Antimalarial drugs resistance in Sudan

Mustafa Idris Elbashir, Ishag Adam

Abstract


Malaria is a major health problem in about 100 countries. More than 40% of the world population live in malaria endemic areas, and almost half of them in Sub-Saharan Africa where about 90% of the clinical cases occur. There are nearly 500 million clinical cases of malaria worldwide each year and 1.1 to 2.7 millions die annually, the majority of whom are children under 5 years in Africa (1, 2). Reduction of mortality from malaria depends on an accurate early diagnosis and a prompt effective drug treatment. Selection of an effective drug depends on knowledge of the antimalarial sensitivity profile of the P. falciparum isolates in an area (3). During the last 50 years, the development and spread of resistance to most front-line antimalarial drugs used in the prevention and treatment of the most severe form of human malaria has given reason for grave concern, which is greatly worsened by the reality that there are no available effective vaccines until now (4). Resistance of P. falciparum to most antimalarial drugs currently in use has been documented in almost all countries where there is transmission. This may be due to drug pressure, extensive use, and/or misuse, and Sudan is no exception (5,6).
Antimalarial drug resistance has been defined as the ability of a parasite strain to survive and/or multiply despite the administration and absorption of a drug given in doses equal to or higher than those usually recommended. The drug dose must be within tolerance of the subject, and the drug in question must gain access to the parasite or the infected red blood cell for the duration of the time necessary for its normal action (7).. Thus, a distinction between failure to clear malarial parasitemia or resolving of clinical disease following a treatment with antimalarial drug and true antimalarial drug resistance must be made. While drug resistance can cause treatment failure, not all treatment failure is due to drug resistance. The following factors can contribute to treatment failure: incorrect dosing, non-compliance with duration of dosing regimen, poor drug quality, drug interactions, poor absorption, and misdiagnosis. However, these factors may contribute to the development and intensification of true drug resistance through increasing the likelihood of exposure of the parasite to suboptimal drug levels.
In general, resistance appears to occur through spontaneous mutations that confer reduced sensitivity to a given drug or class of drugs. For some drugs, only a single point mutation is required to confer resistance, while for other drugs, multiple mutations appear to be required (8,9).
In this review article, we surveyed the available data on the situation of resistance for antimalarial drugs used in Sudan. We do believe that chloroquine resistance has reached a level that makes it necessary to stop its use as first line of treatment, at least for some time, and to adopt combination therapy as a policy for treatment of falciparum malaria in Sudan, as it is the current trend in most malaria endemic areas.

*Corresponding author: Department of Biochemistry, Faculty of Medicine, P.O. Box 102, Khartoum, Sudan. E-mail: mustidris@hotmail.com.


Full Text:

PDF

Refbacks

  • There are currently no refbacks.


ISSN: 1858-5345