Malaria control

Both DDT and chlordan are used in colorless, odorless, deobase-type solvent DDT in 5% solution and chlordan in 2% solution. The oil solvent is used because it is a nonconductor and because experience has shown that the crystals from a film of oil solvent solution adhere more firmly to the surface sprayed. A pressure-type spray tank, either a hand pump or mechanical source of air pressure, is used, with a special nozzle which gives a fan-shaped nonmisting spray. A special dripless valve is used. Several valves and nozzles which meet these requirements are on the market. The appropriate areas are sprayed with this fan-shaped painting spray stream, so that the surface glistens with the wet film but there is not sufficient quantity to run down. Experience has shown that this will leave approximately 200 mg. of DDT per square foot or an equivalent amount of chlordan. This procedure is recommended by the U. S. Public Health Service in its spraying technique for residences and food establishments treated in its program of spraying DDT only for malaria control. It has not as yet recommended chlordan for this use. Specifications for the sprayer nozzles procedure can be obtained from this source. 

Dondorp AM, Newton PN, Mayxay M, van Damme W, Smithuis FM, Yeung S et al. Fake antimalarials in Southeast Asia are a major impediment to malaria control cross sectional survey on the prevalence of fake antimalarials. Trop Med Int Health 2004 9( 12) 1241-6. 

Residual Sprays. It is possible to spray an oil solution containing 5% of DDT on the interior surfaces of a house and so deposit a residue of DDT crystals that will kill mosquitoes resting upon the treated area. This method of killing malaria carr3dng mosquitoes is especially valuable in malaria control. The mosquitoes rest on the interior walls or ceiling for several hours after feeding, and in so doing are destroyed and cannot bite the second time hence the spread of malaria is immediately stopped. 

Davidson (10) reported on the use of petroleum oil containing benzene hexachloride as a means of malaria control by adult mosquito destruction in western Africa. He concluded that an oil solution containing 0.5% of the gamma isomer of benzene hexachloride (Gammexane) sprayed on the inside wall surfaces of all houses at the rate of 10 mg. of gamma per square foot (2 quarts of solution to 1000 square feet) practically eliminated mosquitoes in those houses for about 6 months. 

U. S. Pub. Health Service and Tennessee Valley Authority, Malaria Control on Impoimded... 

India also used the pesticide to great effect. When India started its malaria-control program in 1953, almost the entire country was malarial, except for the mountainous areas, and there were, and still are, six different species of Anopheline mosquito vectors. Using DDT, India managed to bring the number of cases down from an estimated 75 million in 1951 to around 50,000 in 1961 and to reduce the annual mortality from malaria from about 800,000 to a few thousand. The achievement of reducing the number of infections to this degree cannot be overstated. India s success persists today because the country continues to use DDT. Reductions in malaria in many other countries were short-lived when they discontinued its use. 

Almost all the funding for the World Health Organization s (WHO) international strategy to eliminate malaria came from the United States. The U.S. contributed 17.5 million of the total 20.5 million budget of the WHO program between 1956 and 1965 all other countries combined contributed only 2.8 million. Independently of the WHO program, the U.S. Agency for International Development (USAID) spent 1.2 billion on its own malaria-control operations between 1950 and 1972. 

R. Tren, Economic Costs of Malaria in South Africa Malaria Control and the DDT Issue (1999). Available at http //www.iea.org.uk. 

DDT was probably harmful to wildlife when used in massive doses on cotton farms in the 1950s in America (although not so harmful as Carson and her followers made out), but it has never been proved to harm humans except those who tried to commit suicide with it. In any event, any harm to wildlife in America and Europe has been reversed. In contrast to its agricultural use, malaria control requires only that the insides of houses be sprayed used properly, little DDT is released into the environment. Yet myths persist about the harms it causes. Many Zambians think it causes male impotence. Most Westerners think it causes cancer. Nearly everyone forgets that only in massive doses can DDT cause problems. 

J. D., Maartens, F., Martin, C.L. and Barreto, A. (2007) Seven years of regional malaria control collaboration -Mozambique, South Africa, and Swaziland. Am J Trop Med Hyg, 76, 42-47. 

Propoxur [114-26-1], 2-isopropoxyphenyl IV-methylcarbamate (113) (mp 91°C, vp 0.84 mPa), is soluble in nonpolar solvents and in water to 2 g/L. The rat oral and dermal LD5Qs are 83 and >1000 mg/kg, respectively. Propoxur is used for the control of household insects, especially cockroaches, bedbugs, and mosquitoes, and is a replacement for DDT in malaria control. 

