22 research outputs found
High prevalence of dhfr triple mutant and correlation with high rates of sulphadoxine-pyrimethamine treatment failures in vivo in Gabonese children
Development of standardized laboratory methods and quality processes for a phase III study of the RTS, S/AS01 candidate malaria vaccine
BACKGROUND\ud
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A pivotal phase III study of the RTS,S/AS01 malaria candidate vaccine is ongoing in several research centres across Africa. The development and establishment of quality systems was a requirement for trial conduct to meet international regulatory standards, as well as providing an important capacity strengthening opportunity for study centres.\ud
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METHODS\ud
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Standardized laboratory methods and quality assurance processes were implemented at each of the study centres, facilitated by funding partners.\ud
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RESULTS\ud
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A robust protocol for determination of parasite density based on actual blood cell counts was set up in accordance with World Health Organization recommendations. Automated equipment including haematology and biochemistry analyzers were put in place with standard methods for bedside testing of glycaemia, base excess and lactacidaemia. Facilities for X-rays and basic microbiology testing were also provided or upgraded alongside health care infrastructure in some centres. External quality assurance assessment of all major laboratory methods was established and method qualification by each laboratory demonstrated. The resulting capacity strengthening has ensured laboratory evaluations are conducted locally to the high standards required in clinical trials.\ud
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CONCLUSION\ud
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Major efforts by study centres, together with support from collaborating parties, have allowed standardized methods and robust quality assurance processes to be put in place for the phase III evaluation of the RTS, S/AS01 malaria candidate vaccine. Extensive training programmes, coupled with continuous commitment from research centre staff, have been the key elements behind the successful implementation of quality processes. It is expected these activities will culminate in healthcare benefits for the subjects and communities participating in these trials.\ud
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TRIAL REGISTRATION\ud
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Clinicaltrials.gov NCT00866619
Intermittent screening and treatment versus intermittent preventive treatment of malaria in pregnancy: user acceptability
<p>Abstract</p> <p>Background</p> <p>Malaria in pregnancy is associated with increased risks of maternal and foetal complications. Currently, intermittent preventive treatment (IPT) of malaria during pregnancy with sulphadoxine-pyrimethamine (SP) is recommended by the WHO as part of a package of interventions also including insecticide-treated nets and effective case management. However, with increasing resistance to SP, the effectiveness of SP-IPT has been questioned. A randomized controlled trial (RCT) to investigate the relative efficacy of an alternative strategy of intermittent screening and treatment (IST), which involves a rapid diagnostic test for malaria at scheduled ANC visits and treatment of women only if positive, versus SP-IPT has been conducted in Ashanti region, Ghana. This paper reports on a complementary study investigating the acceptability of the different strategies to women enrolled in the trial.</p> <p>Methods</p> <p>Data were collected through twelve focus group discussions with women selected at random from the different arms of the RCT, exploring their experiences and perceptions about antenatal care and their involvement in the trial. Content analysis was used to identify relevant themes to structure the results.</p> <p>Results</p> <p>Five main themes emerged from participants' experiences of ANC and the RCT that would influence their acceptability of malaria prevention strategies during pregnancy: health benefits; drugs received; tests received; other services received; and health worker attitude. Their own health and that of their baby were strong motivations for attending ANC, and reported favourably as an outcome of being in the RCT. Women were not always clear on the biomedical function of drugs or blood tests but generally accepted them due to strong trust in the health staff. Home visits by staff and free ITNs as part of the trial were appreciated. Politeness and patience of health staff was a very strong positive factor.</p> <p>Conclusions</p> <p>Overall, both intermittent screening and treatment and intermittent preventive treatment appeared equally acceptable to pregnant women as strategies for the control of malaria in pregnancy. The women were more concerned about quality of services received, in particular the polite and patient attitude of health staff, and positive health implications for themselves and their babies than about the nature of the intervention.</p
Socio-economic status is inversely related to bed net use in Gabon
This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
Hemolysis Is Associated with Low Reticulocyte Production Index and Predicts Blood Transfusion in Severe Malarial Anemia
