SA’s Leading Malaria Researchers & Doctors Support the use of DDT to Control Malaria

South Africa’s leading malaria control experts, researchers and doctors support and endorse the use of the insecticide DDT to control malaria. Their statement is released in light of recent claims that DDT is harmful to human health and should be removed from South Africa’s malaria control programme.

In a media statement, researchers from, among others, South Africa’s Medical Research Council, National Health Laboratory Services and the World Health Organisation assert that since its introduction to disease control, DDT has been associated with improved human health and population growth, not the reverse.

In malaria control, Dichloro-Diphenyl-Trichloroethane (DDT) is sprayed in tiny quantities on the inside walls of houses and under the eaves of houses. It is highly effective at killing the female Anopheles mosquito that transmits malaria and has been used in South Africa since 1946. In 1996 South Africa removed DDT from its malaria control programme and the result was one of the worst malaria epidemics in the country’s history when hundreds of people lost their lives. The epidemic was subsequently controlled when DDT was reintroduced in 2000.

South Africa’s leading malaria researchers dismiss claims by University of Pretoria’s Professor Tiaan de Jager who recently claimed that DDT “descrambles the entire hormone system which does not only impact on reproductive health but on general health as well”. Richard Tren, director of health NGO Africa Fighting Malaria points out that the risks associated with malaria are far greater than any of the supposedly negative human health effects of DDT.

Says Tren, “the claims that DDT negatively affects reproductive health ring hollow when one considers that wherever it has been used mortality and morbidity have fallen and populations have grown.”

The researchers strongly support the South African Department of Health’s decision to use DDT as it is one of the most effective ways of controlling malaria, reducing death and disease and promoting good health.

Contact Information:

Richard Tren Africa Fighting Malaria

011 646 6750 082 921 1081

rtren@fightingmalaria.org

www.fightingmalaria.org

Statement on the use of DDT in malaria control

April 2004

In the light of recent media reports, we the undersigned, wish to support the use of DDT in indoor residual spraying programmes (IRS) in South Africa. Recent media attention has been focused on claims that DDT, when used in malaria control, negatively affects human reproductive health and general health. While we welcome the ongoing research into the use of DDT we feel that the publicity concerning the risks associated with DDT are disingenuous and misleads the public.

The Department of Health has used DDT highly effectively in malaria control since 1946. It is used in carefully controlled and scientifically monitored indoor residual spraying programmes in KwaZulu Natal, Mpumalanga and Limpopo Province. In South Africa, and indeed in numerous countries around the world, where DDT has been used in disease control, mortality and morbidity have fallen dramatically.

Professor Tiaan de Jager of the University of Pretoria maintains that DDT “descrambles the entire hormone system which does not only impact on reproductive health but on general health as well.[1]” Yet actual data from around the world contradicts this assertion. The association of DDT with reduced maternal deaths and infant mortality is a strong and consistent one. Additionally there is statistical coherence at all levels of DDT action to prevent contact between man and the Anopheles mosquito and to control malaria transmission. In just 2-3 years DDT spraying in Guyana reduced maternal deaths by 56% and infant mortality by 39%[2]. There was no offset of maternal and infant deaths due to adverse affects of DDT. The health improvements from DDT use were remarkable and accounted for 21 to 56% of increased population growth in Guyana during the post-war years[3]. In Sri Lanka, DDT use accounted for between 51 and 68% of rise in rate of population growth in the post-war period[4].

The advent of DDT use for disease control in the mid-1940s witnessed an unprecedented period of increased population growth, and this growth was greatest in those countries, including the United States, which used DDT to lift the burden of malaria from the backs of suffering populations. Without DDT, malaria has returned as a major health problem in many regions previously free of high infection rates. The causality is clear and unambiguous – DDT use in malaria control saves lives and improves human health, not the reverse.

DDT was removed from South Africa’s malaria control programme in 1996 for a number of reasons, among them environmentalist pressure and concern among residents that the insecticide leaves a white stain on their walls. However the development of insecticide resistance by Anopheles funestus mosquitoes to the synthetic pyrethroid insecticides that replaced DDT resulted in one of the most disastrous malaria epidemics in the country’s history. Between 1996 and 2000 the number of malaria cases in South Africa increased by over 450% and malaria mortality increased by almost 1000%[5].

In the face of the epidemic and based on sound scientific and medical advice, the South African Department of Health reintroduced DDT to the IRS programme. Within 1 year, malaria cases in KwaZulu Natal alone (the province worst hit by the epidemic) had fallen by around 80% and they continue to decline[6]. DDT was not reintroduced because the Department of Health, malaria control officers, scientists and malaria researchers were too dilatory or neglectful to find alternatives, but rather because it was the correct scientific and medical decision at the time.

No public health professional should object to scientific studies into DDT with regards to the human health effects of the insecticide. However given the unquestionable public health benefits that arise from DDT use, we wish to stress that claims made about the potential human health effects of DDT use in IRS programmes need to be placed in the context of the severe risks posed by malaria. Recent media attention has failed to do this and thereby misleads the public and undermines the country’s malaria control programmes. DDT has been used highly successfully to control malaria in South Africa and around the world and is responsible for saving millions of lives. In the absence of any proven actual human harm from the insecticide we continue to advocate for its use. We support any research into alternative methods for malaria control and for alternatives to DDT simply because this will strengthen any malaria control programme. However DDT has been and still is a crucially important tool for saving lives in South Africa and many other malarial countries.

We believe that the Department of Health is correct in its choice of DDT in its malaria control programme and as scientists, medical practitioners, and public health professionals endorse its use.

Signed: