The hospital was a large, two-story building, but Dr. Welch decided not to admit the diphtheria patients. He kept them isolated in their homes and treated them there one at a time. This would help contain the disease. But the only really effective way to stop an epidemic from spreading through the entire town was to vaccinate people against it. The doctor had a small amount of vaccine, or serum, but it was five years old - possibly useless - and would not go far. He must find more. —Susan Butcher and the Iditarod Trail, Ellen M. Dolan Here is a prediction: Curtis Welch will become infected with Black Death. Use the drop-down menus to answer the questions. Is this prediction correct? What should you do now? What is a logical new prediction? How do you verify your prediction?