MODEL RELEASED. Typhoid vaccination. Female doctor injecting a male patient's buttock with a typhoid vaccine. Vaccines are killed or weakened disease- causing micro-organisms that prompt an immune response, which prepares the body for future infections. Typhoid is an infectious disease that can be contracted by eating food or drinking water that is contaminated with the Samonella typhi bacterium. Symptoms include a rash of red spots, fever and severe intestinal irritation. Epidemics occur regularly in developing countries, and unless treated will result in coma and death. Treatment includes both rehydrating fluids and antibiotics.