TREATMENT, CONTROL & PREVENTION OF MALARIA

The bite of an infected female Anopheles mosquito is required for the transmission of the Plasmodium parasite that causes malaria, thus preventing the bite of this mosquito will help to prevent the acquisition and transmission of the disease. There have been several reported cases of resistance of malaria parasites to some available antimalarial drugs even though artemisinin-based combination therapy (ACT) is still the drug of choice for malaria treatment. However, the treatment of malaria infection usually involves a series of combination therapy that incorporates one antimalarial agent and another as a way of fighting the resistance of the parasite while ensuring a better prognosis in the patient taking the medication.

There are usually some variations in the treatment of malaria infection depending on the region where the infection occurred and the prevalent Plasmodium parasite in that geographical area. Thus, there abound certain national guidelines and measures adopted for the effective treatment of the disease depending on the endemicity of the disease in the region. Malaria chemotherapy usually involves the use of Artemisinin-related compounds (artesunate, artemether, and artemisinin), Quinolone-related compounds (mefloquine, chloroquine, primaquine, and quinine), Anti-folates (trimethoprim, pyrimethamine, and proguanil), and certain Antibacterial agents such as macrolides, tetracyclines, and sulphonamides which are used in combination with antimalarial drugs when malaria therapy is anticipated. Chloroquine (which was among the first antimalarial agent), which can be administered either orally or parenterally still remains the preferred drug option for all forms of malaria infection except for certain stages of P. falciparum malaria infection.

Some antimalarial drugs are contraindicated in pregnancy and even in some disease condition (cardiac disorders and disorders of the renal system), thus malaria treatment in pregnant women should be undertaken with caution to prevent fatality in the foetus or mother. Antimalarial agents that functions as folate-antagonists (proguanil) helps to block the synthesis of folate (folic acid) in Plasmodium parasites, which is an important process required by the parasite to thrive. Plasmodium parasites are incapable of utilizing pyrimidines from their human host, thus an obstruction of their innate folate synthesis machinery will automatically result to cell death due to a reduction in pyrimidines and other nitrogenous bases required for synthesis of the organism’s nucleic acid.

Artemisinin-related agents are a class of drugs which were originally sourced from a Chinese herbal plant called Artemisia annua (Qinghaosu); and these drugs have been found to be effective to the different forms of malaria infection including multidrug-resistant P. falciparum malaria infection. Quinolone-related compounds (quinine) used for the treatment of malaria infection are alkaloids sourced from the bark of Cinchona tree, and they have been found to be effective against P. falciparum infection. Sulphonamides and other antibacterial agents administered in combination with other antimalarial drugs are used as prophylactics and also for the treatment of P. falciparum malaria infection. These agents usually act as folate-antagonist, as they inhibit the synthesis of folic acid by the Plasmodium parasite.

PREVENTIVE AND CONTROL MEASURES FOR MALARIA

Malaria should be controlled and prevented in human populations (especially in the subtropics and tropical regions where its dominance is evident) due to the economic and medical consequences and burden of the disease. It is a life-threatening parasitic infection that requires complete cure. Controlling malaria infection will help to reduce the morbidity and mortality due to the disease; improve mans activities; reduce and channel resources spent on malaria treatment for other useful ventures, and most of all, it will ensure a better life and future for the present and future generations of individuals in malaria endemic regions. A reduction in malaria morbidity and mortality especially amongst high-risk groups for example pregnant women, breastfeeding mothers, and children through adequate and sustainable containment of the transmission of the disease through the bite of female Anopheles mosquito is critical in malaria endemic regions.

However, the world through its many malaria control and eradication programs such as the Roll Back Malaria (RBM) Programme and the rest are looking at a total eradication of the disease in those parts of the world where malaria still accounts for a high rate of morbidity and mortality amongst high-risk groups. The use of artemisinin-based combination therapy (ACT) in addition to the protection of women with intermittent preventive treatment during pregnancy (IPTp) has helped to reduce the health and economic menace of the disease in African continent. Also, the use of long-lasting insecticide-treated mosquito nets (LLITNs) and indoor residual spraying (IRS) using potent insecticides have also been recommended as preventive and control measures for the disease.

Malaria is a widespread mosquito-borne disease caused by Plasmodium parasite which is transmitted through the bite of an infected mosquito. The disease is among the leading cause of death in the tropic and subtropical parts of the world; and its prevention is dependent upon strict personal hygiene, effective chemotherapy and a holistic public health measures towards the disease. Malaria disease which already has enormous negative impact on humanity should be prevented and controlled as much as possible in order to ensure better health for people in malaria endemic countries. The total prevention and control of malaria in the subtropics and tropical counties of the world is still a mirage. Eradication of both the Plasmodium parasite and its insect vector in these areas has been very much slower.

The control and prevention of malaria depends hugely on the total elimination of possible breeding sites of the insect vector (female Anopheles mosquito) and avoidance of long biting contact between human hosts and the insect vector. The resistance of the Plasmodium parasite to readily available antimalarial drugs coupled with the prevailing resistance of the insect vector to insecticides have further compounded the established control measures for the disease in affected parts of the world. Malaria is a vector-borne disease that is transmitted from person to person through the female Anopheles mosquito; thus, protecting people from the insect vector (female Anopheles mosquito) and reducing the number of insect vectors in human populations/environment will go a long way in helping to stop the spread of the disease.

There is still no vaccine against the disease; nevertheless, frantic efforts to develop an effective malaria vaccine are still in progress and very promising. Also, existing malaria control and preventive efforts (including the use of LLITNs, IRS, and IPTp) in malaria endemic regions are beginning to show promising results in some countries, and this has helped to lower the morbidity and mortality associated with the disease in these areas. There are significant variations amongst countries that use LLITNs as a malaria control measure. The reason that may be attributed to the poor distribution or usage of LLITNs in malaria endemic countries in Africa may be connected to paucity of resources to make these nets available for use.

In some cases, some people may have it but still do not appreciate the importance of sleeping under the nets, and thus will resort to not using them at all. Whatever maybe the reason for the non-usage of LLITNs by children in some malaria endemic regions of Africa as depicted in the figure below, advocacy and education is a vital tool to convincing these people to the benefit of using these nets as one of the ways to be malaria free. Resources should be channeled towards research and development (R&D) in malaria endemic countries in order to develop novel ways of fighting the disease so that the world’s target of completely eradicating malaria can be achieved.

OTHER PREVENTIVE AND CONTROL MEASURES FOR MALARIA

  • Ensuring regular and effective insecticide spraying around homes and other mosquito breeding sites in order to destroy the insect vectors.
  • Constant drainage of swamps and possible destruction or elimination of other breeding sites of the mosquito’s habitats.
  • Avoiding mosquito bites by wearing long clothes to cover the whole body when in endemic areas, use of long lasting insecticide treated mosquito nets and use of mosquito nettings on doors and windows of houses to prevent the invasion of the insect vector.
  • Drainage of breeding sites such as gutters to remove surface waters and filling of ponds and pot-holes with sands to prevent breeding of the insect vector.
  • Use of effective anti-malarial drugs to treat patients during an infection in order to break the life cycle of the Plasmodium
  • Proper funding of preventive programs (such as the Roll Back Malaria Initiative of the WHO) in endemic areas couple with the stepping up of research developments of malaria vaccine and a lasting cure or treatment to the malady is also vital to the termination of the disease.
  • Local research in malaria endemic areas should be strengthened as a way of finding a lasting solution to the malaria endemicity.
  • People travelling to malaria endemic areas should avoid mosquito bites as much as possible by sleeping under long lasting insecticide treated nets and covering the body properly when outdoor.

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