Immune response and imperfect vaccine in malaria dynamics

The immune response to malaria and the effects of an imperfect vaccine for this disease are modelled incorporating an n stage parasite life cycle, immune cells, and antibodies. A globally asymptotically stable parasite-free equilibrium occurs when the associated reproduction number is less than unity. An imperfect malaria vaccine that reduces the number of merozoites released per bursting infected red blood cell (IRBC) and that boosts immune response can reduce the concentration of IRBCs in vivo. Numerical simulations show that a vaccine efficacy of at least 87% is necessary to eliminate IRBC in vivo. The concentration of IRBCs varies with the capacity of the vaccine to modify the total number of merozoites released per bursting IRBC.