-poisoned anti-environmentalists, who insist that there is great danger from not spraying a lot more DDT in Africa, ‘after changing the current policy.’ The only way to spray a lot more would be to start spraying crops in the out-of-doors again — and that’s how we got into this mess in the first place.

    You’ve got certain death only if you rely on DDT alone. Bed nets have reduced malaria from 50% to 85% in areas where they were distributed by the Gates Foundation over the past 5 years, a much more dramatic decline than was ever achieved with DDT in the same areas over a period greater than six months.

    I wish they were straw men. But they’re not. They’re internet and policy thugs, trying with some success to sow dissension and dangerous disinformation wherever they can. For example, there never has been a “panic withdrawal” of DDT from Africa. DDT has been in constant use there since 1946. Use declined after the WHO eradication campaign failed, but that decline was due to the ineffectiveness of DDT against mosquitoes who had developed resistance and immunity. The failure was due to the inability to get enough governments to go along with the campaign quickly enough — the eradication campaign was an attempt to suppress mosquitoes across Africa for six months or so with DDT, long enough for malaria to die out in humans. If malaria were not available from humans, mosquitoes would have nothing to spread. The designers of the plan knew they were in a desperate race, because they understood full well that mosquitoes would rapidly evolve resistance and, they feared accurately, immunity. Alas, several governments could not or would not participate; several other governments simply couldn’t execute. Mosquito resistance to DDT grew faster than anticipated, and the program was stopped in the mid-1960s, a half-decade or more before the U.S. banned agricultural use of DDT (that “ban” has a huge loophole for use of DDT to stop malaria; fortunately, it’s never been needed in the U.S. for that — DDT is still manufactured in several places, and is still in widespread use, especially in India, much of the rest of Asia, parts of Africa and Mexico. In those areas where DDT is still used heavily, malaria has come roaring back anyway.

    DDT is not a panacea — never has been, never can be, now.

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  3. Norma says:

    No matter how you play this game, it still sounds like you’ve got certain death and disability by removing DDT from the market, against assumed problems down the road if it is used. Typical e-reasoning. Who in this century ever says DDT is the only answer? You seem to be attacking straw man events.

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  4. meson says:

    DDT is a substance that should never be used for farming. Because it is virtually indestructible in the nature it will stay in the system for prolonged period. Environmentalist are correct to stop DDT for farming. Health officers and communal leaders however should always keep in mind of using DDT as an option.

    Spraying DDt alone also will not suffice without active measures in the community. Most important of all is to clean up. Malaria mosquitoes hates bright places & breeds in murky water. Simply by keeping a good drainage system and cleaning up the places from rubbish. In Malaysia, there is an act that is often enforced on the public.
    http://www.dph.gov.my/cdc/downloads/law/Act342.pdf

    Even though, Malaria are never eliminated, at the very least we could reduce the amount of deaths. Public awareness & efficient government is the key in eliminating
    malaria deaths. In Malaysia, i’m glad to say that deaths due to road accidents are more likely. Among adults, deaths due to Malaria are eliminated from the top 10 causes.
    http://www.who.int/whosis/mort/profiles/mort_wpro_mys_malaysia.pdf

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  5. sociolingo says:

    Yes, that’s it, thank you.

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  6. Ed Darrell says:

    The journal link you offered didn’t work, Sociolingo. I’m guessing this is the article, yes?

    Acta Tropica
    Volume 102, Issue 2, May 2007, Pages 106-112
    Copyright © 2007 Elsevier B.V. All rights reserved.

    Kassoum Kayentaoa, Mary Mungaib, c, Monica Pariseb, c, Mamoudou Kodioa, Abdoul Salam Keitaa, Drissa Coulibalya, Boubacar Maigaa, Boubacar Traoréa and Ogobara K. Doumboa, Corresponding Author Contact Information, E-mail The Corresponding Author (a) Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy and Odonto-Stomatology, Malaria Research and Training Center, PO Box 1805, Bamako, Mali, (b) Division of Parasitic Diseases, National Center for Infectious Diseases, Center for Disease Control and Prevention, Atlanta, GA, USA
    (c) Public Health Service, US Department of Health and Human Services, USA
    Received 11 July 2006; revised 6 April 2007; accepted 16 April 2007. Available online 21 April 2007.

