Ionizing radiation. Ingenious approach, sort of a pseudo-vaccine, kills and breaks apart a pathogen in the blood that was taken and when re-injected it presents

Ionizing radiation. Ingenious approach, sort of a pseudo-vaccine, kills and breaks apart a pathogen in the blood that was taken and when re-injected it presents a greater attack surface for the immune system to learn about the pathogen. Also whatever active measures the pathogen cells in the sample were taking to evade attention are no longer in effect since it's dead.