Can some one please check this for me. I am not sure if I am on the right track.

Question

Complete the problem below.

Disease X is one that often results in severe illness, but never is fatal. On March 21, 1990, 30 students developed disease X among all students in an introductory epidemiology course at a university. (Assume all epidemiology students were exposed to the index case, the instructor.) Through antibody titers we were able to determine the following:
Using your knowledge of infectious disease epidemiology, quantify the pattern of disease X in this group, i.e., what are the infectivity, pathogenicity, and virulence of disease X?

a.# of exposed students not infected = 40
Not Infected
Number of ill students + # of students not infected = Total Attack rate
30 40 70 43%
b. # of exposed students with sub clinical infection = 10
Sub clinical infection
# of exposed students + # of students not exposed = Total Attack rate
30 10 40 75%

c. # of exposed students with mild symptoms = 10
Mild symptoms
# of exposed students + # of students not expose = Total Attack rate
10 40 50 20%

d. # of exposed students with moderate symptoms = 10
Moderate symptoms
# with moderate symptoms + # without moderate symptoms= Total Attack rate
10 40 50 20%

e. # of exposed students with severe symptoms = 10
Severe symptoms
# exposed with symptoms + # without severe symptoms = Total Attack rate
10 40 50 20%

Thanks

Answer 1

The answer is