Introduction to Epidemiology 6th Edition by Ray M Merrill

Exercise 8

From the epidemic curve created in study question 1, what have you learned from this case thus far? Discuss the implications and observations of all time aspects of this disease. Discuss seasonal variation, cyclic trends, implication for duration of the disease, and incubation periods.

Question 1

Using the data below and a computer spreadsheet, create an epidemic curve bar graph.

Person/Disease: Cases of poliomyelitis recorded in Sweden

Place: Sweden

Time:Monthly reporting for the years of 1905, 1906, 1907; fromJanuary 1905 through

July 1907

Frequency: For the y-axis of the graph: 50-case increments up to 400 cases

1905 Cases	1906 Cases	1907 Cases
Jan. = 1	Jan. = 48	Jan. = 9
Feb. = 5	Feb. = 33	Feb. = 9
Mar. = 4	Mar. = 36	Mar. = 11
Apr. = 4	Apr. = 24	Apr. = 6
May = 8	May = 41	May = 5
Jun. = 20	Jun. = 15	Jun. = 13
Jul. = 138	Jul. = 21	Jul. = 51
Aug. = 367	Aug. = 32
Sept. = 242	Sept. = 49
Oct. = 140	Oct. = 22
Nov. = 69	Nov. = 31
Dec. = 38	Dec. = 24

Step 1 of 2

An epidemic curve is a representation of the number of cases (diseased individuals) observed during an outbreak or epidemic against time. This curve displays the course of the epidemic starting from the date or time of the epidemic onset. The form of the bar graph helps in the formulation of a hypothesis that describes the nature of the disease and the mode of transmission.