The cause of the most lethal human malaria, chloroquine resistance is linked to multiple mutations in Pf CRT, a protein that likely functions as a transporter in the parasite’s digestive vacuole membrane. Rapid diagnostic assays for Pf CRT mutations are already employed as surveillance tools for drug resistance. Side effects of discontinuing plaquenil Plaquenil indication Oct 04, 2002 Recombinant clones expressing pfcrt alleles from the chloroquine-resistant lines Dd2, K76I, and 7G8 all had 50% inhibitory concentration IC 50 values in the range of 100 to 150 nM. These IC 50 values were typically 70 to 90% of those observed with the nontransformed chloroquine-resistant lines. Resistant P. vivax was not reported until 1989 in Papua New Guinea 9, although this species accounts for roughly as many cases of malaria as P. falciparum and was exposed to similar high levels of chloroquine pressure. Today, resistant P. vivax is present in several regions of Southeast Asia 10. The review highlights that chloroquine resistance has been underappreciated, with evidence for reduced susceptibility in many areas where vivax is endemic. Key findings of the review There was marked heterogeneity in the design of the clinical studies assessing the efficacy of chloroquine towards P. vivax. These studies suggest chloroquine resistance arose in ⩾4 distinct geographic foci and substantiate an important role of immunity in the outcomes of resistant infections after chloroquine treatment. Investigation of the resistance mechanisms and of the role of immunity in therapeutic outcomes will support new approaches to drugs that can take the place of chloroquine or augment its efficiency Early in the 20th century, intense demands for an effective quinine substitute launched the discovery and evaluation of a series of organic compounds (beginning with methylene blue), which led to pamaquine and quinacrine after World War I and ultimately produced chloroquine in 1934 [1, 2]. Here, we review recent field studies that support the central role of Pf CRT mutations in chloroquine resistance. Chloroquine resistant areas Update Chloroquine-Resistant Plasmodium falciparum -- Africa, Chloroquine-Resistant Malaria The Journal of Infectious Diseases. How to switch from plaquenil to methotrexateHydroxychloroquine and naproxenPlaquenil ms TRAVEL TO AREAS WITH CHLOROQUINE-RESISTANT MALARIA. Chloroquine-resistant P. falciparum is found in all parts of the world except the Caribbean and countries west of the Panama Canal. Although chloroquine-resistant P. falciparum predominates in Africa, it is found in combination with chloroquine-sensitive P. vivax malaria in South America and Asia. Malaria - Chapter 4 - 2020 Yellow Book Travelers' Health CDC. Chloroquine resistant Plasmodium vivax review Worldwide.. CDC - Malaria - Travelers - Malaria Information and.. Because of the danger of traveling to areas where chloroquine-resistant malaria is endemic, pregnant women should think twice before traveling to such areas as east Africa and Thailand. Chloroquine resistance was first reported in both South America and South East Asia in late 1950s. Since then chloroquine resistant strains have spread throughout the ranges where the conditions are favorable for the development of the parasite especially in the regions of sub-Saharan Africa 6. Mefloquine Lariam—This is the treatment of choice for travel to most regions of sub-Saharan Africa and other areas with high levels of chloroquine-resistant malaria parasites. Like chloroquine, the medication is taken once a week, from one to two weeks before departure until four weeks after your return.