Eradicating malaria: Don’t dismiss DDT

[Editor’s note: This is a guest post written by Danielle Brown.]

“There is more money put into baldness drugs than into malaria,” said Bill Gates at the annual Technology, Entertainment, Design conference. To underscore his point Gates released a jar full of mosquitoes into the crowd, stating, “there is no reason that only poor people should have this experience [malaria].” He quickly assured the audience that those particular mosquitoes were not carrying malaria.

For many, especially the poor, malaria is a reality and a daily threat to their lives. Gates’ presentation pointed to the fact that malaria has been eradicated in developed nations but remains a problem for many equatorial countries. Approximately half of the world’s population is at risk of malaria, and it remains the single greatest killer of children living in lower-income countries. In 2006 alone, there were 247 million cases of malaria and 880,000 deaths. For a disease that is preventable and curable, these numbers are far too high.

Gates also raised an important question: How do you stop a deadly disease that is spread by mosquitoes? His response for prevention includes insecticide-impregnated bed nets and indoor residual spraying using the insecticide dichloro-diphenyl-trichloroethane (DDT). The two, used in combination, can cut deaths from malaria by 50%.

Despite this potential, the global response to this question is defined in part by a debate over the safety of DDT, framed by the Stockholm Convention on Persistent Organic Compounds and by WHO guidelines regarding use of DDT. The Stockholm Convention outlines a plan for the long-term elimination of the production and use of DDT by 2020, while granting DDT an exemption for use in public health. This exemption is conditional on whether alternative insecticides that are as cheap and effective as DDT exist. However, such alternatives are not readily available.

WHO now faces the double challenge of combating malaria while also upholding a commitment to reducing reliance on DDT. WHO proposes an eventual phase-out of DDT but expects that it will play a continued role in malaria control until effective alternatives are developed.

The organization Africa Fighting Malaria states that the current lack of investment from public and private sources for new public health insecticides makes the future of malaria eradication initiatives highly DDT-dependent. Despite efforts to find a vaccine against malaria, it will be difficult to phase-out DDT without phasing out this vital prevention aspect for people in need.

The EU, a Stockholm Convention signatory, recently passed regulations to limit the use of insecticides for agricultural use in the EU. With DDT banned as an agricultural product, remaining production would be on a smaller scale and at a higher price. Affected countries and international aid groups should consider the consequences of legislation regarding DDT and the potential to make DDT inaccessible and unaffordable for countries affected by malaria.

Don Roberts, a professor of tropical public health at the Uniformed Services University of the Health Sciences, recognizes this potential and urges a commitment to using DDT. He explains: “For years, the rich, developed nations that no longer have malaria have pressured tropical countries, which do, into giving up DDT. When countries stop using DDT, malaria spirals out of control.”

Given this trend, DDT should not be automatically discounted from discussions on prevention and eradication of malaria, but used effectively and with adequate precautions as part of a comprehensive strategy for malaria control. This includes, but is not limited to, usage of insecticide-treated bed nets, antimalarial drugs, environmental changes to destroy breeding grounds for mosquitoes, and strengthening health systems for public health. Although WHO encourages elimination of DDT by 2020, WHO also states that reductions in the use of DDT should be gradual and ensure that the level of transmission interruption is maintained.

DDT is not the only solution to eradicate malaria, but it should be part of a comprehensive plan to eradicate malaria with the same vigor that it was used to fight the disease in America and Europe. WHO states that every country in the world is now party to at least one human rights treaty that addresses health-related rights, including the Universal Declaration of Human Rights. Restricting access to this life-saving tool is a lost opportunity to impact child survival rates in the world’s poorest nations and to advocate for health as a human right. Phasing out DDT requires focus on integration and eventual elimination of the pesticide — not an abrupt halt. With more than 1 million people dying from malaria each year and over 2 million affected, considering safe and appropriate use of DDT merits attention.

Danielle Brown is currently employed by Management Sciences for Health and is a graduate of University of Virginia’s Master’s in Public Health program.