Limits...
Acquired resistance of malarial parasites against artemisinin-based drugs: social and economic impacts.

Porter-Kelley JM, Cofie J, Jean S, Brooks ME, Lassiter M, Mayer DG - Infect Drug Resist (2010)

Bottom Line: Artemisinin, a very effective yet expensive antimalarial, has quickly become the recommended drug of choice when all other possibilities fail.Resistance is developing to artemisinin while another effective antimalarial is not in sight.Moreover, the cost associated with preventing and containing the spread of antimalarial resistance is detrimental to economic progress.

View Article: PubMed Central - PubMed

Affiliation: Life Sciences Department, Winston-Salem State University, Winston Salem, NC, USA;

ABSTRACT
Malaria, a disease of poverty and high morbidity and mortality in the tropical world, has led to a worldwide search for control measures. To that end, good antimalarial chemotherapies have been difficult to find in the global market and those that seem to be most effective are rapidly becoming ineffective due to the emergence and spread of drug resistance. Artemisinin, a very effective yet expensive antimalarial, has quickly become the recommended drug of choice when all other possibilities fail. However, for all its promise as the next great antimalarial, the outlook is bleak. Resistance is developing to artemisinin while another effective antimalarial is not in sight. Malaria endemic areas which are mostly in developing countries must deal with the multifaceted process of changing and implementing new national malaria treatment guidelines. This requires complex interactions between several sectors of the affected society which in some cases take place within the context of political instability. Moreover, the cost associated with preventing and containing the spread of antimalarial resistance is detrimental to economic progress. This review addresses the impact of artemisinin resistance on the socioeconomic structure of malaria endemic countries.

No MeSH data available.


Related in: MedlinePlus

Chemical structure of artemisinin and derivatives. Diagram of artemisinin and its derivatives. 1, artemisinin; 2, artesunate; 3, artemether; 4, arteether; 5, dihydroartemisnin; 6, artelinic acid.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3108741&req=5

f1-idr-3-087: Chemical structure of artemisinin and derivatives. Diagram of artemisinin and its derivatives. 1, artemisinin; 2, artesunate; 3, artemether; 4, arteether; 5, dihydroartemisnin; 6, artelinic acid.

Mentions: Malaria, a mosquito-borne parasitic disease, affects 510 million people causing almost 3 million deaths annually.1 For more than 50 years, cinchona alkaloids and their derivatives were an integral part of malaria control. Indeed, chloroquine was one of the most effective synthetic antimalarial drugs ever produced. However, chloroquine-resistance falciparum malaria was first reported in South East Asia and South America and has now spread through Asia, Africa, and South America.2 This has led to a global resurgence of malaria. Currently, these alkaloids are being replaced by the terpene Artemisia annua, also known as qing hao or sweetworm, whose active ingredient is artemisinin. Discovered in 1971 by Chinese scientists, artemisinin was introduced to the world in 1979.3 Although quite expensive to produce, artemisinin is one of the most effective antimalarials. It is currently grown by farmers in China, Vietnam, and parts of Africa. With a long growing season, the process of extracting artemisinin from the leaves is complex and time consuming. Because of the difficulty in extracting it from the plant, a semi-synthetic version generated by the addition of chemical groups to extracted artemisinin is commonly used. Dihydroartemisinin (DHA) is the product of the first step; additional synthetic steps give rise to artesunate, artemether, and arteether which are metabolized back to dihydroartemisinin in the body (Figure 1). The artemisinin derivatives possess greater antimalarial properties. They are active against multiple drug-resistant parasites and have a very low level of toxicity to humans. As an antimalarial drug, artemisinin has a broad range of action against different stages of the parasite. It kills young circulating ring-stage parasites as well as the mature stages that sequester on blood vessels.3 Because of these properties, artemisinin is very useful in cases of severe malaria. Because of its broad range of action, dispensation of a single dose kills a large number of parasites. All the stages of the P. falciparum life cycle, including the gametocytes which transmit the infection to mosquitoes, are killed by artemisinin. Artemisinin is known to decrease the rate of gametocyte carriage and gametocyte density in a population.3–5


Acquired resistance of malarial parasites against artemisinin-based drugs: social and economic impacts.

