Mosquitoes disease vectors

Meyers, J. L, M. Gray, and B. D. Foy. Mosquitocidal Properties of IgG Targeting the Glutamate-Gated Chloride Channel in Three Mosquito Disease Vectors (Diptera Culicidae). Journal of Experimental Biology 218(2015) 1487-95. 

Flies and mosquitoes are vectors for a number of other diseases that constitute significant menaces to public health, but we do not yet know what role chemical signals play in all of them. Where natural chemicals are important, much additional research will be essential to establish whether they offer realistic approaches to managing these afflictions. The results with leishmaniasis and African trypanosomiasis indicate that such research can both increase our understanding of how fly vectors live and also lead to practical measures for fighting the diseases they carry. 

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. 

Several species and populations from other Anopheles complexes have been discriminated based on CHC patterns. Examples include all five species of the An. quad-rimaculus complex (Carlson et al., 1997), some species of the An. maculipennis complex (Phillips et al., 1990a), malaria-vector and non-vector forms of the An. maculates complex (Kittayapong et al., 1990, 1993), and An. Stephensi strains susceptible or resistant to DDT and malathion (Anyanwu et al., 1993, 1997). CHCs have been used in combination with isoenzyme analysis to successfully differentiate populations of An. darlingi (Rosa-Freitas et al., 1992). All these findings demonstrate that hydrocarbon analysis is a powerful tool for distinguishing mosquito species and populations. This is particularly important for disease vectors, since it can facilitate interpretation of epidemiological data and assist implementation of control measures. 

Aldrin has been used as a soil insecticide to control root worms, beetles, and termites. Dieldrin has been used in agriculture for soil and seed treatment and in public health to control disease vectors such as mosquitoes and tsetse flies. Dieldrin also has had veterinary use as a sheep dip and has been used in the treatment of wood and mothproofing woolen products. Workers could be occupationally exposed to aldrin or dieldrin from inhalation and absorption through the skin. Most uses for aldrin and dieldrin were banned in 1975 since 1986, these compounds have not been produced or imported into the United States. 

A broad spectrum of diseases in children are known (or suspected) to be associated with unhealthy environments. For much of the world, traditional environmental health hazards continue to remain the primary source of ill-health. These include lack of adequate nutrition, poor sanitation, contaminated water, rampant disease vectors (e.g. mosquitoes and malaria), and unsafe waste disposal. In addition, rapid globalization and industrialization coupled with unsustainable patterns of production and consumption have released large quantities of chemical substances into the environment. Although the term environmental exposure can encompass a variety of factors, the focus of this document is specifically on environmental chemical exposures. Most of these substances have not been assessed for potential toxicity to children, nor have the most vulnerable subpopulations of children been identified. The incidence of a number of important paediatric diseases and disorders (e.g. asthma, neurobehavioural impairment) is increasing in several parts of the world. Although a variety of factors are likely to be involved, this may be due, in part, to the quality of the environment in which children live, grow, and play. 

Agrochemicals are used as indispensable ingredients to increase food production in sustainable agriculture. Environmental health chemicals are useful for control of disease vectors such as mosquitoes and other hazardous insects, for protection of people s healdi and safety, as well as for the inqirovement of the quality of life and die environment. It should be added that agrochemicals and environmental health chemicals have to be safe and eco-friendly in order to play dieir inqiortant roles appropriately. This is a requirement for materials that promote sustainable development. 

The value of insecticides in controlling human and animal diseases spread by insects has been dramatic. It has been shown that between 1942 and 1952, the use of DDT in pubHc health measures to control the mosquito vectors of malaria and the human body louse vector of typhus saved five million hves and prevented 100 million illnesses (4). Insecticides have provided the means to control such important human diseases as filariasis transmitted by Culex mosquitoes and onchocerciasis transmitted by Simulium blackflies. 

Triorganotin compounds have also been used experimentally in controUed-release formulations to control the infective snail vector in the debiHtating tropical disease schistosomiasis (biHiarzia) and to control mosquitoes in stagnant ponds (103). As yet, the large-scale use of such methods has Htfle support in the host third world countries where these problems are most severe. Tributyltin chloride has been used to confer rodent-repeUent properties on wine and cable coatings (104). 

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