Current malaria elimination guidelines are based on the concept that malaria transmission becomes heterogeneous in the later phases of malaria elimination [1]. In the pre-elimination and elimination phases, interventions have to be targeted to entire villages or towns with higher malaria incidence until only individual episodes of malaria remain and become the centre of attention [1]. With increasing evidence of clustering of malaria episodes within villages, we argue that there is an intermediate step. Heterogeneity in malaria transmission within villages is present long before areas enter the pre-elimination phase, and identifying and targeting hotspots of malaria transmission should form the cornerstone of both successful malaria control and malaria elimination. [Read more…]
A Research Agenda for Malaria Eradication: Vector Control
Abstract: Different challenges are presented by the variety of malaria transmission environments present in the world today. In each setting, improved control for reduction of morbidity is a necessary first step towards the long-range goal of malaria eradication and a priority for regions where the disease burden is high.
For many geographic areas where transmission rates are low to moderate, sustained and well-managed application of currently available tools may be sufficient to achieve local elimination. The research needs for these areas will be to sustain and perhaps improve the effectiveness of currently available tools. For other low-to-moderate transmission regions, notably areas where the vectors exhibit behaviours such as outdoor feeding and resting that are not well targeted by current strategies, new interventions that target predictable features of the biology/ecologies of the local vectors will be required. [Read more…]
A Research Agenda for Malaria Eradication: Drugs
Abstract: Antimalarial drugs will be essential tools at all stages of malaria elimination along the path towards eradication, including the early control or “attack” phase to drive down transmission and the later stages of maintaining interruption of transmission, preventing reintroduction of malaria, and eliminating the last residual foci of infection.Drugs will continue to be used to treat acute malaria illness and prevent complications in vulnerable groups, but better drugs are needed for elimination-specific indications such as mass treatment, curing asymptomatic infections, curing relapsing liver stages, and preventing transmission. [Read more…]
A Research Agenda for Malaria Eradication: Vaccines
Abstract: Vaccines could be a crucial component of efforts to eradicate malaria. Current attempts to develop malaria vaccines are primarily focused on Plasmodium falciparum and are directed towards reducing morbidity and mortality. Continued support for these efforts is essential, but if malaria vaccines are to be used as part of a repertoire of tools for elimination or eradication of malaria, they will need to have an impact on malaria transmission.
We introduce the concept of “vaccines that interrupt malaria transmission” (VIMT), which includes not only “classical” transmission-blocking vaccines that target the sexual and mosquito stages but also pre-erythrocytic and asexual stage vaccines that have an effect on transmission. VIMT may also include vaccines that target the vector to disrupt parasite development in the mosquito. Importantly, if eradication is to be achieved, malaria vaccine development efforts will need to target other malaria parasite species, especially Plasmodium vivax, where novel therapeutic vaccines against hypnozoites or preventive vaccines with effect against multiple stages could have enormous impact. A target product profile (TPP) for VIMT is proposed and a research agenda to address current knowledge gaps and develop tools necessary for design and development of VIMT is presented.
Citation: The malERA Consultative Group on Vaccines (2011) A Research Agenda for Malaria Eradication: Vaccines. PLoS Med 8(1): e1000398. doi:10.1371/journal.pmed.1000398
Published: January 25, 2011
Funding: malERA received a grant from the Bill & Melinda Gates Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Competing interests: No competing interests: PLA, CC, VM, AS, DW. GB is the Chair of MALVAC, Chair of the USAID Malaria Vaccine Development Program Scientific Consultants Group, a member of the Board of Roll Back Malaria, and the APMEN Advisory Board. RB is an employee of Glaxo SmithKline (GSK) and owns GSK stock. GSK is developing malaria vaccines. At the time of the malERA meetings, RB was employed by the Bill & Melinda Gates Foundation. CL states that the PATH Malaria Vaccine Initiative has partnerships with several commercial entities developing malaria vaccines. Each partnership has defined access conditions.
Abbreviations: TBV, transmission-blocking vaccine; TPP, target product profile; VIMT, vaccines that interrupt malaria transmission
Copyright: © 2011 The malERA Consultative Group on Vaccines. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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