highly efficient vector, a nonimmune population, and mining conditions that encouraged both vector breeding and malaria transmission fueled recurrent epidemics of malaria, which apparently started in the 1940s or early 1950s; 80% of the cases were P. falciparum. In 1955, public health authorities in Pailin began distributing chloroquine to workers daily; later, the frequency was reduced to twic...

Chloroquine began as a first-line antimalarial in 1946, the same year that the rock star Cher was born. Similar to Cher, chloroquine peaked in popularity in the early 1960s. Cher has famously made several major comebacks. Is it now chloroquine’s turn? For decades, chloroquine was a remarkably effective, safe, and inexpensive antimalarial. Optimism about effectiveness of chloroquine led public h...

Drug resistant strains of the malaria parasite, Plasmodium falciparum, have rendered chloroquine ineffective throughout much of the world. In parts of Africa and Asia, the coordinated shift from chloroquine to other drugs has resulted in the near disappearance of chloroquine-resistant (CQR) parasites from the population. Currently, there is no molecular explanation for this phenomenon. Herein, ...

Background. Antimalarial drug-resistant Plasmodium falciparum strains have been a major obstacle to the global efforts of controlling and eliminating malaria. The hope of reintroducing chloroquine for the treatment of uncomplicated malaria follows recent reports on decreases in the prevalence of chloroquine-resistant P. falciparum in several countries and recently, its total disappearance in Ma...

Most countries in resource-poor, malaria-endemic areas lack current and comprehensive information on antimalarial drug efficacy, resulting in sub-optimal antimalarial treatment policies. Many African countries continue to use chloroquine despite very high rates of resistance, and others have changed policies based on limited data, with mixed success. Methods for measuring antimalarial drug effi...

Genetic and biochemical research is providing new information on the mechanism of chloroquine resistance. Drug discovery initiatives are finding new leads that have favorable pharmaceutical properties and efficacy against chloroquine-resistant malaria.

BACKGROUND The predominance of chloroquine-susceptible falciparum malaria in Malawi more than a decade after chloroquine's withdrawal permits contemplation of re-introducing chloroquine for targeted uses. We aimed to compare the ability of different partner drugs to preserve chloroquine efficacy and prevent the re-emergence of resistance. METHODOLOGY/PRINCIPAL FINDINGS Children with uncomplic...

The spread of drug-resistant Plasmodium falciparum malaria has been a major impediment to malaria control and threatens prospects for elimination. We recently demonstrated the return of chloroquine-susceptible malaria in Malawi after chloroquine use was abandoned. In this study, we trace the origins of chloroquine-resistant and chloroquine-susceptible parasites in Malawi by sequencing the P. fa...