Stem-and-Leaf plot is a method of organizing numerical data in order of place value. The 'ones digit' and the 'tens digit and greater' of each data item is separated as leaves and stems respectively. The stem-and-leaf plot below shows the number of students enrolled in a dance class in the past 12 years.
Vaccination with live viruses may interfere with TST reactions. For persons scheduled to receive a TST, testing should be done as follows: Either on the same day as vaccination with live-virus vaccine or 4-6 weeks after the administration of the live-virus vaccine. At least one month after smallpox vaccination.
On average, the time between coming in contact with the smallpox virus and developing symptoms (the incubation period) is 12 days. The incubation period ranges from 7 to 17 days. The first symptoms of smallpox are high fever, fatigue, headaches, and backaches. A rash that appears mostly on the face, arms, and legs starts about 2 to 3 days later. The rash starts out as a flat, spotty (papular) rash, but soon develops small vesicles (clear fluid-filled lesions) and then later the lesions become pustular (filled with cloudy white pus).