Immunological Impediments to Developing a Blood Stage Malaria Vaccine

There are 300-500 million cases of malaria each year and of the more than one million people that die each year from malaria, most are children under 5 years of age. The cloning of malaria antigens in 1983 offered great hope of developing a viable subunit vaccine. While some subunit vaccines have shown great promise in model systems, an efficacious human vaccine is still not available. Immunological studies have shown that numerous factors such as parasite's antigenic variation and polymorphism, immunological non-responsiveness to individual vaccine antigens, parasite-induced apoptosis of immune effector and memory cells, immune deviation as a result of maternal immunity and alterations of dendritic cell function can impede the development of vaccines. These findings indicate that alternative novel approaches are required to tackle the disease and induce protection against malaria.