Patent ID: 6890527

Claim:
A method of improving the safety of a live protozoa vaccine that produces protective immunity against a protozoal disease in a subject, said method comprising: administering to the subject a vaccine conjugate comprising a live pathogenic protozoa and a neutralizing factor bound to the live protozoa, the neutralizing factor selected from the group consisting of neutralizing antibodies and neutralizing antibody fragments which are capable of neutralizing the live protozoa; wherein the neutralizing factor is provided in the vaccine conjugate in an amount that temporarily neutralizes the live protozoa, so that the pathogenic effects of the live protozoa in the vaccine are delayed due to the addition of the neutralizing factor as compared with the pathogenic effects of the live protozoa in the absence of the neutralizing factor, and the live protozoa retains the ability to replicate and infect the subject and induce a protective immune response against a later challenge with the live protozoa in the subject.