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Haiti and the Dominican Republic, which share the island of Hispaniola, are the last locations in the Caribbean where malaria still persists. Malaria is an important public health concern in Haiti with 17,094 reported cases in 2014. Further, on January 12, 2010, a record earthquake devastated densely populated areas in Haiti including many healthcare and laboratory facilities. Weakened infrastructure provided fertile reservoirs for uncontrolled transmission of infectious pathogens. This situation results in unique challenges for malaria epidemiology and elimination efforts. To help Haiti achieve its malaria elimination goals by year 2020, the Laboratoire National de Santé Publique and Henry Ford Health System, in close collaboration with the Direction d’Épidémiologie, de Laboratoire et de Recherches and the Programme National de Contrôle de la Malaria, hosted a scientific meeting on “Elimination Strategies for Malaria in Haiti” on January 29-30, 2015 at the National Laboratory in Port-au-Prince, Haiti. The meeting brought together laboratory personnel, researchers, clinicians, academics, public health professionals, and other stakeholders to discuss main stakes and perspectives on malaria elimination. Several themes and recommendations emerged during discussions at this meeting. First, more information and research on malaria transmission in Haiti are needed including information from active surveillance of cases and vectors. Second, many healthcare personnel need additional training and critical resources on how to properly identify malaria cases so as to improve accurate and timely case reporting. Third, it is necessary to continue studies genotyping strains of Plasmodium falciparum in different sites with active transmission to evaluate for drug resistance and impacts on health. Fourth, elimination strategies outlined in this report will continue to incorporate use of primaquine in addition to chloroquine and active surveillance of cases. Elimination of malaria in Haiti will require collaborative multidisciplinary approaches, sound strategic planning, and strong ownership of strategies by the Haiti Ministère de la Santé Publique et de la Population.

Unless new strategies are deployed to combat malaria, the already enormous health and economic burden related to the disease in tropical countries is bound to worsen. The main obstacle to malaria control is the emergence of drug resistant strains of Plasmodium falciparum. As for HIV/AIDS and tuberculosis, the use of combinations of antimalarial drugs reduces the risk of selecting for resistant mutants of the plasmodial parasites. In large field trials, the combination of an artemisinin derivative and a partner drug with an unrelated mode of action (in this case mefloquine), has shown a remarkable double effect: preventing the emergence and spread of drug resistance, and interrupting the transmission of P. falciparum. This has opened the way for a new approach to the deployment of antimalarial drugs. Coupled with early detection and confirmed diagnosis, this strategy represents the only way forward in the chemotherapy of malaria. Massive economic assistance will be needed to detect and treat adequately the estimated 500 million cases of malaria per year, but without radical action there is no prospect of 'Rolling Back' malaria.

BACKGROUND: Artemisinin-based combination therapy (ACT) is the recommended first-line therapy for uncomplicated Plasmodium falciparum malaria worldwide but decreased artemisinin susceptibility, phenotypically characterized as slow parasite clearance time (PCT), has now been reported in Southeast Asia. This makes it all too important to measure the dynamics of parasite clearance in African patients treated with ACT over time, to understand trends and detect changes early enough to intervene METHODS: Individual patient data from 27 clinical trials of artesunate-amodiaquine (ASAQ) vs comparators conducted between 1999 and 2009 were analysed for parasite clearance on modified intent-to-treat (ITT) basis. RESULTS: Overall 15,017 patients treated for uncomplicated P. falciparum malaria at 44 sites in 20 sub-Saharan African countries were included in the analysis; 51% (n=7,660) vs 49% (n=7,357) were treated with ASAQ and comparator treatments, respectively. Seventy-seven per cent (77%) were children under six years of age. The proportion of the patients treated with ASAQ with persistent parasitaemia on Day 2 was 8.6%, and 1.5% on Day 3. Risk factor for not clearing parasites on Day 2 and Day 3 calculated by multivariate logistic regression with random effect on site and controlling for treatment were: high parasitaemia before treatment was (adjusted risk ratios (AOR) 2.12, 95% CI 1.91-2.35, AOR 2.43, 95% CI 1.98-3.00, respectively); non-ACT treatment (p=0.001, for all comparisons). Anaemia (p=0.001) was an additional factor for Day 2 and young age (p=0.005) for Day 3.In patients treated with ASAQ in studies who had complete parasitaemia data every 24 hours up to Day 3 and additionally Day 7, the parasite reduction ratio was 93.9% by Day 1 and 99.9% by Day 2. Using the median parasitaemia before treatment (p0=27,125 μL) and a fitted model, the predicted PCT (pPCT = 3.614*ln (p0) - 6.135, r(2) = 0.94) in ASAQ recipients was 31 hours. CONCLUSION: Within the period covered by these studies, rapid Plasmodium falciparum clearance continues to be achieved in Sub-Saharan African patients treated with ACT, and in particular with ASAQ. The prediction formula for parasite clearance time could be a pragmatic tool for studies with binary outcomes and once-daily sampling, both for research and monitoring purposes.

Background Malaria is reportedly receding in different epidemiological settings, but local long-term surveys are limited. At Mlomp dispensary in south-western Senegal, an area of moderate malaria transmission, year-round, clinically-suspected malaria was treated with monotherapy as per WHO and national policy in the 1990s. Since 2000, there has been a staggered deployment of artesunate-amodiaquine after parasitological confirmation; this was adopted nationally in 2006. Methods Data were extracted from clinic registers for the period between January 1996 and December 2010, analysed and modelled. Results Over the 15-year study period, the risk of malaria decreased about 32-times (from 0.4 to 0.012 episodes person-year), while anti-malarial treatments decreased 13-times (from 0.9 to 0.07 treatments person-year) and consultations for fever decreased 3-times (from 1.8 to 0.6 visits person-year). This was paralleled by changes in the age profile of malaria patients so that the risk of malaria is now almost uniformly distributed throughout life, while in the past malaria used to concern more children below 16 years of age. Conclusions This study provides direct evidence of malaria risk receding between 1996-2010 and becoming equal throughout life where transmission used to be moderate. Infection rates are no longer enough to sustain immunity. Temporally, this coincides with deploying artemisinin combinations on parasitological confirmation, but other contributing causes are unclear.

Background There are no data on the long term use of an artemisinin combination treatment in moderate or high transmission areas of Africa. Methods and findings Artesunate plus amodiaquine (AS+AQ) was used to treat slide-proven Plasmodium falciparum-infected patients of all ages in the Oussouye district, Casamance, Senegal, over a period of six years (2000 to 2005). Efficacy, by Kaplan Meier survival analysis (n = 966), and safety (adverse event rates, n = 752) were determined over 28 days. A weight-based dosing regimen was used for the loose tablets during 2000–2003 (n = 731) and a commercially available co-blister was used during 2004–2005 (n = 235). Annual crude (non PCR corrected) rates remained stable over the study period [range 88.5–96.7%; overall 94.6 (95% CI 92.9–95.9)]. Nine co-blister treated patients (0.9%) withdrew because of drug-related adverse events; seven had gastrointestinal complaints of whom two were hospitalized for vomiting. By Day 28, the mean total bilirubin (n = 72), AST (n = 94) and ALT (n = 95) values decreased. Three patients had Day 28 AST/ALT values > 40 < 200 IU/L. Changes in white cell counts were unremarkable (n = 87). Conclusion AS+AQ in combination was highly efficacious and well-tolerated in this area and justifies the decision to use it as first line treatment. Long-term monitoring of safety and efficacy should continue.