Cholera, a serious intestinal disease, broke out in London in the mid-19th century. People at that time believed cholera was caused by bad air. A physician named John Snow discovered that 61 victims either used the water pump on Broad Street or lived nearby. His research became the basis for the theory that germs cause disease. In the case of cholera, the germs are transmitted by polluted water. A vaccine for cholera was developed in the late 1800s. A vaccine is a drug that helps a person become immune to a disease. Scientists studied 818 people to determine the effects of a cholera vaccine. The study lasted from 1894 to 1896. Infected Not Infected Vaccinated 3 276 Not vaccinated 66 473 Use the information in the table to complete the following four statements. Round to the nearest tenth of a percent. Incorrect% of those vaccinated were infected % of those not vaccinated were infected % of those infected were vaccinated % of those infected were not vaccinated