View clinical trials related to Malaria.
Filter by:The scaling up of Long Lasting Insecticidal Nets (LLIN) and the expansion of Indoor Residual Spraying (IRS) has contributed to a significant decrease of malaria worldwide. However these control methods tackle only indoor and night biting vectors. The proportion of transmission occurring outdoors and before sleeping hours or so-called "residual transmission" is steadily increasing and may compromise the effort towards malaria elimination. The purpose of this study is to raise evidence on the effectiveness of mass use of topical repellents in addition to LLINs in controlling malaria infections. A multidisciplinary approach will be used to collect information on the most important factors that contribute to the successful reduction of "residual malaria transmission". In a first objective the epidemiological efficacy of repellents on prevalence of malaria carriers and malaria incidence will be assessed. To achieve this goal 98 communities will be randomly assigned to one of two treatment arms (LLIN and LLIN + repellent). Within a community a cross sectional random sample of 65 people will be drawn at the beginning and the end of the malaria season to obtain an estimate of the malaria prevalence. The second objective will handle the entomological efficacy and persistence of the topical repellent on malaria vectors. And lastly the acceptability, adherence and adequacy of the topical repellents will be studied in a third objective.
Pediatric cerebral malaria (CM) affects more than 3 million children each year killing ~20% and leaving one third of survivors with long term neurologic and psychiatric sequelae. Seizures occur commonly with CM and are associated with an increased risk of death and neuropsychiatric disabilities. In this Malawi-based, dose- escalation, safety and feasibility study of enteral levetiracetam in pediatric CM, the investigators will lay the groundwork for future efficacy studies aimed at improving seizure control and ultimately decreasing the neurologic morbidity of pediatric CM.
The main purpose of this study is to compare artesunate-mefloquine combination therapy given for 2 and 3 days at the same total dose for the treatment of uncomplicated falciparum malaria.
Many school children in Kenya are infected with plasmodia and helminth species and are at risk of coinfection. It has been suggested that the immune response evoked by helminth infections may modify immune responses to plasmodia species and consequently alter infection and disease risks. However, studies conducted to date have been typically cross-sectional and produced conflicting results, and there is a need for longitudinal studies to better understand the clinical consequences for individuals harbouring coinfection. This study aims to investigate the impact of intensive (once every 3 months) anthelminthic treatment versus annual treatment on the risk of clinical malaria and on immune responses among school children aged 5-14 years in Western Province. Specifically, this study aims to investigate the impact of intensive anthelminthic treatment on (i) the incidence of clinical malaria in school children, assessed using active case detection; (ii) the prevalence and density of Plasmodium spp. infection, using repeat cross-sectional surveys; and (iii) malaria and helminth specific immune responses. The study hypothesis is that intensive anthelminthic treatment among children infected with either Ascaris lumbricoides or hookworm modifies human host immune responses to plasmodia and helminth infections, and therefore alters the risk of Plasmodium infection and clinical disease. This individually randomised trial will recruit 1,450 children aged 5-14 years found to be infected with either Ascaris lumbricoides or hookworm species. Recruited children will be randomized to receive albendazole treatment either every three months or annually and monitored through periodic surveillance for clinical malaria episodes over 18 months. In addition, blood samples will be collected from sub-sample of children and screened for malaria specific immunoglobulin (Ig)G1 and IgG3 and helminth specific IgE, IgG2, IgG4 and IgM. Cell culture supernatants will be assayed for interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-10, IL-5, IL-4 and IL-2.
Malaria transmission is falling in some parts of Africa as bed nets and anti-malarials become more widely available. However, transmission still persists and it appears that additional control measures are required. The leading malaria vaccine candidate in development is RTS,S which has efficacy against clinical malaria measured at 30-50% in the field. This partial protection might be enhanced by combination with other components. The other vaccination approach that has produced repeatable efficacy in humans is the use of viral vectors to induce T cell responses. Previous attempts with this vaccine approach have been effective in challenge studies in Oxford, but ineffective in the field, probably because of reduced immunogenicity with previous vector platforms. Recently, studies in Oxford, Kenya and the Gambia have shown higher levels of immunogenicity by using a chimpanzee adenovirus (ChAd63) followed by an attenuated vaccinia virus (modified vaccinia Ankara) to deliver the pre-erythrocytic antigen, multiple epitope string with thrombospondin- related adhesion protein (ME-TRAP). The increase in immunogenicity has lead to sterile protection in 3 out of 14 volunteers and partial protection in 5 out of 14 volunteers in challenge studies. The investigators propose a Phase 2b study of 120 healthy adult men in Senegal. The investigators will assess the efficacy and further evaluate the immunogenicity and safety profile of the vaccine regimen. The investigators also intend to assess the correlates of efficacy and natural immunity.
The purpose of this study is to assess the feasibility and impact of introducing subsidized malaria rapid diagnostic tests (RDTs) into retail sector drug shops in Uganda. This is a randomized controlled trial at the village level, taking place in 6 districts in Eastern Uganda. Licensed drug shops in selected villages were trained in proper RDT storage, administration, interpretation and disposal and were given access to subsidized RDTs for sale. This study explores whether drug shop owners--when given access to training and subsidized RDTs--will choose to promote and sell RDTs to customers and, if so, at what volume and what price. The investigators also explore whether shops will safely store, administer, interpret and dispose of RDTs and to what extent they will use RDT results to guide treatment recommendations. Finally, the study explores whether making RDTs available for sale in local drug shops has a community level impact on diagnostic testing and appropriate treatment for malaria.