Background: Falciparum Malaria, an infectious disease caused by the apicomplexan parasite Plasmodium falciparum, is among the leading causes of death and morbidity attributable to infectious diseases worldwide. In Gabon, Central Africa, one out of four inpatients have severe malarial anemia (SMA), a life-threatening complication if left untreated. Emerging drug resistant parasites might aggravate the situation. This case control study investigates biomarkers of enhanced hemolysis in hospitalized children with either SMA or mild malaria (MM). Methods and Findings: Ninety-one children were included, thereof 39 SMA patients. Strict inclusion criteria were chosen to exclude other causes of anemia. At diagnosis, erythrophagocytosis (a direct marker for extravascular hemolysis, EVH) was enhanced in SMA compared to MM patients (5.0 arbitrary units (AU) (interquartile range (IR): 2.2–9.6) vs. 2.1 AU (IR: 1.3–3.9), p<0.01). Furthermore, indirect markers for EVH, (i.e. serum neopterin levels, spleen size enlargement and monocyte pigment) were significantly increased in SMA patients. Markers for erythrocyte ageing, such as CD35 (complement receptor 1), CD55 (decay acceleration factor) and phosphatidylserine exposure (annexin-V-binding) were investigated by flow cytometry. In SMA patients, levels of CD35 and CD55 on the red blood cell surface were decreased and erythrocyte removal markers were increased when compared to MM or reconvalescent patients. Additionally, intravascular hemolysis (IVH) was quantified using several indirect markers (LDH, alpha-HBDH, haptoglobin and hemopexin), which all showed elevated IVH in SMA. The presence of both IVH and EVH predicted the need for blood transfusion during antimalarial treatment (odds ratio 61.5, 95% confidence interval (CI): 8.9–427). Interestingly, this subpopulation is characterized by a significantly lowered reticulocyte production index (RPI, p<0.05). Conclusions: Our results show the multifactorial pathophysiology of SMA, whereby EVH and IVH play a particularly important role. We propose a model where removal of infected and non-infected erythrocytes of all ages (including reticulocytes) by EVH and IVH is a main mechanism of SMA. Further studies are underway to investigate the mechanism and extent of reticulocyte removal to identify possible interventions to reduce the risk of SMA development
Effectiveness and safety of artemether–lumefantrine versus artesunate–amodiaquine for unsupervised treatment of uncomplicated falciparum malaria in patients of all age groups in Nanoro, Burkina Faso: a randomized open label trial
The risk of malaria in Ghanaian infants born to women managed in pregnancy with intermittent screening and treatment for malaria or intermittent preventive treatment with sulfadoxine/pyrimethamine
Effectiveness of malaria control interventions in Madagascar: a nationwide case–control survey
Nationwide evaluation of malaria infections, morbidity, mortality, and coverage of malaria control interventions in Madagascar
Management of febrile children under five years in hospitals and health centres of rural Ghana.
BACKGROUND: The case management of febrile children in hospitals' and health centres' pre-roll out of the new WHO policy on parasitological diagnosis was assessed. The delivery of artemisinin combination therapy (ACT) at these two levels of the health system was compared. METHODS: Structured observations and exit interviews of 1,222 febrile children attending five hospitals and 861 attending ten health centres were conducted in six districts of the Brong Ahafo Region of Ghana. Effectiveness of delivery of case management of malaria was assessed. Proportions of children receiving ACT, anti-malarial monotherapy and antibiotics were described. Predictors of: a febrile child being given an ACT, a febrile child being given an antibiotic and of carers knowing how to correctly administer the ACT were assessed using logistic regression models stratified by hospitals and health centres. RESULTS: The system's effectiveness of delivering an ACT to febrile children diagnosed with malaria (parasitologically or clinically) was 31.4 and 42.4% in hospitals and health centres, respectively. The most ineffective process was that of ensuring that carers knew how to correctly administer the ACT. Overall 278 children who were not given an ACT were treated with anti-malarial monotherapy other than quinine. The majority of these children, 232/278 were given amodiaquine, 139 of these were children attending hospitals and 93 attending health centres. The cadre of health staff conducting consultation was a common predictor of the outcomes of interest. Presenting symptoms and examinations conducted were predictive of being given an ACT in hospitals and antibiotic in hospitals and health centres but not of being given an ACT in health centres. Treatment-seeking factors were predictive of being given an ACT if it was more than seven days since the fever began and an antibiotic in hospitals but not in health centres. CONCLUSION: Interventions to improve adherence to negative parasitological tests are needed, together with guidance on dispensing of antibiotics, but improving the education of carers on how to administer ACT will lead to the greatest immediate increase in the effectiveness of case management. Guidance is needed on implementation of the new test-based treatment for malaria policy in health facilities