Molecular markers for surveillance of Plasmodium falciparum resistance to current antimalarials are sorely needed. A 28-day efficacy study of artemether-lumefantrine in eastern Sudan identified 5 treatment failures among 100 evaluable patients; 9 further individuals were parasite positive by PCR during follow-up. Polymorphisms in pfatpase6 and pfmdr1 were evaluated by DNA sequencing. One individual carried parasites with a novel pfmdr1 polymorphism (F1044L). pfmdr1 gene amplification in parasites prior to treatment occurred in three individuals who had recurrent infection during follow-up.

BackgroundIn areas of seasonal malaria transmission, treatment of asymptomatic carriers of malaria parasites, whose parasitaemia persists at low densities throughout the dry season, could be a useful strategy for malaria control. We carried out a randomized trial to compare two drug regimens for clearance of parasitaemia in order to identify the optimum regimen for use in mass drug administration in the dry season.Methodology and Principal FindingsA two-arm open-label randomized controlled trial was conducted during the dry season in an area of distinct seasonal malaria in two villages in Gedarif State in eastern Sudan. Participants were asymptomatic adults and children aged over 6 months, with low-density P. falciparum infection detected by PCR. Participants were randomized to receive artesunate/sulfadoxine-pyrimethamine (AS+SP) combination for three days with or without a dose of primaquine (PQ) on the fourth day. Parasitaemia detected by PCR on days 3, 7 and 14 after the start of treatment and gametocytes detected by RT-PCR on days 7 and 14 were then recorded. 104 individuals who had low density parasitaemia at screening were randomized and treated during the dry season. On day 7, 8.3% were positive by PCR in the AS+SP+PQ group and 6.5% in the AS+SP group (risk difference 1.8%, 95%CI −10.3% to +13.8%). At enrolment, 12% (12/100) were carrying gametocytes. This was reduced to 6.4% and 4.4% by day 14 (Risk difference 1.9% (95%CI −9.3% to +13.2%) in AS+SP+PQ and AS+SP groups, respectively.ConclusionAddition of primaquine to artemisinin combination treatment did not improve elimination of parasitaemia and prevention of gametocyte carriage in carriers with low-density parasitaemia in the dry season.Trial RegistrationClinicalTrials.gov NCT00330902

Background Since the World Health Organization recommended single low-dose (0.25mg/kg) primaquine (PQ) in combination with artemisinin-based combination therapies (ACTs) in areas of low transmission or artemisinin-resistant P. falciparum, several single-site studies have been conducted to assess its efficacy. Methods An individual patient meta-analysis to assess the gametocytocidal and transmission-blocking efficacy of PQ used in combination with different ACTs was conducted. Random effects logistic regression was used to quantify PQ effect on (i) gametocyte carriage in the first two weeks post-treatment; (ii) the probability of infecting at least one mosquito or of a mosquito becoming infected. Results In 2,574 participants from fourteen studies, PQ reduced PCR-determined gametocyte carriage on days 7 and 14, most apparently in patients presenting with gametocytaemia on day 0 (Odds Ratio (OR)=0.22; 95%CI 0.17-0.28 and OR=0.12; 95%CI 0.08–0.16, respectively). The rate of decline in gametocyte carriage was faster when PQ was combined with artemether-lumefantrine (AL) compared to dihydroartemisinin-piperaquine (DP) (p=0.010 for day 7). Addition of 0.25mg/kg PQ was associated with near complete prevention of transmission to mosquitoes. Conclusion Primaquine’s transmission-blocking effects are achieved with 0.25 mg/kg PQ. Gametocyte persistence and infectivity are lower when PQ is combined with AL compared to DP.

Background. Currently, mutations in rpoB, KatG, and rrs genes and inhA promoter were considered to be involved in conferring resistance to rifampicin, isoniazid, and streptomycin in Mycobacterium tuberculosis (MTB). Objective. The aims of this study were to detect the prevalence of first-line tuberculosis (TB) drug resistance among a group of previously treated and newly detected TB patients, to determine the association between prevalence of multidrug resistance (MDR) and demographic information (age and sex), to explain genes correlated with MDR Mycobacterium tuberculosis, and to characterize MTB via 16S ribosomal RNA (16S rRNA) analysis. Methods. A hundred MTB isolates from Sudanese pulmonary TB patients were included in the study. The proportional method of drug susceptibility test was carried out on Löwenstein-Jensen media. Multiplex PCR of rpoB and KatG genes and inhA promoter was conducted; then rrs genes were amplified by conventional PCR and were sequenced. The sequences of the PCR product were compared with known rrs gene sequences in the GenBank database by multiple sequence alignment tools. Result. The prevalence of MDR was 14.7% among old cases and 5.3% among newly diagnosed cases. Conclusion. Mutations in rrs could be considered as a diagnostic marker.

Background: Despite the importance of epidemiological studies in the development of effective control strategies and provision of basic health services for refugees and internally displaced persons (IDPs), data on the prevalence of malaria are limited. Thus, this study was conducted to estimate the molecular prevalence of malaria amongst the displaced population in Ardamata IDP camp in Al-Geneina City, Sudan. Methods: A cross-sectional study was conducted from July 2018 to December 2018 to estimate malaria prevalence amongst the displaced population in Ardamata IDP camp in Al-Geneina City, Sudan. A total of 380 patients with suspected malaria were recruited. Nested polymerase chain reaction (nPCR) assays were performed to detect the Plasmodium genus and species. Results: Of 380 patients, 232 (61.1%) were positive for malaria. Plasmodium falciparum was the only prevalent species detected amongst the study population. nPCR analysis revealed that none of the samples had Plasmodium vivax, Plasmodium ovale or Plasmodium malariae. The malaria prevalence rate was higher amongst males (67.1%) than in females (56.8%), and gender was the only risk factor that was significantly associated with malaria infection (p = .042). Conclusions: Despite control programmes, malaria remains a significant cause of illness amongst a displaced population. The high prevalence of malaria infection in this study indicates that additional health facilities and control strategies should be implemented in displaced camps and the surrounding areas.