Principios de las pruebas de vacunas contra la malaria: Memorandum de una reunion de la OMS

Abstract

Despite the considerable advances recently achieved in malaria control, the disease has remained a major public health problem in many tropical and sub-tropical countries. The development of vaccines against malaria has progressed rapidly over the past few years, and it is expected that they will play an important role in controlling the disease in the not-too-distant future. This Memorandum presents the strategies recommended by the World Health Organization for the performance of malaria vaccine trials. Malaria vaccines will be based on pure parasite antigens which specifically stimulate protective immune responses. In view of the life cycle of the Plasmodium, the three types of vaccine now being developed target sporozoites, asexual erythrocytic stages, and gametes. Each vaccine would confer specific immunity and its application would thus be directed at different population groups according to their epidemiological situation. A sporozoite vaccine, if fully effective, would prevent plasmodial development in the host. A vaccine of this type should be able to interrupt the natural transmission of malaria, although a given subject would show clinical illness if transfused with infected blood since he/she would not be immune to the asexual erythrocytic forms. An asexual erythrocytic-stage vaccine would restrict the replication of these forms, but would not induce sterile immunity