In areas of Africa where malaria is only a problem during a short rainy season, monthly courses of antimalarial drugs can provide very effective prevention of malaria in children. This approach, called intermittent preventive treatment in children (IPTc) but now known as Seasonal Malaria Chemoprevention (SMC), may also be useful in large areas of Africa where malaria is transmitted for longer each year. It is uncertain if IPTc would be effective, acceptable to communities or sustainable when delivered over a longer period, but this is an important public health question of key interest to policy makers, because in areas with a longer transmission season, the burden of malaria is typically higher than in highly seasonal areas. Another form of prevention that would be operationally easier for African countries to put into practice would be to treat malaria patients with long-lasting antimalarials, which protect children against further malaria episodes for several weeks. Because malaria disproportionately affects certain high risk children more than others, causing repeated attacks of fever and leading to severe anaemia, long-acting drugs may be a simple and effective way to target limited resources at the individuals who most need protection. This may be particularly beneficial where malaria is a seasonal problem, because repeated malaria attacks will not only be borne by a few unfortunate children, but will also occur close together in time. The investigators propose a clinical trial to evaluate these two forms of chemoprevention in Kumasi, Ghana, an area with an extended malaria transmission season. Children under 5 years of age currently have access to diagnosis and treatment of malaria via by community based health workers. Children enrolled in the study will receive either the standard community-based diagnosis and treatment, treatment with a longer-acting artemisinin combination therapy (ACT), or standard care plus five monthly courses of seasonal malaria chemoprevention (SMC) during the peak in transmission.
Blackwater fever, characterized by intravascular haemolysis and hemoglobinuria, is an important cause of renal impairment and mortality in severe malaria caused by Plasmodium falciparum. The largest malaria clinical trials report blackwater incidences of 5-7% in Asian adults and 4% in African children with severe malaria treated with artesunate or quinine. The prevalence of blackwater fever in Chittagong, Bangladesh is 15% with associated rates of renal failure and mortality of 42.9% and 14.2% respectively. The fundamental characteristic of blackwater fever is the presence of intravascular hemolysis of both infected and uninfected erythrocytes and release of free haemoglobin. The cytotoxic free haemoglobin present can cause severe oxidative damage as a result of haem redox cycling yielding ferric and ferryl heme, which generate radical species that induce lipid peroxidation and subsequent production of F2-isoprostanes (F2-IsoPs). Evidence suggests that F2-IsoPs generated by the hemoprotein-catalyzed oxidation of lipids are responsible for the oxidative damage and vasoconstriction associated with renal injury in haemolytic disorders and rhabdomyolysis. A novel mechanism of paracetamol was recently demonstrated, showing that paracetamol is a potent inhibitor of hemoprotein-catalyzed lipid peroxidation by reducing ferryl heme to its less toxic ferric state and quenching globin radicals. In a recent proof of concept trial, paracetamol at therapeutic levels was shown to significantly decrease oxidant kidney injury, improve renal function and reduce renal damage by inhibiting the hemoprotein-catalyzed lipid peroxidation in a rat model of rhabdomyolysis-induced renal injury. Since adults with severe malaria demonstrate increased concentrations of cell-free haemoglobin, and urinary F2-IsoPs, the investigators hypothesize that this novel inhibitory mechanism of paracetamol may provide renal protection in this population by reducing the hemoprotein-induced lipid peroxidation. As there is currently no consensus that exists concerning adequate medical treatment for blackwater fever, the potential application of this safe and extensively used drug would be of great benefit.
Prime boost vaccination with ChAd63 ME-TRAP followed eight weeks later with MVA ME-TRAP shows efficacy against malaria infection when tested in UK volunteers using sporozoite challenge experiments. It is a leading candidate vaccination strategy against malaria. In the field, Phase I studies have been conducted in adults in Kenya and The Gambia and children and infants in The Gambia. The vaccination strategy appears safe and well tolerated in these populations, and also shows impressive immunogenicity, not significantly different to that seen in the UK trials where efficacy was shown. In particular, recent data from The Gambia shows excellent safety and immunogenicity in infants in malaria endemic areas, who would be the ones to benefit most from such a vaccine against malaria. With this clinical development as background, the investigators now propose to evaluate efficacy against natural malaria infection in this important target group for an effective malaria vaccine, that is, 5-17 month infants and children living in malaria endemic areas. The proposed study area, Banfora, Burkina Faso, is highly endemic for Plasmodium falciparum malaria.
An effective vaccine against malaria is urgently needed to combat the scourge of this disease. Before candidate vaccines can be tested in endemic countries, they are first tested in human volunteers in so-called Controlled Human Malaria Infections (CHMI's). Ideally, a candidate vaccine should be tested against multiple strains of malaria, representative of the disease's global distribution. To date, however, only one such strain (NF54) has been broadly used in CHMI's. The purpose of this study is to compare the course of infections with 2 novel malaria strains to those with NF54 in human volunteers.