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Find video protocols related to scientific articles indexed in Pubmed.
Development of vaccines to prevent malaria in pregnant women: WHO MALVAC meeting report.
Expert Rev Vaccines
PUBLISHED: 09-17-2011
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The major public health consequences of malaria in pregnancy have long been acknowledged. However, further information is still required for development and implementation of a malaria vaccine specifically directed to prevent malaria in pregnant women and improve maternal, fetal and infant outcomes. The WHO Malaria Vaccine Advisory Committee (MALVAC) provides guidance to the WHO on strategic priorities and research needs for development of vaccines to prevent malaria. Here we summarize the discussions and conclusions of a MALVAC scientific forum meeting on considerations in the development of vaccines to prevent malaria in pregnant women. This report includes brief summaries of what is known, and major knowledge gaps in disease burden estimation, pathogenesis and immunity, and the challenges with current preventive strategies for malaria in pregnancy. We conclude with the formulation of a conceptual framework for research and development for vaccines to prevent malaria in pregnant women.
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Successful sporozoite challenge model in human volunteers with Plasmodium vivax strain derived from human donors.
Am. J. Trop. Med. Hyg.
PUBLISHED: 10-29-2009
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Successful establishment of a Plasmodium vivax sporozoite challenge model in humans is described. Eighteen healthy adult, malaria-naïve volunteers were randomly allocated to Groups A-C and exposed to 3 +/- 1, 6 +/- 1, and 9 +/- 1 bites of Anopheles albimanus mosquitoes infected with P. vivax, respectively. Seventeen volunteers developed signs and symptoms consistent with malaria, and geometric mean prepatent periods of 11.1 days (9.3-11) for Group A; 10.8 days (9.8-11.9) for Group B; and 10.6 days (8.7-12.4) for Group C, with no statistically significant difference among groups (Kruskal-Wallis, P = 0.70). One volunteer exposed to eight mosquito bites did not develop a parasitemia. No differences in parasite density were observed and all individuals successfully recovered after anti-malarial treatment. None of the volunteers developed parasite relapses within an 18-month follow-up. In conclusion, malaria-naive volunteers can be safely and reproducibly infected with bites of 2-10 An. albimanus mosquitoes carrying P. vivax sporozoites. This challenge method is suitable for vaccine and anti-malarial drug testing.
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Priorities in research and development of vaccines against Plasmodium vivax malaria.
Vaccine
PUBLISHED: 08-21-2009
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The WHO Initiative for Vaccine Research (IVR) Malaria Vaccine Advisory Committee (MALVAC) provides advice to WHO on priorities in malaria vaccine research and development (R&D). This document summarizes a MALVAC scientific consultation of leading vaccine scientists on priorities in Plasmodium vivax vaccine R&D. The meeting discussed recent advances and key challenges in addressing identified gaps in knowledge. Major areas of discussion included disease burden estimates, clinical disease spectrum definitions, potential target product profiles and immunological and clinical research needed to better inform antigen selection and vaccine design. The need for further development of the human challenge model for P. vivax vaccines and specific considerations for conduct of field trials with P. vivax vaccines was outlined. This report summarizes the discussion and conclusions of the consultation, with recommendations for priority targeted research.
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Comparison of immunogenicity of five MSP1-based malaria vaccine candidate antigens in rabbits.
Vaccine
PUBLISHED: 05-02-2009
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A number of laboratories around the world are producing Plasmodium falciparum erythrocyte-stage vaccine candidates in the pursuit of a vaccine against clinical malaria disease. These candidates are often based on the same parasite protein. Rigorous clinical development and testing of multiple candidates is limited by available resources, which underscores the need to conduct comparative studies of the different vaccine candidates. The purpose of this study was to compare five different candidate proteins all based on P. falciparum merozoite surface protein-1 (MSP1). After investigators submitted their candidates, basic protein profiles were evaluated in a blinded fashion by an independent laboratory, and groups of rabbits were immunized with the proteins. Sera obtained from the rabbits were compared for antibody titers by ELISA and for functional activity by an in vitro parasite growth inhibition assay (GIA) activity, again in a blinded fashion. In selected cases the fine specificity of the antibodies was assessed. Significant differences in immunogenicity as well as the functional activity of antibodies induced by the various vaccine candidates were noted. Data from this study can assist in making decisions for further clinical development of MSP1-based candidates, and this process sets a precedent for future comparisons of malaria vaccine candidates.
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MALVAC 2008: Measures of efficacy of malaria vaccines in phase 2b and phase 3 trials--scientific, regulatory and public health perspectives.
Vaccine
PUBLISHED: 03-13-2009
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The WHO Initiative for Vaccine Research and Global Malaria Programme convened a joint scientific forum in June 2008 to discuss scientific, regulatory and public health perspectives on the measurement of efficacy in malaria vaccine field efficacy trials. Participants included clinical trialists, statisticians and epidemiologists from both developed and developing countries, vaccine researchers and developers from academia and industry, and representatives of regulatory agencies. The efficacy of a vaccine against a disease is a summary indication of the extent to which those vaccinated are protected. However, there are several ways of measuring this and for high incidence diseases, such as malaria, in which there is variation in exposure and susceptibility from person to person, the choice of the appropriate measure of efficacy is more complex than is the case for low incidence diseases. There was agreement amongst statisticians at the meeting that basing analyses on "time to event" is the most appropriate method to analyse both incident infection and clinical malaria data from trials. However, policymakers would need to understand that this measure is different from that based on the proportion event-free up to a defined time, which has been used in reporting clinical challenge trials of malaria vaccines. For the assessment of public health impact, data should be reported on all episodes of malaria that a trial subject experiences, not only first episodes, and on duration of efficacy. Further research is required on the analysis of such multiple episode data. It will also be important to examine end-points such as severe malaria and death, though it may be difficult for the latter to be a primary end-point in trials. In order to compare findings in trials, it was suggested that efficacy estimates are reported at different time intervals after vaccination and that data sharing should be enhanced for all malaria vaccine clinical trials. It was appreciated that the epidemiology of malaria is changing in many settings and this may affect the public health benefit of a newly available malaria vaccine, whose likely impact would have to be assessed in the context of multiple other potential control measures. Research into possible interactions between malaria control measures was highlighted as a priority.
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Clinical trials to estimate the efficacy of preventive interventions against malaria in paediatric populations: a methodological review.
Malar. J.
PUBLISHED: 02-10-2009
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Recent years have seen publication of a considerable number of clinical trials of preventive interventions against clinical malaria in children. There has been variability in the specification of end-points, case definitions, analysis methods and reporting and the relative lack of standardization complicates the ability to make comparative evaluations between trials.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.