Porter-Kelley JM, Cofie J, Jean S, Brooks ME, Lassiter M, Mayer DG - Infect Drug Resist (2010)

Chemical structure of artemisinin and derivatives. Diagram of artemisinin and its derivatives. 1, artemisinin; 2, artesunate; 3, artemether; 4, arteether; 5, dihydroartemisnin; 6, artelinic acid.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3108741&req=5

f1-idr-3-087: Chemical structure of artemisinin and derivatives. Diagram of artemisinin and its derivatives. 1, artemisinin; 2, artesunate; 3, artemether; 4, arteether; 5, dihydroartemisnin; 6, artelinic acid.
Mentions: Malaria, a mosquito-borne parasitic disease, affects 510 million people causing almost 3 million deaths annually.1 For more than 50 years, cinchona alkaloids and their derivatives were an integral part of malaria control. Indeed, chloroquine was one of the most effective synthetic antimalarial drugs ever produced. However, chloroquine-resistance falciparum malaria was first reported in South East Asia and South America and has now spread through Asia, Africa, and South America.2 This has led to a global resurgence of malaria. Currently, these alkaloids are being replaced by the terpene Artemisia annua, also known as qing hao or sweetworm, whose active ingredient is artemisinin. Discovered in 1971 by Chinese scientists, artemisinin was introduced to the world in 1979.3 Although quite expensive to produce, artemisinin is one of the most effective antimalarials. It is currently grown by farmers in China, Vietnam, and parts of Africa. With a long growing season, the process of extracting artemisinin from the leaves is complex and time consuming. Because of the difficulty in extracting it from the plant, a semi-synthetic version generated by the addition of chemical groups to extracted artemisinin is commonly used. Dihydroartemisinin (DHA) is the product of the first step; additional synthetic steps give rise to artesunate, artemether, and arteether which are metabolized back to dihydroartemisinin in the body (Figure 1). The artemisinin derivatives possess greater antimalarial properties. They are active against multiple drug-resistant parasites and have a very low level of toxicity to humans. As an antimalarial drug, artemisinin has a broad range of action against different stages of the parasite. It kills young circulating ring-stage parasites as well as the mature stages that sequester on blood vessels.3 Because of these properties, artemisinin is very useful in cases of severe malaria. Because of its broad range of action, dispensation of a single dose kills a large number of parasites. All the stages of the P. falciparum life cycle, including the gametocytes which transmit the infection to mosquitoes, are killed by artemisinin. Artemisinin is known to decrease the rate of gametocyte carriage and gametocyte density in a population.3–5

Bottom Line: Artemisinin, a very effective yet expensive antimalarial, has quickly become the recommended drug of choice when all other possibilities fail.Resistance is developing to artemisinin while another effective antimalarial is not in sight.Moreover, the cost associated with preventing and containing the spread of antimalarial resistance is detrimental to economic progress.

View Article: PubMed Central - PubMed

Affiliation: Life Sciences Department, Winston-Salem State University, Winston Salem, NC, USA;

ABSTRACT
Malaria, a disease of poverty and high morbidity and mortality in the tropical world, has led to a worldwide search for control measures. To that end, good antimalarial chemotherapies have been difficult to find in the global market and those that seem to be most effective are rapidly becoming ineffective due to the emergence and spread of drug resistance. Artemisinin, a very effective yet expensive antimalarial, has quickly become the recommended drug of choice when all other possibilities fail. However, for all its promise as the next great antimalarial, the outlook is bleak. Resistance is developing to artemisinin while another effective antimalarial is not in sight. Malaria endemic areas which are mostly in developing countries must deal with the multifaceted process of changing and implementing new national malaria treatment guidelines. This requires complex interactions between several sectors of the affected society which in some cases take place within the context of political instability. Moreover, the cost associated with preventing and containing the spread of antimalarial resistance is detrimental to economic progress. This review addresses the impact of artemisinin resistance on the socioeconomic structure of malaria endemic countries.

No MeSH data available.


Related in: MedlinePlus