    Abstract

    Malaria infection during pregnancy is associated with adverse consequences including low birth weight (LBW) and maternal anemia, particularly in primigravidae and secundigravidae. In preparation for a clinical trial of the efficacy of chloroquine (CQ) and sulfadoxine-pyrimethamine (SP) containing prevention regimens during pregnancy, we conducted a one-year cross sectional study in Koro and Bandiagara, Mali using an assessment methodology developed by the Centers for Disease Control and Prevention (CDC) to generate basic data on malarial burden during pregnancy.

    Two hundred and sixty-one and 192 women were enrolled in Koro and Bandiagara, respectively. Rates of placental parasitemia were 17.1 and 42.3% in Koro and Bandiagara, respectively, despite high (70–80%) use of preventive medication (mainly CQ). Low gravidity (1st and 2nd pregnancies) was associated with peripheral (p < 0.001) and placental (p < 0.001) malaria only in Bandiagara, whereas it was associated with low birth weight in both sites (p < 0.001 in Koro and p = 0.002 in Bandiagara). First and second pregnancies were the most important characteristics associated with placental malaria (RR = 2.78, 95%CI 1.81–4.29) and (ARR = 2.06, 95%CI 1.03–4.15) and low birth weight (RR = 4.26, 95%CI 2.50–7.27) and (ARR = 4.51, 95%CI 2.55–8.00). Birth during the rainy season was associated with placental infection in univariate analysis. Characteristics such as younger age, having fever during pregnancy, and unmarried status were associated with low birth weight only in univariate analysis and singleton premature delivery and low gravidity were associated with low birth weight in both univariate and multivariate analysis. Data from this assessment demonstrated the high burden of malaria during pregnancy in Mali. Results had been used by researchers as local reference data and by ministry of health for to stop recommending CQ prophylaxis. The methodology could be used by other malaria -endemic countries to direct their national malaria program efforts.

    Keywords: previous termMalarianext term; Placenta; Low birth weight; Gravidity; Pregnancy; previous termMalinext term

    Corresponding Author Contact InformationCorresponding author. Tel.: +223 222 8109; fax: +223 222 8109.

    The doi link is:
    doi:10.1016/j.actatropica.2007.04.005

    The journal is a subscription journal, so most of us will not be able to see the article.

    Is that the article?

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  7. sociolingo says:

    Thank you for this informative post. As you say, the issue is complex.

    Neonatal deaths and maternal deaths in Mali, for example, are among the highest in the world. The major cause of these (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T1R-4NJ7WC8-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=0a06cde2ad17ce975d849747dc42962b) is maternal malaria. Prevent maternal malaria during pregnancy and you may prevent a large number of neonatal deaths. Yes I agree, controlled studies should be done, particularly comparing DDT and non-DDT pyrethroid targetted spraying. Note I say targetted spraying, not indiscriminate spraying. What does need to be remembered is that the panic withdrawal of DDT over 30 years ago was largely due to the indiscriminate spraying, particularly of crops, in the USA. The effects of which were demonstrably detrimental both to the environment and to people. I don’t see it as a case of only using treated bednets, or only spraying as an answer to pandemic malaria. Bednets are only good if the treatment of them is kept up, if they are used and if they are kept non-holed. In my experience this is almost impossible to achieve in a rural village setting. There are nets available now which are pre-impregnated with insecticide, and some NGOs are distributing them. But they are prohibitively expensive for ordinary people to buy (even subsidised ones are about £5 for a single net), and distribution networks are patchy to say the least. Dipping nets in insecticide is quite hazardous in itself, and again, in my experience, is rarely carried out properly or at suitable intervals in a village (or even town) setting. Nets only protect during sleeping hours, whilst mosquitoes start biting once the sun goes down. Systemic spraying with an approved insecticide can reduce the local mosquito population significantly, and when used in conjunction with bednets, control of mosquito breeding areas and education can significantly reduce malaria in the population. We await the vaccine for malaria with impatience!

    As you can see I feel quite impassioned about this. I’ve been working in Africa for many years and, despite using a bednet all the time, and ‘antimousique’ lotion after dark, I still get malaria regularly, as do most others I know. The loss of man-hours in employment due to malaria has one of the greatest detrimental impacts on the economy of African countries.

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