In the public health area, the phenomenal but short-lived successes of DDT in controlling disease vectors was noted. In 1955 the WHO had embarked on a program to eradicate malaria. However by the 70s it was evident that the resistance of anopheles to organochlorine pesticides had clearly foiled this plan. 1962 was a peak year for insecticide application in malaria control (130M DDT, 8M Dieldrin, and 1M Lindane). 

After 1983, the Standing Committee of State Council decided to stop the application of DDT in agriculture. Thereafter, DDT was mainly used as a raw material to produce Dicofol, with a small portion consumed as raw material to produce paints, as additives to produce mosquito-repellent incense, and to prevent malaria. The Chinese Center for Disease Control and Prevention (CDC) has decided that DDT can be used in closed systems and indoor sites in small amounts to control disease vectors, but its outdoor use is forbidden to prevent pollution. Malaria control in China has been effective, and DDT has not been used by local CDCs since 2001. The sale and consumption of DDT in 2001 and 2002 are shown in Table 3.4. It is seen that 83.9% of DDT produced was used to produce Dicofol 8.5% of that was exported for malaria prevention, 2.5% was used to produce mosquito-repellent incense, and 3.9% was used to produce paints. The investigation of consumption in 10 provinces and cities of China indicates that DDT is no longer used for agriculture or termite control, and a small portion of DDT is still used to prevent malaria. For example, 380 MT of DDT was used to control malaria between 1997 and 2000 in Yunnan province. 

A certain amount of DDT is exported from China. In total, 1834.8 MT of DDT was exported during 1998 2002, as shown in Table 3.5. There is no DDT imported to China. DDT was mainly exported to Africa and Southeast Asia. The exported DDT was mainly used for malaria control, and a small portion was used to antisepticize woods. 

In an interesting work in Farah, Mathura District, India, Dua et al. (1998) collected the skin lipids from face and blood from the occupationally exposed and unexposed volunteers and found that the levels of both HCHs and DDTs were higher in the samples obtained from the exposed group. They have also found an increase in the levels of both the compounds in Delhi population when compared with the data reported in previous publications on the concentrations in the adipose tissue collected a decade before in Delhi (Ramachandran et al., 1984) and several other parts of India (Kaphalia and Seth, 1983), reflecting the intensive use of these pesticides for malaria control in the sampling area. 

Raghavendra, K., Subbarao, S.K., 2002. Chemical pesticides in malaria control in India. ICMR Bulletin (ISBN 0337-4910) 32. 

Viswanathan, D.K., 1941. Experimental malaria control in a hyper-endemic tea garden in upper Assam by the use of pyrocide 20 as an insecticidal spray. J. Mai. Inst. India 4, 181. 

Ministry of Public Health of Thailand. 2003. Malaria control programme in Thailand. In ... 

Thiemann, 2002) were even higher than those reported a decade ago (Iwata et al., 1994). Although backgrounds of analytical methods and sampling locations are different among those studies, these observations suggest that the use of DDT for malaria control were relatively extensive until very recently in both northern and southern Vietnam. 

Although the use of DDT in agriculture was banned in 1974, this pesticide was officially used until the mid-1990s for eradication of Culex sp. and Anopheles sp., the main vector of malaria. In 1952, the government through the Department of Health introduced DDT and dieldrin for malaria control in Java Island. The formulation of DDT used was 75% WDP (Water Dispersable Powder) and it was applied two times a year at a dose of 2gm-2. From 1969 to 1974, 8,900,000 houses were sprayed with... 

Indonesia is also one of the few countries that produced DDT. In 1984, formulation plant of DDT was built with an annual capacity as much as 7000 tons year-1, and the main task was to supply all the DDT of needed by the Department of Health for malaria control program. The rest of the production only was permitted for export aimed to the countries that were using DDT for eradication of diseases, such as Latin America, and other Asian countries. The production was stopped in 1994, after the Department of Health banned the usage of DDT for health purposes. Currently, there is not enough information on the stockpile of these compounds available. 

Suroso, T., Sianturi, B., Pramono, B., 2000. Vector control policy in malaria control programme in Indonesia. Proceedings of Workshop on Sustainable Approaches for Pest and Vector Management and Opportunities for Collaboration in Replacing POPs Pesticides, Bangkok, March 6-10, 2000, UNEP/FAO/WHO. 

Hashim, M., 2003. Pesticides for malaria control. Paper presented at The Workshop on Development of National Implementation Plan for Malaysia, Kuala Lumpur, June 2003. 

World Health Organization (1993) Implementation of the global malaria control strategy. WHO Technical Report Series, No. 839. WHO Press. 

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