Targett Geoffrey A, Greenwood Brian M
Department of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK.
Malar J. 2008 Dec 11;7 Suppl 1(Suppl 1):S10. doi: 10.1186/1475-2875-7-S1-S10.
Research on malaria vaccines is currently directed primarily towards the development of vaccines that prevent clinical malaria. Malaria elimination, now being considered seriously in some epidemiological situations, requires a different vaccine strategy, since success will depend on killing all parasites in the community in order to stop transmission completely. The feature of the life-cycles of human malarias that presents the greatest challenge to an elimination programme is the persistence of parasites as asymptomatic infections. These are an important source from which transmission to mosquitoes can occur. Consequently, an elimination strategy requires a community-based approach covering all individuals and not just those who are susceptible to clinical malaria. The progress that has been made in development of candidate malaria vaccines is reviewed. It is unlikely that many of these will have the efficacy required for complete elimination of parasites, though they may have an important role to play as part of future integrated control programmes. Vaccines for elimination must have a high level of efficacy in order to stop transmission to mosquitoes. This might be achieved with some pre-erythrocytic stage candidate vaccines or by targeting the sexual stages directly with transmission-blocking vaccines. An expanded malaria vaccine programme with such objectives is now a priority.
疟疾疫苗的研究目前主要致力于开发预防临床疟疾的疫苗。在一些流行病学情况下,疟疾消除工作正受到认真考虑,这需要一种不同的疫苗策略,因为成功将取决于消灭社区内所有寄生虫,以便完全阻止传播。人类疟疾生命周期的特征给消除计划带来最大挑战的是寄生虫以无症状感染形式持续存在。这些是可发生向蚊子传播的重要源头。因此,消除策略需要一种基于社区的方法,涵盖所有个体,而不仅仅是那些易患临床疟疾的个体。本文综述了候选疟疾疫苗开发所取得的进展。这些疫苗中许多不太可能具备完全消除寄生虫所需的效力,不过它们作为未来综合防治计划的一部分可能发挥重要作用。用于消除疟疾的疫苗必须具备高效力,以阻止向蚊子传播。这或许可通过一些处于红细胞前期的候选疫苗来实现,或者通过用传播阻断疫苗直接针对有性阶段来实现。现在,以这些目标为导向扩大疟疾疫苗计划是当务之急。