Malaria Control and the DDT Controversy
Although malaria represents a formidable challenge to public health—it spreads quickly via mosquitoes and flourishes in warm climates—it has been successfully combated in some places, including in some warm climates. One of the major obstacles to fighting malaria is reluctance to use the chemical DDT. The chemical was widely and effectively used in the 1940s and 1950s to kill the mosquitoes that carry malaria. The disease was virtually eliminated in Taiwan, the Caribbean, and parts of the South Pacific. Then, in 1962, environmental activist Rachel Carson published Silent Spring, which popularized the idea that DDT had killed millions of birds. The environmental advocacy spurred by Carson’s book, combined with concerns about widespread agricultural use creating resistant mosquito populations, led to an international turn against DDT. In the wake of the government bans on DDT that followed, the campaign against malaria faltered.
Scientists continue to explore and debate the scale of environmental damage caused by DDT and its efficacy in combating the spread of malaria. Nonetheless, it appears that many in positions of influence discourage DDT’s use without adequately considering its anti-malarial value or understanding the distinction between targeted spraying versus indiscriminate use in agriculture.
Malaria Control: Let us Spray
Some defenders of the status quo note that DDT was never prohibited for anti-malarial purposes, only for widespread use in agriculture. Although technically true, this claim is misleading because DDT’s use—even for anti-malarial spraying—has long been discouraged by developed nations and their aid agencies such as USAID. Many in developing nations are under the impression that DDT use is simply off limits.
The targeted spraying of DDT (technically referred to as IRS—indoor residual spraying) is gradually gaining acceptance. In 2006, the World Health Organization issued a position statement in favor of IRS for malaria control, and increasingly it is seen in the development community as an inexpensive, effective and environmentally responsible means to dramatically reduce the spread of malaria.
A more fundamental question is whether developed nations have any business making these sorts of decisions for developing countries in the first place. Surely developing countries should be free to use the same tools (such as DDT) that developed nations used to eradicate malaria. At a bare minimum, aid supplied by international charities and governments should not entail restrictions that prevent the use of valuable methods of malaria control.
It is possible that developing nations will use DDT; it is also possible that they will find other ways of meeting the challenge of malaria. The point is that the scale of human destruction wrought by malaria demands that the prejudices and preferences of developed nations should not interfere with the efforts of developing nations to guard themselves from disease.
Malaria Control and the Problem of Fake Malaria Pills
The international effort to defeat malaria also has been compromised by unscrupulous profiteers who manufacture and market defective anti-malarial medication and sell it to unsuspecting customers. As Andrew Marshall explains in a Smithsonian Magazine article on the subject, some of these pills contain inadequate doses of genuine anti-malarial drugs; these are doubly harmful because, in addition to pretending to treat the disease, they potentially induce malaria parasites to develop resistance to real anti-malaria medication. The same government and private tools used to fight other forms of corruption need to be brought to bear against this despicable form of organized crime.
Malaria Control: A Model for Success
A comprehensive change in anti-malarial policy in the South African province of KwaZulu-Natal in the year 2000 included the use of DDT in insecticide residual spraying (IRS). The Cambridge University anthology Global Crises, Global Solutions found that the addition of DDT to the insecticide spraying, as well as a change in front-line drug therapy, brought about encouraging results. The facilities which introduced the changes, consisting of 1 hospital and 9 clinics, treated 21,874 fewer cases of malaria between 2000 and 2002.
Global Crises, Global Solutions further reported that Anne Mills and Sam Shillcutt of the London School of Hygiene & Tropical Medicine said the interventions, including DDT, were “hugely successful,” and Jacques van der Gaag, a professor of development economics at the University of Amsterdam, called the program shift in KwaZulu-Natal “highly successful.”
Vernon L. Smith, a Nobel laureate and professor of economics and law at George Mason University has said, “The great success of KuaZulu Natal resulting from the use of insecticide spray (40 per cent DDT, 60 per cent delta methrin) and combination drug therapies shows that major reductions in malaria cases can be achieved.”
Malaria Control: Mosquito Nets
Sleeping under nets that keep mosquitoes at bay is one tactic to prevent infection. Nets treated with insecticide are especially effective. Nets also have limitations. One is that they can only be used when people are immobile (e.g., sleeping). Another is that people must be educated and motivated to use them consistently: Many observers in Africa have reported piles of donated nets remaining unused while villagers sleep unprotected. Reasons include discomfort (the nets inhibit ventilation) or a failure to appreciate the level of danger posed by malaria.
This phenomenon points to the importance of ensuring that malaria control methods are understood and supported by local communities. Where the people to be protected are non-participative, no amount of foreign assistance or advice is going to be effective. Bishop John Rucyahana of Rwanda describes the inadequacy of assistance given without appropriate sensitivity and preparation. When United Nations agencies provided mosquito nets, he explains, “The people would hang them around. What do they do to understand how to use them? They don’t know how to use them. They don’t know what they are for. Therefore they will create a new job for the mosquito net… they use them for fishing.” Nets can be one part of anti-malarial campaigns, but no campaign can be successful without empowering individuals in affected communities.
Malaria Control: A Top Priority
In 2004, a group of economists and policy experts ranked a series of solutions to global problems in order to find which issues posed the best opportunities for significant progress. Overall, the Copenhagen Consensus expert panel ranked the control of malaria in their top category of “very good projects.”