You can vaccinate against some bacteria, but I’ve never heard of a vaccine for a protist although there are ongoing attempts. This rundown is pretty thorough as

You can vaccinate against some bacteria, but I’ve never heard of a vaccine for a protist although there are ongoing attempts. This rundown is pretty thorough as to why it’s chalenging, and why that challenge is related to the complexity of something like Plasmodium compared to a simple organism like a bacteria or virus. https://www.nap.edu/read/9027/chapter/6 https://www.nap.edu/read/9027/chapter/6 The malaria parasite has multiple, immunologically distinct developmental stages and effective immune avoidance strategies. Single-antigen and single-stage vaccines have proved disappointing. Multi-antigen, multistage vaccines, which elicit different kinds of immune responses directed toward different antigens, appear more promising. High antibody levels can be effective against sporozoites and blood-stage parasites, but a cytotoxic cell response is needed to attack the critical liver stage, and antibodies are clearly needed to block transmission. Selecting the optimal antigens from among the stages in the parasite's life cycle and devising optimal formulations and delivery systems to elicit the desired immunologic response is a complex and difficult task, one that must be based on scientific knowledge, but will also require empirical testing of multiple potential vaccine products. Remember that a vaccine needs to produce an immune response that doesn’t lead to cytokine storm or devestating autoimmune response.