Background: After adoption of artesunate-amodiaquine (AS/AQ) as first-line therapy for the treatment of uncomplicated malaria by the malaria control programme, this study was designed to assess the availability of anti-malarial drugs, treatment practices and acceptability of the new protocol by health professionals, in the urban health facilities and drugstores of Yaoundé city, Cameroon.

BackgroundRegular monitoring of the levels of anti-malarial resistance of Plasmodium falciparum is an essential policy to adapt therapy and improve malaria control. This monitoring can be facilitated by using molecular tools, which are easier to implement than the classical determination of the resistance phenotype. In Cameroon, chloroquine (CQ), previously the first-line therapy for uncomplicated malaria was officially withdrawn in 2002 and replaced initially by amodiaquine (AQ) monotherapy. Then, artemisinin-based combination therapy (ACT), notably artesunate-amodiaquine (AS-AQ) or artemether-lumefantrine (AL), was gradually introduced in 2004. This situation raised the question of the evolution of P. falciparum resistance molecular markers in Yaoundé, a highly urbanized Cameroonian city.MethodsThe genotype of pfcrt 72 and 76 and pfmdr1 86 alleles and pfmdr1 copy number were determined using real-time PCR in 447 P. falciparum samples collected between 2005 and 2009.ResultsThis study showed a high prevalence of parasites with mutant pfcrt 76 (83%) and pfmdr1 86 (93%) codons. On the contrary, no mutations in the pfcrt 72 codon and no samples with duplication of the pfmdr1 gene were observed.ConclusionThe high prevalence of mutant pfcrt 76T and pfmdr1 86Y alleles might be due to the choice of alternative drugs (AQ and AS-AQ) known to select such genotypes. Mutant pfcrt 72 codon was not detected despite the prolonged use of AQ either as monotherapy or combined with artesunate. The absence of pfmdr1 multicopies suggests that AL would still remain efficient. The limited use of mefloquine or the predominance of mutant pfmdr1 86Y codon could explain the lack of pfmdr1 amplification. Indeed, this mutant codon is rarely associated with duplication of pfmdr1 gene. In Cameroon, the changes of therapeutic strategies and the simultaneous use of several formulations of ACT or other anti-malarials that are not officially recommended result in a complex selective pressure, rendering the prediction of the evolution of P. falciparum resistance difficult. This public health problem should lead to increased vigilance and regular monitoring.

The role of a rapid diagnostic test (RDT) in the case management of Plasmodium falciparum malaria infections has not been determined in Africa. Our study was conducted during November 2007-January 2008 to assess test accuracy of an RDT in the management of febrile outpatients in a peripheral urban health facility in Cameroon. We found the overall sensitivity to be 71.4% and a specificity of 82.2%; the positive predictive value and negative predictive value were 73.8% and 80.4%, respectively. False-negative and false-positive cases represented 11.8% and 10.5% of all febrile patients. Malaria alone (31.3%) was the first cause of fever; 33.5% of fever cases were of unknown origin. Acute respiratory infections were common among children 0-2 years of age (25.5%) and decreased with age. The risk of having a clinical failure with the presumptive treatment of febrile children was seven times greater than that of the RDT-oriented management (relative risk = 6.8, 95% confidence interval = 0.88-53.4, P = 0.03) because of the delay of appropriate treatment of non-malarial febrile illness. Our results suggest that the RDT may be of limited utility for children greater than five years of age and adults and that diagnosis based on microscopic examination of blood smears should be recommended for these patient populations, as well as in areas of low transmission.

Background: One year after the adoption of artesunate-amodiaquine (AS/AQ) as first-line therapy for the treatment of uncomplicated malaria, this study was designed to assess the treatment practices regarding anti-malarial drugs at health facilities in four rural areas in southern Cameroon.