Publication: Risk Associated with Asymptomatic Parasitaemia Occurring Post-Antimalarial Treatment
No Thumbnail Available
Published
2008
ISSN
1365-3156 (Electronic)
1360-2276 (Linking)
Date
2012-03-30
Editor(s)
Abstract
OBJECTIVE: Parasites may recur asymptomatically after initial clearance by antimalarial treatment. Current guidelines recommend treatment only when patients develop symptoms or at the end of follow-up. We wanted to assess prospectively the probability of becoming symptomatic and the risks of this practice. METHODS: We analysed data collected in 13 trials of uncomplicated paediatric malaria conducted in eight sub-Saharan African countries. These studies followed all cases of post-treatment asymptomatic parasitaemia until they developed symptoms or to the end of the 28-day follow-up period, at which time parasite genotypes were compared to pre-treatment isolates to distinguish between recrudescences and new infections. RESULTS: There were 425 asymptomatic recurrences after 2576 treatments with either chloroquine, sulfadoxine/pyrimethamine or amodiaquine, of which 225 occurred by day 14 and 200 between day 15 and day 28. By day 28, 42% developed fever (median time to fever = 5 days) and 30% remained parasitaemic but afebrile, while 23% cleared their parasites (outcome unknown in 4%). Young age, parasitaemia >/=500 parasites/microl; onset of parasitaemia after day 14, and treatment with amodiaquine were the main variables associated with higher risk of developing fever. CONCLUSION: In areas of moderate to intense transmission, asymptomatic recurrences of malaria after treatment carry a substantial risk of becoming ill within a few days and should be treated as discovered. Young children are at higher risk. The higher risk carried by cases occurring in the second half of follow-up may be explained by falling residual drug levels.
Link to Data Set
Associated content
Other publications in this report series
Journal
Journal Volume
Journal Issue
Citations
- Cited 19 times in Scopus (view citations)
Collections
Related items
Showing items related by metadata.
Publication Impact of Intermittent Screening and Treatment for Malaria among School Children in Kenya : A Cluster Randomized Trial(World Bank, Washington, DC, 2014-02)This paper investigates the effects of intermittent screening and treatment of malaria on the health and education of school children in an area of low-to-moderate malaria transmission. A cluster randomized trial was implemented with 5,233 children in 101 government primary schools on the south coast of Kenya in 2010-12. The intervention was delivered to children randomly selected from classes 1 and 5 who were followed up twice across 24 months. Once during each school term, public health workers used malaria rapid diagnostic tests to screen the children. Children who tested positive were treated with a six-dose regimen of artemether-lumefantrine. Given the nature of the intervention, the trial was not blinded. The primary outcomes were anemia and sustained attention and the secondary outcomes were malaria parasitaemia and educational achievement. The data were analyzed on an intention-to-treat basis. Anemia in this setting in Kenya, intermittent screening and treatment, as implemented in this study, is not effective in improving the health or education of school children. Possible reasons for the absence of an impact are the marked geographical heterogeneity in transmission, the rapid rate of reinfection following artemether-lumefantrine treatment, the variable reliability of malaria rapid diagnostic tests, and the relative contribution of malaria to the etiology of anemia in this setting.Publication Intensifying the Fight Against Malaria : The World Bank's Booster Program for Malaria Control in Africa(Washington, DC : World Bank, 2009)This document describes the purpose and context of the Booster Program, its first three years of operation and the proposed design of phase two of the program. Phase two seeks to build on the successes of and lessons learned from phase one and to enable the World Bank to play its expected role in scaling up and sustaining malaria control interventions to reach the new ambitious but achievable global goal set by the Roll Back Malaria (RBM) Partnership, of eliminating malaria as a major public health problem in Africa by 2015. The Bank has subscribed fully to this agenda, as illustrated by statements made by senior management in several public forums.Publication Impact of Malaria Control on the Demand for ACTs(World Bank, Washington, DC, 2008-06)As planning for malaria shifts from control to elimination and eventual eradication, policymakers are faced with decisions about resource allocation, and best approaches for financing malaria control interventions. At the operational level, these decisions will determine the relative emphasis on different tools such as insecticide treated nets (ITNs), indoor residual spraying (IRS) and artemisinin-based combinations (ACTs) in various local settings. At a global level, these decisions will guide the appropriate role of global financing mechanisms such as the Affordable Medicines Facility for Malaria (AMFm) in the malaria elimination effort. Previous papers have separately examined the cost-effectiveness of individual tools like IRS and ITNs and financing mechanisms such as the AMFm. Here we look at the cost-effectiveness of AMFm at different transmission intensities and levels of malaria control. We find that deaths averted as a result of AMFm are maximized when other control measures such as ITNs are simultaneously applied. Although policymakers have to tradeoff between investments in AMFm and malaria prevention tools, our results indicate strong synergies that get stronger as malaria control is amplified.Publication Pre-Referral Rectal Artesunate to Prevent Death and Disability in Severe Malaria : A Placebo-Controlled Trial(2009-02-14)BACKGROUND: Most malaria deaths occur in rural areas. Rapid progression from illness to death can be interrupted by prompt, effective medication. Antimalarial treatment cannot rescue terminally ill patients but could be effective if given earlier. If patients who cannot be treated orally are several hours from facilities for injections, rectal artesunate can be given before referral and acts rapidly on parasites. We investigated whether this intervention reduced mortality and permanent disability. METHODS: In Bangladesh, Ghana, and Tanzania, patients with suspected severe malaria who could not be treated orally were allocated randomly to a single artesunate (n=8954) or placebo (n=8872) suppository by taking the next numbered box, then referred to clinics at which injections could be given. Those with antimalarial injections or negative blood smears before randomisation were excluded, leaving 12 068 patients (6072 artesunate, 5996 placebo) for analysis. Primary endpoints were mortality, assessed 7-30 days later, and permanent disability, reassessed periodically. All investigators were masked to group assignment. Analysis was by intention to treat. This study is registered in all three countries, numbers ISRCTN83979018, 46343627, and 76987662. RESULTS: Mortality was 154 of 6072 artesunate versus 177 of 5996 placebo (2.5%vs 3.0%, p=0.1). Two versus 13 (0.03%vs 0.22%, p=0.0020) were permanently disabled; total dead or disabled: 156 versus 190 (2.6%vs 3.2%, p=0.0484). There was no reduction in early mortality (56 vs 51 deaths within 6 h; median 2 h). In patients reaching clinic within 6 h (median 3 h), pre-referral artesunate had no significant effect on death after 6 h or permanent disability (71/4450 [1.6%] vs 82/4426 [1.9%], risk ratio 0.86 [95% CI 0.63-1.18], p=0.35). In patients still not in clinic after more than 6 h, however, half were still not there after more than 15 h, and pre-referral rectal artesunate significantly reduced death or permanent disability (29/1566 [1.9%] vs 57/1519 [3.8%], risk ratio 0.49 [95% CI 0.32-0.77], p=0.0013). INTERPRETATION: If patients with severe malaria cannot be treated orally and access to injections will take several hours, a single inexpensive artesunate suppository at the time of referral substantially reduces the risk of death or permanent disability. FUNDING: UNICEF/UNDP/World Bank Special Programme for Research and Training in Tropical Diseases (WHO/TDR); WHO Global Malaria Programme (WHO/GMP); Sall Family Foundation; the European Union (QLRT-2000-01430); the UK Medical Research Council; USAID; Irish Aid; the Karolinska Institute; and the University of Oxford Clinical Trial Service Unit (CTSU).Publication Niger's HIV Response : Targeted Investments for a Healthy Future(World Bank, Washington, DC, 2014-06)The main objective of the study is to provide a comprehensive analysis of HIV and health financing needs, investment opportunities, and health system development in the context of the Government of Niger's HIV National Strategic Plan (NSP) 2013-17. The analysis provides support for HIV policy decision-making, investment scenarios and programmatic targeting and prioritization. In addition, the analysis helps Niger build the case for HIV and health impact investment including delivering estimates of health care savings as a result of these investments. The analysis was implemented by the World Bank in collaboration with UNAIDS from a request for analytical support from the Government of Niger. The study involved a desk review of HIV- and health-related evidence, epidemic trends and financial modeling. The Optima model (formerly Prevtool) was used to estimate optimal resource allocation during the NSP, and the impact and cost-effectiveness of past HIV investments. A financial commitment framework was used to estimate longer-term costs and savings of the HIV program and the fiscal dimension of HIV in Niger.
Users also downloaded
Showing related downloaded files
No results found.