Nearly half a billion people are infected with malaria each year and more than a million people die from this disease. Malaria is transmitted through the bite of a female Anopheles mosquito infected with malaria parasites. When the parasites enter the human body, it slowly destroys the body’s red blood cells, eventually killing the patient if left without undergoing immediate treatment (Stanmeyer 2007). One of the means employed to counter the spread of malaria is through the use of DDT as an insecticide to kill the mosquitoes before they are able to infect more people.
DDT is an organochlorine insecticide that is absorbed through surface contact and kills by poisoning the nervous system (Pesticide Action Network UK 2012). It has become highly effective in combating insect-borne human diseases among military and civilian populations (U.S. Environmental Protection Agency 2011). Currently, through the Stockholm Convention, which was signed during the United Nations Environment Programme 2002, 12 chemicals have been banned, one of which is DDT. However, production and usage was granted to control disease vectors provided recommendations and guidelines of the World Health Organisation (WHO) were adhered to, until locally safe, effective and affordable alternatives were available (van den Berg 2009). Thus, this study is to investigate the effectiveness of the usage of DDT to combat malaria and addresses the controversies surrounding this method by looking at how it affects humans and the environment.
1. Benefits of using DDT
Can be used indoors for the prevention of mosquito breeding as wettable DDT powder can be mixed in water. This mixture is then sprayed through a compressed air sprayer and not applied as an aerosol. In Zimbabwe, the spraying crews apply about 2 grams of pesticide per square yard of surface, leaving a light white coating of pesticide powder. It is active in repelling malaria carrying mosquitoes for up to a year (Maykuth 2000). Furthermore, applied DDT is long lasting so only small amounts are needed to sustain protection for one house hold.
In addition, DDT is a cheap form of pesticide available on the market. This is obvious through detailed calculations and recent price quotes from manufacturers and WHO suppliers for DDT and nine other insecticides commonly used in similar malaria control programmes, it is shown that DDT is still the cheapest insecticide on a cost per house basis (Walker 2000). Combining both facts that the pricing of DDT is cheap and that only small amounts are used each time and at long intervals, DDT has turned out to be a cost effective insecticide to be used to combat malaria in poor countries whose government is unable to afford more expensive alternatives.
Furthermore, DDT is also effective against mosquitoes which are resistant to some other insecticides. As this chemical repels mosquitoes from areas where it has been applied, is a moderate irritant and has toxic properties,...